107 results on '"Christina Andreou"'
Search Results
2. Chaos analysis of the cortical boundary for the recognition of psychosis
- Author
-
Alexandra I. Korda, Christina Andreou, Mihai Avram, Marina Frisman, Mariya Aliqadri, Anita Riecher-Rössler, Heinz Handels, Thomas Martinetz, and Stefan Borgwardt
- Subjects
Psychiatry and Mental health ,Pharmacology (medical) ,Biological Psychiatry - Published
- 2023
3. Brain texture as a marker of transdiagnostic clinical profiles in patients with recent-onset psychosis and depression
- Author
-
Alexandra Korda, Christina Andreou, Anne Ruef, Lisa Hahn, André Schmidt, Udo Dannlowski, Lana Kambeitz-Ilankovic, Dominic Dwyer, Joseph Kambeitz, Julian Wenzel, Stephan Ruhrmann, Raimo Salokangas, Christos Pantelis, Frauke Schultze-Lutter, Eva Meisenzahl, Paolo Brambilla, Pierluigi Selvaggi, Rachel Upthegrove, Paris Alexandros Lalousis, Anita Riecher-Rössler, Christos Davatzikos, Rebekka Lencer, Nikolaos Koutsouleris, and Stefan Borgwardt
- Abstract
Prediction models of brain texture changes in recent-onset psychosis (ROP) and recent-onset depression (ROD) have lately been proposed. The validation of these models transdiagnostically at the individual level and the investigation of the variability in clinical profiles are still missing. Established prevention and treatment approaches focus on specific diagnoses and do not address the heterogeneity and manifold potential outcomes of patients. We aimed to investigate the utility of brain texture changes for a) identification of the psychopathological state (ROP and ROD) and b) the association of individualized brain texture maps with clinical symptom severity and outcome profiles. We developed transdiagnostic models based on structural MRI data on 116 patients with ROD, 122 patients with ROP, and 197 healthy controls (HC) from the Personalised pROgNostic tools for early psychosIs mAnagement (PRONIA) study by applying explainable artificial intelligence and clustering analysis. We investigated the contrast texture feature as the key feature for the identification of a general psychopathological state. The discrimination power of the trained prediction model was > 72% and validated in a second independent age and sex-matched sample of 137 ROP, 94 ROD, and 159 HC. Clustering analysis was implemented to map the texture brain changes produced from an explainable artificial intelligence algorithm, in a group fashion. The explained individualized brain contrast map grouped into 8 homogeneous clusters. In each group, we investigated the association between the explained brain contrast texture map and clinical symptom severity as well as outcome profiles. Different patterns in the explained brain contrast texture map showed unique associations of brain alterations with clinical symptom severity and clinical outcomes, i.e., age, positive, negative and depressive symptoms, and functionality. In some clusters, the mean explained brain contrast texture map values and/or brain contrast texture voxels significantly contribute to the classification decision significantly predicted PANSS scores, functionality and change in functionality over time. In conclusion, we created homogeneous clusters which statistically significant predict the clinical severity and outcome profile.
- Published
- 2023
4. Aberrant perception of environmental volatility during social learning in emerging psychosis
- Author
-
Daniel J. Hauke, Michelle Wobmann, Christina Andreou, Amatya Mackintosh, Renate de Bock, Povilas Karvelis, Rick A. Adams, Philipp Sterzer, Stefan Borgwardt, Volker Roth, and Andreea O. Diaconescu
- Abstract
Paranoid delusions or unfounded beliefs that others intend to deliberately cause harm are a frequent and burdensome symptom in early psychosis, but their emergence and consolidation still remains opaque. Recent theories suggest that aberrant prediction errors lead to a brittle model of the world providing a breeding ground for delusions. Here, we employ a Bayesian approach to test for a more unstable model of the world and investigate the computational mechanisms underlying emerging paranoia.We modelled behaviour of 18 first-episode psychosis patients (FEP), 19 individuals at clinical high-risk for psychosis (CHR-P), and 19 healthy controls (HC) during an advice-taking task, designed to probe learning about others’ changing intentions. We formulated competing hypotheses comparing the standard Hierarchical Gaussian Filter (HGF), a Bayesian belief updating scheme, with a mean-reverting HGF to model an altered perception of volatility.There was a significant group-by-volatility interaction on advice-taking suggesting that CHR-P and FEP displayed reduced adaptability to environmental volatility. Model comparison favored the standard HGF in HC, but the mean-reverting HGF in CHR-P and FEP in line with perceiving increased volatility, although model attributions in CHR-P were heterogeneous. We observed correlations between shifts in perceived volatility and positive symptoms generally as well as with frequency of paranoid delusions specifically.Our results suggest that FEP are characterised by a different computational mechanism – perceiving the environment as increasingly volatile – in line with Bayesian accounts of psychosis. This approach may prove useful to investigate heterogeneity in CHR-P and identify vulnerability for transition to psychosis.
- Published
- 2023
5. Nonlinear Methods for the Investigation of Psychotic Disorders
- Author
-
Alexandra Korda, Marina Frisman, Christina Andreou, and Stefan Borgwardt
- Published
- 2023
6. Circadian Rhythms in Auditory Hallucinations and Psychosis
- Author
-
Hong‐Viet V. Ngo, Henrik Oster, Christina Andreou, and Jonas Obleser
- Subjects
Physiology - Abstract
Circadian rhythms are imprinted in all organisms and influence virtually all aspects of physiology and behaviour in adaptation to the 24-hour day-night cycle. This recognition of a circadian timekeeping system permeating essentially all healthy functioning of body and mind quickly leads to the realisation that, in turn, human ailments should be probed for the degree to which they are rooted in or marked by disruptions and dysregulations of circadian clock functions in the human body. In this review, we will focus on psychosis as a key mental illness and foremost one of its cardinal symptoms: auditory hallucinations. We will discuss recent empirical evidence and conceptual advances probing the potential role of circadian disruption in auditory hallucinations. Moreover, a dysbalance in excitation and inhibition within cortical networks, which in turn drive a disinhibition of dopaminergic signalling will be highlighted as central physiological mechanism. Finally, we will propose two avenues for experimentally intervening on the circadian influences to potentially alleviate hallucinations in psychotic disorders.
- Published
- 2022
7. P300 and delay-discounting in obsessive–compulsive disorder
- Author
-
Björn Enzi, Christina Andreou, Georg Juckel, Vera Flasbeck, and Paraskevi Mavrogiorgou
- Subjects
Obsessive-Compulsive Disorder ,medicine.medical_specialty ,Brain activity and meditation ,Posterior parietal cortex ,Context (language use) ,Audiology ,behavioral disciplines and activities ,Temporal lobe ,03 medical and health sciences ,0302 clinical medicine ,Neuroimaging ,Event-related potential ,mental disorders ,medicine ,Humans ,Pharmacology (medical) ,Association (psychology) ,Biological Psychiatry ,Cognition ,General Medicine ,Event-Related Potentials, P300 ,Magnetic Resonance Imaging ,030227 psychiatry ,Psychiatry and Mental health ,Delay Discounting ,Psychology ,030217 neurology & neurosurgery - Abstract
Previous research showed that dysfunctions of fronto-striatal neural networks are implicated in the pathophysiology of obsessive–compulsive disorder (OCD). Accordingly, patients with OCD showed altered performances during decision-making tasks. As P300, evoked by oddball paradigms, is suggested to be related to attentional and cognitive processes and generated in the medial temporal lobe and orbitofrontal and cingulate cortices, it is of special interest in OCD research. Therefore, this study aimed to investigate P300 in OCD and its associations with brain activity during decision-making: P300, evoked by an auditory oddball paradigm, was analysed in 19 OCD patients and 19 healthy controls regarding peak latency, amplitude and source density power in parietal cortex areas by sLORETA. Afterwards, using a fMRI paradigm, Blood–oxygen-level-dependent (BOLD) contrast imaging was conducted during a delay-discounting paradigm. We hypothesised differences between groups regarding P300 characteristics and associations with frontal activity during delay-discounting. The P300 did not differ between groups, however, the P300 latency over the P4 electrode correlated negatively with the NEO-FFI score openness to experience in patients with OCD. In healthy controls, P300 source density power correlated with activity in frontal regions when processing rewards, a finding which was absent in OCD patients. To conclude, associations of P300 with frontal brain activation during delay-discounting were found, suggesting a contribution of attentional or context updating processes. Since this association was absent in patients with OCD, the findings could be interpreted as being indeed related to dysfunctions of fronto-striatal neural networks in patients with OCD.
- Published
- 2021
8. Chaos analysis of the brain topology in first-episode psychosis and clinical high risk patients
- Author
-
Alexandra I. Korda, Christina Andreou, Mihai Avram, Heinz Handels, Thomas Martinetz, and Stefan Borgwardt
- Subjects
Psychiatry and Mental health - Abstract
Structural MRI studies in first-episode psychosis (FEP) and in clinical high risk (CHR) patients have consistently shown volumetric abnormalities in frontal, temporal, and cingulate cortex areas. The aim of the present study was to employ chaos analysis for the identification of brain topology differences in people with psychosis. Structural MRI were acquired from 77 FEP, 73 CHR and 44 healthy controls (HC). Chaos analysis of the gray matter distribution was performed: First, the distances of each voxel from the center of mass in the gray matter image was calculated. Next, the distances multiplied by the voxel intensity were represented as a spatial-series, which then was analyzed by extracting the Largest-Lyapunov-Exponent (lambda). The lambda brain map depicts thus how the gray matter topology changes. Between-group differences were identified by (a) comparing the lambda brain maps, which resulted in statistically significant differences in FEP and CHR compared to HC; and (b) matching the lambda series with the Morlet wavelet, which resulted in statistically significant differences in the scalograms of FEP against CHR and HC. The proposed framework using spatial-series extraction enhances the between-group differences of FEP, CHR and HC subjects, verifies diagnosis-relevant features and may potentially contribute to the identification of structural biomarkers for psychosis.
- Published
- 2022
9. PsyYoung : un projet pluri-cantonal pour faciliter l’accès aux soins des jeunes à risque de développer une psychose
- Author
-
Christina Andreou, Barbara Bailey, Marco Armando, Nadia Micali, Christian Huber, Evelyn Herbrecht, Logos Curtis, Davina Genoud, Stefan Borgwardt, Kerstin Jessica Plessen, Philippe Conus, and Alessandra Solida
- Subjects
General Medicine - Published
- 2021
10. Traces of Trauma: A Multivariate Pattern Analysis of Childhood Trauma, Brain Structure, and Clinical Phenotypes
- Author
-
David Popovic, Anne Ruef, Dominic B. Dwyer, Linda A. Antonucci, Julia Eder, Rachele Sanfelici, Lana Kambeitz-Ilankovic, Omer Faruk Oztuerk, Mark S. Dong, Riya Paul, Marco Paolini, Dennis Hedderich, Theresa Haidl, Joseph Kambeitz, Stephan Ruhrmann, Katharine Chisholm, Frauke Schultze-Lutter, Peter Falkai, Giulio Pergola, Giuseppe Blasi, Alessandro Bertolino, Rebekka Lencer, Udo Dannlowski, Rachel Upthegrove, Raimo K.R. Salokangas, Christos Pantelis, Eva Meisenzahl, Stephen J. Wood, Paolo Brambilla, Stefan Borgwardt, Nikolaos Koutsouleris, Mark Sen Dong, Anne Erkens, Eva Gussmann, Shalaila Haas, Alkomiet Hasan, Claudius Hoff, Ifrah Khanyaree, Aylin Melo, Susanna Muckenhuber-Sternbauer, Janis Köhler, Ömer Faruk Öztürk, Nora Penzel, Adrian Rangnick, Sebastian von Saldern, Moritz Spangemacher, Ana Tupac, Maria Fernanda Urquijo, Johanna Weiske, Julian Wenzel, Antonia Wosgien, Linda Betz, Karsten Blume, Mauro Seves, Nathalie Kaiser, Thorsten Lichtenstein, Christiane Woopen, Christina Andreou, Laura Egloff, Fabienne Harrisberger, Claudia Lenz, Letizia Leanza, Amatya Mackintosh, Renata Smieskova, Erich Studerus, Anna Walter, Sonja Widmayer, Chris Day, Sian Lowri Griffiths, Mariam Iqbal, Mirabel Pelton, Pavan Mallikarjun, Alexandra Stainton, Ashleigh Lin, Alexander Denissoff, Anu Ellilä, Tiina From, Markus Heinimaa, Tuula Ilonen, Päivi Jalo, Heikki Laurikainen, Maarit Lehtinen, Antti Luutonen, Akseli Mäkela, Janina Paju, Henri Pesonen, Reetta-Liina Armio (Säilä, Elina Sormunen, Anna Toivonen, Otto Turtonen, Ana Beatriz Solana, Manuela Abraham, Nicolas Hehn, Timo Schirmer, Carlo Altamura, Marika Belleri, Francesca Bottinelli, Adele Ferro, Marta Re, Emiliano Monzani, Mauro Percudani, Maurizio Sberna, Armando D’Agostino, Lorenzo Del Fabro, Giampaolo Perna, Maria Nobile, Alessandra Alciati, Matteo Balestrieri, Carolina Bonivento, Giuseppe Cabras, Franco Fabbro, Marco Garzitto, and Sara Piccin
- Subjects
Male ,0301 basic medicine ,Psychosis ,media_common.quotation_subject ,03 medical and health sciences ,0302 clinical medicine ,Brain Injuries, Traumatic ,Humans ,Medicine ,Personality ,Generalizability theory ,Gray Matter ,Child ,Biological Psychiatry ,media_common ,business.industry ,Brain morphometry ,Brain ,Cognition ,medicine.disease ,Phenotype ,030104 developmental biology ,Sexual abuse ,Cohort ,Quality of Life ,Trait ,Female ,business ,030217 neurology & neurosurgery ,Clinical psychology - Abstract
Background Childhood trauma (CT) is a major yet elusive psychiatric risk factor, whose multidimensional conceptualization and heterogeneous effects on brain morphology might demand advanced mathematical modeling. Therefore, we present an unsupervised machine learning approach to characterize the clinical and neuroanatomical complexity of CT in a larger, transdiagnostic context. Methods We used a multicenter European cohort of 1076 female and male individuals (discovery: n = 649; replication: n = 427) comprising young, minimally medicated patients with clinical high-risk states for psychosis; patients with recent-onset depression or psychosis; and healthy volunteers. We employed multivariate sparse partial least squares analysis to detect parsimonious associations between combinations of items from the Childhood Trauma Questionnaire and gray matter volume and tested their generalizability via nested cross-validation as well as via external validation. We investigated the associations of these CT signatures with state (functioning, depressivity, quality of life), trait (personality), and sociodemographic levels. Results We discovered signatures of age-dependent sexual abuse and sex-dependent physical and sexual abuse, as well as emotional trauma, which projected onto gray matter volume patterns in prefronto-cerebellar, limbic, and sensory networks. These signatures were associated with predominantly impaired clinical state- and trait-level phenotypes, while pointing toward an interaction between sexual abuse, age, urbanicity, and education. We validated the clinical profiles for all three CT signatures in the replication sample. Conclusions Our results suggest distinct multilayered associations between partially age- and sex-dependent patterns of CT, distributed neuroanatomical networks, and clinical profiles. Hence, our study highlights how machine learning approaches can shape future, more fine-grained CT research.
- Published
- 2020
11. Identification of texture MRI brain abnormalities on first-episode psychosis and clinical high-risk patients using explainable artificial intelligence
- Author
-
Alexandra Korda, Christina Andreou, Helena Victoria Rogg, Mihai Avram, Anne Ruef, Christos Davatzikos, Nikolaos Koutsouleris, and Stefan Borgwardt
- Abstract
Structural MRI studies in first-episode psychosis and the clinical high-risk state have consistently shown volumetric abnormalities. Aim of the present study was to introduce radiomics texture features in identification of psychosis. Radiomics texture features describe the interrelationship between voxel intensities across multiple spatial scales capturing the hidden information of underlying disease dynamics in addition to volumetric changes. Structural MR images were acquired from 77 first-episode psychosis (FEP) patients, 58 clinical high-risk patients with no later transition to psychosis (CHR_NT), 15 clinical high-risk patients with later transition (CHR_T) and 44 healthy controls (HC). Radiomics texture features were extracted from non-segmented images, and two classification schemas were performed for the identification of FEP vs. HC and FEP vs. CHR_NT. The group of CHR_T was used as external validation in both schemas. The classification of a subject’s clinical status was predicted by importing separately a) the difference of entropy feature map and b) the contrast feature map, resulting in classification accuracy above 72% in both analyses. The proposed framework enhances the classification decision for FEP, CHR_NT and HC subjects, verifies diagnosis-relevant features and may potentially contribute to identification of structural biomarkers for psychosis, beyond and above volumetric brain changes.
- Published
- 2022
12. Characterizing Thalamocortical (Dys)connectivity Following D-Amphetamine, LSD, and MDMA Administration
- Author
-
Mihai Avram, Felix Müller, Helena Rogg, Alexandra Korda, Christina Andreou, Friederike Holze, Patrick Vizeli, Laura Ley, Matthias E. Liechti, and Stefan Borgwardt
- Subjects
Lysergic Acid Diethylamide ,Cross-Over Studies ,Dextroamphetamine ,Lysergic Acid ,Double-Blind Method ,Cognitive Neuroscience ,N-Methyl-3,4-methylenedioxyamphetamine ,Hallucinogens ,Humans ,Radiology, Nuclear Medicine and imaging ,Neurology (clinical) ,Biological Psychiatry - Abstract
Patients with psychotic disorders present alterations in thalamocortical intrinsic functional connectivity as measured by resting-state functional magnetic resonance imaging. Specifically, thalamic intrinsic functional connectivity is increased with sensorimotor cortices (hyperconnectivity) and decreased with prefrontal limbic cortices (hypoconnectivity). Psychedelics such as lysergic acid diethlyamide (LSD) elicit similar thalamocortical hyperconnectivity with sensorimotor areas in healthy volunteers. It is unclear whether LSD also induces thalamocortical hypoconnectivity with prefrontal limbic cortices, because current findings are equivocal. Thalamocortical hyperconnectivity was associated with psychotic symptoms in patients and substance-induced altered states of consciousness in healthy volunteers. Thalamocortical dysconnectivity is likely evoked by altered neurotransmission, e.g., via dopaminergic excess in psychotic disorders and serotonergic agonism in psychedelic-induced states. It is unclear whether thalamocortical dysconnectivity is also elicited by amphetamine-type substances, broadly releasing monoamines (i.e., dopamine, norepinephrine) but producing fewer perceptual effects than psychedelics.We administrated LSD, d-amphetamine, and 3,4-methylenedioxymethamphetamine (MDMA) in 28 healthy volunteers and investigated their effects on thalamic intrinsic functional connectivity with 2 brain networks (auditory-sensorimotor and salience networks, corresponding to sensorimotor and prefrontal limbic cortices, respectively), using a double-blind, placebo-controlled, crossover design.All active substances elicited auditory-sensorimotor-thalamic hyperconnectivity compared with placebo, despite predominantly distinct pharmacological actions and subjective effects. LSD-induced effects correlated with subjective changes in perception, indicating a link between hyperconnectivity and psychedelic-type perceptual alterations. Unlike d-amphetamine and MDMA, which induced hypoconnectivity with the salience network, LSD elicited hyperconnectivity. D-amphetamine and MDMA evoked similar thalamocortical dysconnectivity patterns.Psychedelics, empathogens, and psychostimulants evoke thalamocortical hyperconnectivity with sensorimotor areas, akin to findings in patients with psychotic disorders.
- Published
- 2022
13. Neurobiologically Based Stratification of Recent-Onset Depression and Psychosis: Identification of Two Distinct Transdiagnostic Phenotypes
- Author
-
Paris Alexandros Lalousis, Lianne Schmaal, Stephen J. Wood, Renate L.E.P. Reniers, Nicholas M. Barnes, Katharine Chisholm, Sian Lowri Griffiths, Alexandra Stainton, Junhao Wen, Gyujoon Hwang, Christos Davatzikos, Julian Wenzel, Lana Kambeitz-Ilankovic, Christina Andreou, Carolina Bonivento, Udo Dannlowski, Adele Ferro, Theresa Lichtenstein, Anita Riecher-Rössler, Georg Romer, Marlene Rosen, Alessandro Bertolino, Stefan Borgwardt, Paolo Brambilla, Joseph Kambeitz, Rebekka Lencer, Christos Pantelis, Stephan Ruhrmann, Raimo K.R. Salokangas, Frauke Schultze-Lutter, André Schmidt, Eva Meisenzahl, Nikolaos Koutsouleris, Dominic Dwyer, and Rachel Upthegrove
- Subjects
Phenotype ,Psychotic Disorders ,Depression ,Humans ,Neuroimaging ,Gray Matter ,Biological Psychiatry - Abstract
BACKGROUND Identifying neurobiologically based transdiagnostic categories of depression and psychosis may elucidate heterogeneity and provide better candidates for predictive modeling. We aimed to identify clusters across patients with recent-onset depression (ROD) and recent-onset psychosis (ROP) based on structural neuroimaging data. We hypothesized that these transdiagnostic clusters would identify patients with poor outcome and allow more accurate prediction of symptomatic remission than traditional diagnostic structures. METHODS HYDRA (Heterogeneity through Discriminant Analysis) was trained on whole-brain volumetric measures from 577 participants from the discovery sample of the multisite PRONIA study to identify neurobiologically driven clusters, which were then externally validated in the PRONIA replication sample (n = 404) and three datasets of chronic samples (Centre for Biomedical Research Excellence, n = 146; Mind Clinical Imaging Consortium, n = 202; Munich, n = 470). RESULTS The optimal clustering solution was two transdiagnostic clusters (cluster 1: n = 153, 67 ROP, 86 ROD; cluster 2: n = 149, 88 ROP, 61 ROD; adjusted Rand index = 0.618). The two clusters contained both patients with ROP and patients with ROD. One cluster had widespread gray matter volume deficits and more positive, negative, and functional deficits (impaired cluster), and one cluster revealed a more preserved neuroanatomical signature and more core depressive symptomatology (preserved cluster). The clustering solution was internally and externally validated and assessed for clinical utility in predicting 9-month symptomatic remission, outperforming traditional diagnostic structures. CONCLUSIONS We identified two transdiagnostic neuroanatomically informed clusters that are clinically and biologically distinct, challenging current diagnostic boundaries in recent-onset mental health disorders. These results may aid understanding of the etiology of poor outcome patients transdiagnostically and improve development of stratified treatments.
- Published
- 2022
- Full Text
- View/download PDF
14. Multiparameter Single-Cell Characterization of Ovarian Intratumor Heterogeneity
- Author
-
Kristin G, Beaumont, Christina, Andreou, Ethan, Ellis, and Robert, Sebra
- Subjects
Ovarian Neoplasms ,Tumor Microenvironment ,High-Throughput Nucleotide Sequencing ,Humans ,Female ,Single-Cell Analysis - Abstract
Cancer is a complex disease rooted in heterogeneity, which is the phenomenon of individual cells, tissues, or patients having distinct phenotypic and/or genetic characteristics. Observed divergent disease etiology is likely rooted, at least in part, in tumor heterogeneity and the classification of distinct and important subpopulations of cells within the tumor and its associated microenvironment has remained a technical challenge. Standard next-generation sequencing of bulk tumor tissue provides an overall average genetic profile of the sample, and masks contributions from individual cells and minor populations of cells, particularly in heterogeneous samples. Only with the advent of single-cell analysis and sequencing technologies has it become possible to characterize key contributions of cellular subpopulations in order to more comprehensively characterize disease. This chapter describes a method to generate linked phenotypic and genotypic data at single-cell resolution using a real-time single-cell resolved platform. Specifically, the example method provided here is used to link cellular growth kinetics and expression of a prognostic marker protein, CA-125, in cells derived from ovarian cancer patients with their single-cell genomic profiles, but the method is translatable to other cell types and phenotypes of interest.
- Published
- 2021
15. Chaos Analysis of the Brain Topology in Grey Matter Images for the Recognition of Psychosis
- Author
-
Alexandra I. Korda, Mihai Avram, Christina Andreou, Thomas Martinetz, and Stefan Borgwardt
- Abstract
Structural MRI studies in first-episode psychosis (FEP) and in clinical high risk (CHR) patients have consistently shown volumetric abnormalities in frontal, temporal, and cingulate cortex areas. The aim of the present study was to employ chaos analysis in the identification of people with psychosis. Structural MRI were acquired from 73 CHR, 77 FEP and 44 healthy controls (HC). Chaos analysis of the grey matter distribution was performed: first, the distances of each voxel from the center of mass in the grey matter image was calculated. Next, the distances multiplied by the voxel intensity was represented as a spatial-series, which then was analyzed by extracting the Largest-Lyapunov-Exponent (lambda). The lambda brain map depicts how the grey matter topology changes. The classification of a subject’s clinical status was finally predicted by a) comparing the lambda brain maps, which resulted in statistically significant differences in FEP and CHR compared to HC; and b) matching the lambda series with the Morlet wavelet, which resulted in 100% accuracy in distinguishing between FEP and CHR. The proposed framework using spatial-series extraction enhances the classification decision for FEP, CHR and HC subjects, verifies diagnosis-relevant features and may potentially contribute to the identification of structural biomarkers for psychosis.
- Published
- 2021
16. Multiparameter Single-Cell Characterization of Ovarian Intratumor Heterogeneity
- Author
-
Kristin G. Beaumont, Christina Andreou, Ethan Ellis, and Robert Sebra
- Published
- 2021
17. Bridging the Gap? Altered Thalamocortical Connectivity in Psychotic and Psychedelic States
- Author
-
Stefan Borgwardt, Mihai Avram, Alexandra Korda, Christina Andreou, Felix Müller, and Helena Rogg
- Subjects
Psychiatry ,Psychosis ,medicine.diagnostic_test ,Mini Review ,media_common.quotation_subject ,Thalamus ,RC435-571 ,Cognition ,Hyperconnectivity ,serotonergic psychedelics ,medicine.disease ,Reality testing ,Psychiatry and Mental health ,Perception ,cortico-thalamic connectivity ,resting-state FC-fMRI ,medicine ,psychedelic states ,Psychology ,Functional magnetic resonance imaging ,Neuroscience ,Neurocognitive ,psychotic states ,media_common - Abstract
Psychiatry has a well-established tradition of comparing drug-induced experiences to psychotic symptoms, based on shared phenomena such as altered perceptions. The present review focuses on experiences induced by classic psychedelics, which are substances capable of eliciting powerful psychoactive effects, characterized by distortions/alterations of several neurocognitive processes (e.g., hallucinations). Herein we refer to such experiences as psychedelic states. Psychosis is a clinical syndrome defined by impaired reality testing, also characterized by impaired neurocognitive processes (e.g., hallucinations and delusions). In this review we refer to acute phases of psychotic disorders as psychotic states. Neuropharmacological investigations have begun to characterize the neurobiological mechanisms underpinning the shared and distinct neurophysiological changes observed in psychedelic and psychotic states. Mounting evidence indicates changes in thalamic filtering, along with disturbances in cortico-striato-pallido-thalamo-cortical (CSPTC)-circuitry, in both altered states. Notably, alterations in thalamocortical functional connectivity were reported by functional magnetic resonance imaging (fMRI) studies. Thalamocortical dysconnectivity and its clinical relevance are well-characterized in psychotic states, particularly in schizophrenia research. Specifically, studies report hyperconnectivity between the thalamus and sensorimotor cortices and hypoconnectivity between the thalamus and prefrontal cortices, associated with patients' psychotic symptoms and cognitive disturbances, respectively. Intriguingly, studies also report hyperconnectivity between the thalamus and sensorimotor cortices in psychedelic states, correlating with altered visual and auditory perceptions. Taken together, the two altered states appear to share clinically and functionally relevant dysconnectivity patterns. In this review we discuss recent findings of thalamocortical dysconnectivity, its putative extension to CSPTC circuitry, along with its clinical implications and future directions.
- Published
- 2021
18. Clinical and functional long-term outcome of patients at clinical high risk (CHR) for psychosis without transition to psychosis: A systematic review
- Author
-
Letizia Leanza, Katharina Beck, Christina Andreou, Erich Studerus, Sarah Ittig, Ulrike Heitz, and Anita Riecher-Rössler
- Subjects
Pediatrics ,medicine.medical_specialty ,Psychosis ,business.industry ,medicine.disease ,Outcome (game theory) ,030227 psychiatry ,3. Good health ,03 medical and health sciences ,Psychiatry and Mental health ,0302 clinical medicine ,Psychotic Disorders ,Clinical diagnosis ,Outcome Assessment, Health Care ,Disease Progression ,medicine ,Humans ,Medical diagnosis ,business ,Psychosocial ,030217 neurology & neurosurgery ,Biological Psychiatry - Abstract
Background Research on patients at clinical high risk (CHR) for psychosis has so far mainly focused on those with transition to frank psychosis (CHR-T patients). However, the majority of CHR patients do not transition (CHR-NT patients) and relatively little information is available on their clinical and functional outcome. Methods We conducted a systematic review on clinical and functional long-term outcome of CHR-NT patients. Studies were included if they had an average follow-up period of at least 24 months and reported on long-term outcome of CHR-NT patients in one or more of the following domains: (non-)remission from CHR, prevalence of clinical symptoms and/or clinical diagnoses (axis I and II), and psychosocial functioning. Results Ten publications from seven different single or multicenter studies with average follow-up durations of 2–7.5 years could be included. At the last follow-up assessment 28–71% of CHR-NT patients were not remitted from their CHR and 22–82% still had at least one clinical diagnosis. Approximately half of CHR-NT patients presented with poor psychosocial outcome at 2-year and 6-year follow-up. Conclusions The results suggest that, in the long-term, the majority of CHR-NT patients are not in full clinical remission and seem to suffer from one or more clinical disorders and psychosocial impairments. Since relatively few studies could be identified, further research is required to better understand the trajectories and clinical needs of CHR-NT patients.
- Published
- 2019
19. Assessment and treatment of individuals at high risk for psychosis
- Author
-
Christina Andreou, Barbara Bailey, and Stefan Borgwardt
- Subjects
Psychosis ,medicine.medical_specialty ,business.industry ,Psychosis risk ,Early detection ,Treatment options ,Signs and symptoms ,At risk mental state ,medicine.disease ,Psychiatry and Mental health ,Schizophrenia ,Intervention (counseling) ,Medicine ,business ,Psychiatry - Abstract
SUMMARYEarly detection and specialised early intervention for people at high risk for psychotic disorders have received growing attention in the past few decades, with the aim of delaying or preventing the outbreak of explicit psychotic symptoms and improving functional outcomes. This article summarises criteria for a diagnosis of high psychosis risk, the implications for such a diagnosis and recommendations for treatment.LEARNING OBJECTIVESAfter reading this article you will be able to: •recognise signs and symptoms indicating increased psychosis risk•understand uses and limitations of screening for high psychosis risk, and interpretation of results•recognise evidence-based treatment options for patients at clinical high risk for psychosis.DECLARATION OF INTERESTC.A. has received non-financial support from Sunovion and Lundbeck in the past 36 months.
- Published
- 2019
20. Reduced auditory evoked gamma-band response and schizophrenia-like clinical symptoms under subanesthetic ketamine
- Author
-
Lars Eichler, Christoph Mulert, Gregor Leicht, Stephanie Thiebes, Christian Zöllner, Nenad Polomac, Jürgen Gallinat, Saskia Steinmann, Christina Andreou, Iris-Carola Eichler, and Stjepan Curic
- Subjects
Adult ,Male ,Glutamic Acid ,Neurophysiology ,Placebo ,Article ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Gamma Rhythm ,Humans ,Medicine ,Ketamine ,Anterior cingulate cortex ,Pharmacology ,Positive and Negative Syndrome Scale ,business.industry ,Glutamate receptor ,Brain ,medicine.disease ,Crossover study ,030227 psychiatry ,Psychiatry and Mental health ,medicine.anatomical_structure ,Acoustic Stimulation ,Schizophrenia ,Anesthesia ,Evoked Potentials, Auditory ,NMDA receptor ,business ,Excitatory Amino Acid Antagonists ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Abnormal gamma-band oscillations (GBO) have been frequently associated with the pathophysiology of schizophrenia. GBO are modulated by glutamate, a neurotransmitter, which is continuously discussed to shape the complex symptom spectrum in schizophrenia. The current study examined the effects of ketamine, a glutamate N-methyl-d-aspartate receptor (NMDAR) antagonist, on the auditory-evoked gamma-band response (aeGBR) and psychopathological outcomes in healthy volunteers to investigate neuronal mechanisms of psychotic behavior. In a placebo-controlled, randomized crossover design, the aeGBR power, phase-locking factor (PLF) during a choice reaction task, the Positive and Negative Syndrome Scale (PANSS) and the Altered State of Consciousness (5D-ASC) Rating Scale were assessed in 25 healthy subjects. Ketamine was applied in a subanaesthetic dose. Low-resolution brain electromagnetic tomography was used for EEG source localization. Significant reductions of the aeGBR power and PLF were identified under ketamine administration compared to placebo (p
- Published
- 2019
21. Single-Cell Characterization of Calcium Influx and HIV-1 Infection using a Multiparameter Optofluidic Platform
- Author
-
Kristin G. Beaumont, Christina Andreou, Tracey L. Freeman, Talia H. Swartz, and Robert Sebra
- Subjects
Cell signaling ,Cell type ,Optics and Photonics ,General Immunology and Microbiology ,General Chemical Engineering ,General Neuroscience ,Cell ,Optical Devices ,HIV Infections ,Biology ,Microfluidic Analytical Techniques ,Virus ,Article ,General Biochemistry, Genetics and Molecular Biology ,Cell biology ,Cell Line ,Chronic infection ,medicine.anatomical_structure ,Live cell imaging ,medicine ,Fluorescence microscope ,HIV-1 ,Humans ,Calcium ,Signal transduction - Abstract
HIV-1 causes a chronic infection that affects more than 37 million people worldwide. People living with human immunodeficiency virus (HIV) experience comorbidity related to chronic inflammation despite antiretroviral therapy. However, these inflammatory signaling has not been fully characterized. The role of early entry events on the activation of cellular signaling events and downstream gene expression has not been captured at the single-cell level. Here the authors describe a method that applies principles of live-cell fluorescence microscopy to an automated single-cell platform that cultures and images cells over user-customized time courses, allowing for high-throughput analysis of dynamic cellular processes. This assay can track single-cell live fluorescence microscopy of early events that immediately follow HIV-1 infection, notably the influx of calcium that accompanies exposure to the virus and the development of productive infection using a fluorescent reporter virus. MT-4 cells are loaded with a calcium-sensitive dye and cultured in isolated pens on a nanofluidic device. The cultured cells are infected with an HIV-1 reporter virus (HIV-1 NLCI). A fluorescence microscope positioned above the nanofluidic device measures calcium influx over an 8-min time course following acute HIV-1 exposure. HIV-1 productive infection is measured in those same cells over a 4-day interval. Imaging data from these time courses are analyzed to define virus-host receptor interactions and signaling pathway dynamics. The authors present an integrated, scalable alternative to traditional imaging methods using a novel optofluidic platform capable of single-cell sorting, culturing, imaging, and software automation. This assay can measure the kinetics of events under various conditions, including cell type, agonist, or antagonist effect, while measuring an array of parameters. This is the first established method for nanofluidic high-throughput longitudinal single-cell culture and imaging: This technique can be broadly adapted to study cellular signaling kinetics and dynamic molecular interactions.
- Published
- 2021
22. Multimodal Machine Learning Workflows for Prediction of Psychosis in Patients With Clinical High-Risk Syndromes and Recent-Onset Depression
- Author
-
David Popovic, Laura Egloff, Christina Andreou, Benno G. Schimmelmann, Stephen J. Wood, Georg Romer, Anita Riecher-Rössler, Maurizia Franscini, Carlo Maj, Christian Schmidt-Kraepelin, Shalaila S. Haas, André Schmidt, Paolo Brambilla, Jarmo Hietala, Johanna Weiske, Rahel Flückiger, Timo Schirmer, Peter Krawitz, Stephan Ruhrmann, Linda A. Antonucci, Susanne Neufang, Nora Penzel, Roman Buechler, Katharine Chisholm, Chantal Michel, Eva Meisenzahl, Petra Walger, Raimo K. R. Salokangas, Rachel Upthegrove, Anastasia Theodoridou, Anne Ruef, Theresa Haidl, Alessandro Bertolino, Nikolaos Koutsouleris, Peter Falkai, Karsten Heekeren, Christos Pantelis, Nina Traber-Walker, Dominic B. Dwyer, Rebekka Lencer, Markus M. Noethen, Oleg V. Borisov, Wulf Rössler, Stefan Borgwardt, Frauke Schultze-Lutter, Maria Fernanda Urquijo-Castro, Lana Kambeitz-Ilankovic, Franziska Degenhardt, Oemer Faruk Oeztuerk, Joseph Kambeitz, Rachele Sanfelici, and Marlene Rosen
- Subjects
Adult ,Male ,Psychosis ,Time Factors ,MEDLINE ,Medizin ,Comorbidity ,Machine learning ,computer.software_genre ,Sensitivity and Specificity ,Workflow ,Machine Learning ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Text mining ,Medicine ,Humans ,Online First ,Generalizability theory ,Longitudinal Studies ,610 Medicine & health ,Depression (differential diagnoses) ,Original Investigation ,Depressive Disorder ,business.industry ,Research ,medicine.disease ,Prognosis ,030227 psychiatry ,Featured ,Europe ,Psychiatry and Mental health ,Clinical research ,Psychotic Disorders ,Schizophrenia ,Female ,Artificial intelligence ,Disease Susceptibility ,business ,computer ,Neurocognitive ,030217 neurology & neurosurgery ,Comments ,Follow-Up Studies - Abstract
This prognostic study evaluates whether psychosis transition can be predicted in patients with clinical high-risk syndromes or recent-onset depression by multimodal machine learning that optimally integrates clinical and neurocognitive data, structural magnetic resonance imaging, and polygenic risk scores for schizophrenia., Key Points Question Can a transition to psychosis be predicted in patients with clinical high-risk states or recent-onset depression by optimally integrating clinical, neurocognitive, neuroimaging, and genetic information with clinicians’ prognostic estimates? Findings In this prognostic study of 334 patients and 334 control individuals, machine learning models sequentially combining clinical and biological data with clinicians’ estimates correctly predicted disease transitions in 85.9% of cases across geographically distinct patient populations. The clinicians’ lack of prognostic sensitivity, as measured by a false-negative rate of 38.5%, was reduced to 15.4% by the sequential prognostic model. Meaning These findings suggest that an individualized prognostic workflow integrating artificial and human intelligence may facilitate the personalized prevention of psychosis in young patients with clinical high-risk syndromes or recent-onset depression., Importance Diverse models have been developed to predict psychosis in patients with clinical high-risk (CHR) states. Whether prediction can be improved by efficiently combining clinical and biological models and by broadening the risk spectrum to young patients with depressive syndromes remains unclear. Objectives To evaluate whether psychosis transition can be predicted in patients with CHR or recent-onset depression (ROD) using multimodal machine learning that optimally integrates clinical and neurocognitive data, structural magnetic resonance imaging (sMRI), and polygenic risk scores (PRS) for schizophrenia; to assess models’ geographic generalizability; to test and integrate clinicians’ predictions; and to maximize clinical utility by building a sequential prognostic system. Design, Setting, and Participants This multisite, longitudinal prognostic study performed in 7 academic early recognition services in 5 European countries followed up patients with CHR syndromes or ROD and healthy volunteers. The referred sample of 167 patients with CHR syndromes and 167 with ROD was recruited from February 1, 2014, to May 31, 2017, of whom 26 (23 with CHR syndromes and 3 with ROD) developed psychosis. Patients with 18-month follow-up (n = 246) were used for model training and leave-one-site-out cross-validation. The remaining 88 patients with nontransition served as the validation of model specificity. Three hundred thirty-four healthy volunteers provided a normative sample for prognostic signature evaluation. Three independent Swiss projects contributed a further 45 cases with psychosis transition and 600 with nontransition for the external validation of clinical-neurocognitive, sMRI-based, and combined models. Data were analyzed from January 1, 2019, to March 31, 2020. Main Outcomes and Measures Accuracy and generalizability of prognostic systems. Results A total of 668 individuals (334 patients and 334 controls) were included in the analysis (mean [SD] age, 25.1 [5.8] years; 354 [53.0%] female and 314 [47.0%] male). Clinicians attained a balanced accuracy of 73.2% by effectively ruling out (specificity, 84.9%) but ineffectively ruling in (sensitivity, 61.5%) psychosis transition. In contrast, algorithms showed high sensitivity (76.0%-88.0%) but low specificity (53.5%-66.8%). A cybernetic risk calculator combining all algorithmic and human components predicted psychosis with a balanced accuracy of 85.5% (sensitivity, 84.6%; specificity, 86.4%). In comparison, an optimal prognostic workflow produced a balanced accuracy of 85.9% (sensitivity, 84.6%; specificity, 87.3%) at a much lower diagnostic burden by sequentially integrating clinical-neurocognitive, expert-based, PRS-based, and sMRI-based risk estimates as needed for the given patient. Findings were supported by good external validation results. Conclusions and Relevance These findings suggest that psychosis transition can be predicted in a broader risk spectrum by sequentially integrating algorithms’ and clinicians’ risk estimates. For clinical translation, the proposed workflow should undergo large-scale international validation.
- Published
- 2021
- Full Text
- View/download PDF
23. Pattern classification as decision support tool in antipsychotic treatment algorithms
- Author
-
Alexandra I. Korda, Stefan Borgwardt, and Christina Andreou
- Subjects
0301 basic medicine ,Decision support system ,business.industry ,medicine.medical_treatment ,Personalized treatment ,High variability ,Antipsychotic treatment ,medicine.disease ,Machine Learning ,03 medical and health sciences ,Statistical classification ,030104 developmental biology ,0302 clinical medicine ,Developmental Neuroscience ,Neurology ,Psychotic Disorders ,Schizophrenia ,medicine ,Humans ,Antipsychotic ,business ,Algorithm ,030217 neurology & neurosurgery ,Algorithms ,Antipsychotic Agents - Abstract
Pattern classification aims to establish a new approach in personalized treatment. The scope is to tailor treatment on individual characteristics during all phases of care including prevention, diagnosis, treatment, and clinical outcome. In psychotic disorders, this need results from the fact that a third of patients with psychotic symptoms do not respond to antipsychotic treatment and are described as having treatment-resistant disorders. This, in addition to the high variability of treatment responses among patients, enhances the need of applying advanced classification algorithms to identify antipsychotic treatment patterns. This review comprehensively summarizes advancements and challenges of pattern classification in antipsychotic treatment response to date and aims to introduce clinicians and researchers to the challenges of including pattern classification into antipsychotic treatment decision algorithms.
- Published
- 2020
24. EEG Microstate Differences in Medicated vs. Medication-Naïve First-Episode Psychosis Patients
- Author
-
Amatya J, Mackintosh, Stefan, Borgwardt, Erich, Studerus, Anita, Riecher-Rössler, Renate, de Bock, and Christina, Andreou
- Subjects
Psychiatry ,schizophrenia ,resting-state ,untreated ,unmedicated ,neuroleptic ,electroencephalography ,pathophysiology ,Original Research ,antipsychotic - Abstract
There has been considerable interest in the role of synchronous brain activity abnormalities in the pathophysiology of psychotic disorders and their relevance for treatment; one index of such activity are EEG resting-state microstates. These reflect electric field configurations of the brain that persist over 60–120 ms time periods. A set of quasi-stable microstates classes A, B, C, and D have been repeatedly identified across healthy participants. Changes in microstate parameters coverage, duration and occurrence have been found in medication-naïve as well as medicated patients with psychotic disorders compared to healthy controls. However, to date, only two studies have directly compared antipsychotic medication effects on EEG microstates either pre- vs. post-treatment or between medicated and unmedicated chronic schizophrenia patients. The aim of this study was therefore to directly compare EEG resting-state microstates between medicated and medication-naïve (untreated) first-episode (FEP) psychosis patients (mFEP vs. uFEP). We used 19-channel clinical EEG recordings to compare temporal parameters of four prototypical microstate classes (A–D) within an overall sample of 47 patients (mFEP n = 17; uFEP n = 30). The results demonstrated significant decreases of microstate class A and significant increases of microstate class B in mFEP compared to uFEP. No significant differences between groups were found for microstate classes C and D. Further studies are needed to replicate these results in longitudinal designs that assess antipsychotic medication effects on neural networks at the onset of the disorder and over time during illness progression. As treatment response and compliance in FEP patients are relatively low, such studies could contribute to better understand treatment outcomes and ultimately improve treatment strategies.
- Published
- 2020
25. Alterations of oscillatory neuronal activity during reward processing in schizophrenia
- Author
-
Gregor Leicht, Till Nafe, Christina Andreou, Jonas Rauh, Daniel Schöttle, Christoph Mulert, Stjepan Curic, Saskia Steinmann, Felix Nägele, and Paul Alexander Schauer
- Subjects
Psychosis ,Electroencephalography ,Tonic (physiology) ,03 medical and health sciences ,Reward system ,0302 clinical medicine ,Reward ,Dopamine ,Medicine ,Premovement neuronal activity ,Humans ,Biological Psychiatry ,Brain Mapping ,medicine.diagnostic_test ,business.industry ,Dopaminergic ,medicine.disease ,030227 psychiatry ,Psychiatry and Mental health ,Electrophysiology ,Gambling ,Schizophrenia ,business ,Neuroscience ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Objectives Reward system dysfunctions are considered to be a pathophysiological mechanism in schizophrenia. Electrophysiological studies of reward system functions have identified frequency-specific brain networks for the processing of positive (high-beta frequency) and negative (theta frequency) events. Remarkably, midbrain dopaminergic signalling also includes theta and high-beta frequency modes, which have been assumed to reflect tonic and phasic dopamine responses, respectively. The aim of the present study was to identify alterations of oscillatory responses to reward feedback in patients with schizophrenia. Methods Seventeen patients with schizophrenia and 18 healthy controls performed a gambling task during recording of 64-channel electroencephalography. The theta and high-beta band total power were investigated in response to feedback events depending on feedback valence (loss or gain) and magnitude (5 vs. 25 points). Results Both the increase of theta oscillatory activity in response to loss feedback (compared to gain feedback) and the increase of high-beta oscillatory activity in response to gain feedback (compared to loss feedback) were reduced in patients. The difference in high-beta responses to gain versus loss feedback in patients was associated with the severity of negative symptoms. Conclusions Our findings are consistent with current models of reward system dysfunction in schizophrenia, and indicate deficits in both cortical tonic and subcortical phasic dopamine activity, consistent with the complex dopaminergic abnormalities in schizophrenia.
- Published
- 2020
26. EEG microstates as biomarker for psychosis in ultra-high-risk patients
- Author
-
Anita Riecher-Rössler, Amatya Johanna Mackintosh, Stefan Borgwardt, Renate de Bock, Christina Andreou, and Franziska Maier
- Subjects
Psychosis ,medicine.medical_specialty ,Electroencephalography ,Ultra high risk ,Audiology ,Article ,lcsh:RC321-571 ,Cellular and Molecular Neuroscience ,Ministate ,Risk Factors ,medicine ,Humans ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Biological Psychiatry ,Psychopathology ,medicine.diagnostic_test ,business.industry ,medicine.disease ,Psychiatry and Mental health ,EEG microstates ,medicine.anatomical_structure ,Psychotic Disorders ,Schizophrenia ,Scalp ,Biomarker (medicine) ,sense organs ,business ,Biomarkers ,Neuroscience - Abstract
Resting-state EEG microstates are brief (50–100 ms) periods, in which the spatial configuration of scalp global field power remains quasi-stable before rapidly shifting to another configuration. Changes in microstate parameters have been described in patients with psychotic disorders. These changes have also been observed in individuals with a clinical or genetic high risk, suggesting potential usefulness of EEG microstates as a biomarker for psychotic disorders. The present study aimed to investigate the potential of EEG microstates as biomarkers for psychotic disorders and future transition to psychosis in patients at ultra-high-risk (UHR). We used 19-channel clinical EEG recordings and orthogonal contrasts to compare temporal parameters of four normative microstate classes (A–D) between patients with first-episode psychosis (FEP; n = 29), UHR patients with (UHR-T; n = 20) and without (UHR-NT; n = 34) later transition to psychosis, and healthy controls (HC; n = 25). Microstate A was increased in patients (FEP & UHR-T & UHR-NT) compared to HC, suggesting an unspecific state biomarker of general psychopathology. Microstate B displayed a decrease in FEP compared to both UHR patient groups, and thus may represent a state biomarker specific to psychotic illness progression. Microstate D was significantly decreased in UHR-T compared to UHR-NT, suggesting its potential as a selective biomarker of future transition in UHR patients.
- Published
- 2020
- Full Text
- View/download PDF
27. The role of effective connectivity between the task-positive and task-negative network for evidence gathering [Evidence gathering and connectivity]
- Author
-
Jonas Rauh, Katharina Kolbeck, Steffen Moritz, Christina Andreou, Christoph Mulert, Saskia Steinmann, and Gregor Leicht
- Subjects
Adult ,Male ,Evidence gathering ,Cognitive Neuroscience ,Schizophrenia (object-oriented programming) ,050105 experimental psychology ,Task (project management) ,Thinking ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Humans ,0501 psychology and cognitive sciences ,Default mode network ,Brain Mapping ,05 social sciences ,Psychophysiological Interaction ,Probabilistic logic ,Brain ,Contrast (statistics) ,Middle Aged ,Magnetic Resonance Imaging ,Neurology ,Jumping to conclusions ,Female ,Nerve Net ,Psychology ,030217 neurology & neurosurgery ,Cognitive psychology - Abstract
Reports linking a 'jumping-to-conclusions' bias to delusions have led to growing interest in the neurobiological correlates of probabilistic reasoning. Several brain areas have been implicated in probabilistic reasoning; however, findings are difficult to integrate into a coherent account. The present study aimed to provide additional evidence by investigating, for the first time, effective connectivity among brain areas involved in different stages of evidence gathering. We investigated evidence gathering in 25 healthy individuals using fMRI and a new paradigm (Box Task) designed such as to minimize the effects of cognitive effort and reward processing. Decisions to collect more evidence ('draws') were contrasted to decisions to reach a final choice ('conclusions') with respect to BOLD activity. Psychophysiological interaction analysis was used to investigate effective connectivity. Conclusion events were associated with extensive brain activations in widely distributed brain areas associated with the task-positive network. In contrast, draw events were characterized by higher activation in areas assumed to be part of the task-negative network. Effective connectivity between the two networks decreased during draws and increased during conclusion events. Our findings indicate that probabilistic reasoning may depend on the balance between the task-positive and task-negative network, and that shifts in connectivity between the two may be crucial for evidence gathering. Thus, abnormal connectivity between the two systems may significantly contribute to the jumping-to-conclusions bias.
- Published
- 2018
28. Social cognition in the course of psychosis and its correlation with biomarkers in a male cohort
- Author
-
Aikaterini Tsoura, Evangelos Karanikas, Evangelos Ntouros, Vasilios P. Bozikas, Christina Andreou, Georgios Garyfallos, and Georgios Floros
- Subjects
Adult ,Male ,Psychosis ,Adolescent ,Hydrocortisone ,Cognitive Neuroscience ,Emotions ,Theory of Mind ,behavioral disciplines and activities ,Cohort Studies ,Young Adult ,03 medical and health sciences ,Cognition ,0302 clinical medicine ,Social cognition ,Emotion perception ,Theory of mind ,medicine ,Humans ,Social Behavior ,Social perception ,medicine.disease ,030227 psychiatry ,Psychiatry and Mental health ,Cross-Sectional Studies ,Psychotic Disorders ,Social Perception ,Schizophrenia ,Cohort ,Schizophrenic Psychology ,Inflammation Mediators ,Cognition Disorders ,Psychology ,Biomarkers ,030217 neurology & neurosurgery ,Clinical psychology - Abstract
Patients diagnosed with schizophrenia display deficits in Theory of Mind (ToM) and Emotion Perception (EP) even before the appearance of full-blown symptomatology.We evaluated ToM and EP in a male cohort consisting of 25 First Episode Psychosis (FEP) and 16 relapsed schizophrenic patients (CHRON) compared to 12 subjects in Ultra-high Risk (UHR) and 23 healthy controls (CTR). Furthermore, we measured the levels of Cortisol, Insulin like Growth Factor (IGF-1), TNF-a, TNF-b and several interleukins as potential biomarkers.Deficits in EP and ToM were found in FEP, CHRON patients and UHR subjects compared to CTR. The impairments in these two domains seem to follow different patterns in the course of psychosis. EP was more impaired in subjects with a longer history of symptomatology whereas there was no statistically significant difference regarding ToM. On the other hand IL-4 was the only biomarker correlated to ToM and EP scores in two different samples of our study.Social Cognition (SC) domains are impaired in patients with psychosis as well as in UHR subjects compared to healthy controls. There are differences in the progress of ToM and EP deficits in the course of psychosis. Interleukins as IL-4 could correlate to SC.
- Published
- 2018
29. Gender differences in first self‐perceived signs and symptoms in patients with an at‐risk mental state and first‐episode psychosis
- Author
-
Astrid Navarra, Erich Studerus, Laura Egloff, Martina Papmeyer, Christina Andreou, Anita Riecher-Rössler, Sarah Ittig, S. Menghini-Müller, and Ulrike Heitz
- Subjects
Adult ,Male ,Risk ,Psychosis ,Adolescent ,Hallucinations ,Psychometrics ,Prodromal Symptoms ,Signs and symptoms ,Logistic regression ,Young Adult ,03 medical and health sciences ,Sex Factors ,0302 clinical medicine ,Risk Factors ,First episode psychosis ,Brief Psychiatric Rating Scale ,Humans ,Medicine ,Self perceived ,Biological Psychiatry ,Retrospective Studies ,Psychiatric Status Rating Scales ,business.industry ,At risk mental state ,Fear ,medicine.disease ,Anxiety Disorders ,Self Concept ,030227 psychiatry ,Psychiatry and Mental health ,Early Diagnosis ,Psychotic Disorders ,Social Isolation ,Anxiety ,Female ,Pshychiatric Mental Health ,medicine.symptom ,business ,Switzerland ,030217 neurology & neurosurgery ,Psychopathology ,Clinical psychology - Abstract
AIM Gender differences in the current symptomatology of patients with psychotic disorders have previously been described in the literature. However, it has not yet been investigated whether gender differences exist in the very first self-perceived signs or symptoms of illness onset. The aim of this study was to investigate this aspect in at-risk mental state (ARMS) and first-episode psychosis (FEP) patients. METHODS ARMS and FEP were recruited via the early detection of psychosis (FePsy) clinic Basel, Switzerland. The Basel Interview for Psychosis (BIP) was used to retrospectively assess the first 3 self-perceived signs and symptoms at illness onset. Differences between gender and patient groups on single item and symptom cluster levels were analysed using logistic regression models. RESULTS One-hundred-thirty six ARMS (91 men, 45 women) and 89 FEP patients (63 men, 26 women) could be recruited for this study. On a single item level, women more frequently reported "unusual anxiety, fears" and men (at a trend level) "social withdrawal" as being among their 3 first self-perceived symptoms, independent of diagnostic group. On the symptom cluster level, women more frequently reported "increased worrying/anxiety" and (sub-threshold) "hallucinations", independent of diagnostic group. Problems with "thinking, concentration" were reported more frequently by men in the ARMS group only. CONCLUSION Our results suggest that only few and relatively small gender differences exist in the first self-perceived signs and symptoms. While men initially mainly notice negative/cognitive symptoms, women first notice (sub-threshold) positive and affective symptoms.
- Published
- 2017
30. Brain Network Architecture Intricately Linked to Morphological Abnormalities in Major Psychiatric Disorders
- Author
-
Vince D. Calhoun, Edith Pomarol-Clotet, Erich Seifritz, Vaughan J. Carr, Stanley V. Catts, Alfonso Gonzalez-Valderrama, Juan Undurraga, Raymond Salvador, André Schmidt, Ellen Ji, Christos Pantelis, Diana Tordesillas-Gutiérrez, Tilo Kircher, Valentina Ciullo, Assen Jablensky, Stefan Kaiser, Stefan Borgwardt, Yann Quidé, Bryan J. Mowry, Kang Sim, Melissa J. Green, Sara Larivière, Theo G.M. van Erp, Foivos Georgiadis, Aristotle N. Voineskos, Stephanie Homan, A Krug, Boris C. Bernhardt, Patricia T. Michie, Christina Andreou, Philipp Homan, Benedicto Crespo-Facorro, Matthias Kirschner, Gianfranco Spalletta, Fabrizio Piras, Nicolas Crossley, Paul M. Thompson, Nerisa Banaj, Jessica A. Turner, and Frans Henskens
- Subjects
Brain network ,medicine.medical_specialty ,Human Connectome Project ,Schizophrenia (object-oriented programming) ,medicine ,Mega analysis ,Bipolar disorder ,Architecture ,Psychology ,medicine.disease ,Psychiatry ,Biological Psychiatry - Published
- 2021
31. Embracing Psychosis: A Cognitive Insight Intervention Improves Personal Narratives and Meaning-Making in Patients With Schizophrenia
- Author
-
Candelaria Mahlke, Steffen Moritz, Friederike Ruppelt, Thomas Bock, Christina Andreou, Stefan Westermann, and Paul H. Lysaker
- Subjects
Adult ,Male ,Psychosis ,Psychotherapist ,medicine.medical_treatment ,Metacognition ,Young Adult ,03 medical and health sciences ,Metacognitive therapy ,0302 clinical medicine ,Outcome Assessment, Health Care ,medicine ,Humans ,Suicidal ideation ,Cognitive Behavioral Therapy ,Neuropsychology ,Cognition ,Middle Aged ,medicine.disease ,Cognitive Remediation ,Self Concept ,030227 psychiatry ,Cognitive behavioral therapy ,Psychiatry and Mental health ,Psychotic Disorders ,Cognitive remediation therapy ,Female ,medicine.symptom ,Psychology ,030217 neurology & neurosurgery ,Follow-Up Studies ,Regular Articles ,Clinical psychology - Abstract
Schizophrenia is a complex psychiatric disorder with unknown and presumably heterogeneous etiology. While the disorder can have various outcomes, research is predominantly “deficit-oriented” emphasizing the hardship that the disorder inflicts on sufferers as well as their families and society. Beyond symptom reduction, imparting patients with hope and meaning in life is increasingly considered an important treatment target, which may raise self-esteem, and reduce self-stigma and suicidal ideation. The present study compared a psychotherapeutic treatment aimed at improving cognitive insight, individualized metacognitive intervention (MCT+), with an active control in order to elucidate if personal meaning-making and hope can be improved in patients with psychosis across time. A total of 92 patients were randomized to either individualized metacognitive therapy (MCT+) or CogPack (neuropsychological training) and followed up for up to 6 months. The “Subjective Sense in Psychosis Questionnaire” (SUSE) was administered which covers different salutogenetic vs pathogenetic views of the disorder, valence of symptom experiences and the consequences of psychosis. Patients in the MCT+ group showed a significant positive shift in attitudes towards the consequences of their illness over time relative to patients in the active control condition. There was some evidence that MCT+ also enhanced meaning-making. The perceived negative consequences of psychosis were highly correlated with depression and low self-esteem, as well as suicidality. The study shows that a cognitive insight training can improve meaning-making in patients and help them come to terms with their diagnosis.
- Published
- 2017
32. Glutamatergic deficit and schizophrenia-like negative symptoms: new evidence from ketamine-induced mismatch negativity alterations in healthy male humans
- Author
-
Gregor Leicht, Iris Eichler, Lars Eichler, Christina Andreou, Nenad Polomac, Ileana L. Hanganu-Opatz, Saskia Steinmann, Christian Zöllner, Stephanie Thiebes, Christoph Mulert, Jürgen Gallinat, and Stjepan Curic
- Subjects
Adult ,Male ,medicine.medical_specialty ,Glutamic Acid ,Mismatch negativity ,Audiology ,Electroencephalography ,Receptors, N-Methyl-D-Aspartate ,behavioral disciplines and activities ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,mental disorders ,medicine ,Humans ,Middle frontal gyrus ,Single-Blind Method ,Pharmacology (medical) ,Ketamine ,Psychiatry ,Biological Psychiatry ,medicine.diagnostic_test ,Positive and Negative Syndrome Scale ,Brain ,medicine.disease ,Healthy Volunteers ,030227 psychiatry ,Psychiatry and Mental health ,Schizophrenia ,Posterior cingulate ,Evoked Potentials, Auditory ,Psychology ,Excitatory Amino Acid Antagonists ,psychological phenomena and processes ,030217 neurology & neurosurgery ,Research Paper ,Psychopathology ,medicine.drug - Abstract
Background: Targeting the N-methyl-d-aspartate receptor (NMDAR) is a major translational approach for treating negative symptoms of schizophrenia. Ketamine comprehensively produces schizophrenia-like symptoms, such as positive, cognitive and negative symptoms in healthy volunteers. The amplitude of the mismatch negativity (MMN) is known to be significantly reduced not only in patients with schizophrenia, but also in healthy controls receiving ketamine. Accordingly, it was the aim of the present study to investigate whether changes of MMN amplitudes during ketamine administration are associated with the emergence of schizophrenia-like negative symptoms in healthy volunteers. Methods: We examined the impact of ketamine during an MMN paradigm with 64-channel electroencephalography (EEG) and assessed the psychopathological status using the Positive and Negative Syndrome Scale (PANSS) in healthy male volunteers using a single-blind, randomized, placebo-controlled crossover design. Low-resolution brain electromagnetic tomography was used for source localization. Results: Twenty-four men were included in our analysis. Significant reductions of MMN amplitudes and an increase in all PANSS scores were identified under the ketamine condition. Smaller MMN amplitudes were specifically associated with more pronounced negative symptoms. Source analysis of MMN generators indicated a significantly reduced current source density (CSD) under the ketamine condition in the primary auditory cortex, the posterior cingulate and the middle frontal gyrus. Limitations: The sample included only men within a tight age range of 20–32 years. Conclusion: The MMN might represent a biomarker for negative symptoms in schizophrenia related to an insufficient NMDAR system and could be used to identify patients with schizophrenia with negative symptoms due to NMDAR dysfunction.
- Published
- 2017
33. Moderators of treatment efficacy in individualized metacognitive training for psychosis (MCT+)
- Author
-
Steffen Moritz, Christina Andreou, Letizia Leanza, Erich Studerus, and Vasilis P. Bozikas
- Subjects
Adult ,Male ,Psychosis ,Adolescent ,Psychological intervention ,Experimental and Cognitive Psychology ,Delusions ,law.invention ,Young Adult ,Arts and Humanities (miscellaneous) ,Randomized controlled trial ,law ,medicine ,Humans ,Aged ,Cognitive Behavioral Therapy ,Cognition ,Middle Aged ,medicine.disease ,Cognitive bias ,Psychiatry and Mental health ,Clinical Psychology ,Treatment Outcome ,Psychotic Disorders ,Schizophrenia ,Cognitive remediation therapy ,Jumping to conclusions ,Quality of Life ,Female ,Psychology ,Clinical psychology - Abstract
Background and objectives Individualized Metacognitive Training (MCT+) is a manualized intervention designed to improve delusional severity by reducing delusion-associated cognitive biases such as jumping-to-conclusions. Increased interest in personalized medicine stipulates the identification of patients who are more likely to benefit from specialized interventions. The present study aimed to explore baseline moderators of MCT+ efficacy on delusions and overall positive symptoms in psychosis. Methods We analyzed data from a randomized rater-blind controlled trial, in which 92 patients with psychotic disorders and current or past delusions were randomly assigned to either MCT+ or CogPack®, a cognitive remediation software. Baseline moderator variables consisted of jumping-to-conclusions, cognitive insight, quality of life, self-esteem, selective attention, and patients’ attitudes towards their symptoms. Linear mixed-effects models were applied to investigate specific moderators of MCT+ efficacy. Results In MCT+ relative to CogPack, presence of a jumping-to-conclusions bias, a lowered decision threshold, and low self-esteem were associated with larger improvements in delusional severity and/or overall positive symptoms over time. Subjective reasoning style and insight, as well as subjective attitudes towards psychosis, did not moderate the treatment efficacy of MCT+ relative to CogPack. Limitations Participation of both treatment groups in group MCT as a part of standard care, possibly leading to additional effects on delusional severity. Conclusions Patients with low self-esteem and those who are prone to jumping-to-conclusions seem to particularly benefit from MCT+. Our results can help inform clinical practice as they provide specific criteria for selecting patients for whom MCT+ is most appropriate.
- Published
- 2019
34. Predictors of study drop-out and service disengagement in patients at clinical high risk for psychosis
- Author
-
Christina Andreou, Letizia Leanza, Leonie Seiler, Anita Riecher-Rössler, Erich Studerus, Amatya Johanna Mackintosh, and Katharina Beck
- Subjects
Adult ,Male ,medicine.medical_specialty ,Psychosis ,Health (social science) ,Social Psychology ,Adolescent ,Psychometrics ,Epidemiology ,Proxy (climate) ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Predictive Value of Tests ,Risk Factors ,medicine ,Humans ,Attrition ,030212 general & internal medicine ,Prospective Studies ,Disengagement theory ,Psychiatry ,Survival analysis ,Demography ,Service (business) ,business.industry ,At risk mental state ,medicine.disease ,030227 psychiatry ,Psychiatry and Mental health ,Psychotic Disorders ,Socioeconomic Factors ,Patient Compliance ,Female ,business ,Switzerland - Abstract
Study drop-out during follow-up and service disengagement frequently occur in patients at clinical high risk for psychosis (CHR-P). However, little is known about their predictors. Therefore, we aimed to analyze the rate and reasons for drop-out and service disengagement in CHR-P patients and investigate their sociodemographic and clinical predictors. Data from 200 patients of the prospective Fruherkennung von Psychosen (FePsy) study were analyzed with competing risks survival models, considering drop-out and transition to psychosis as competing events. To investigate whether symptoms changed immediately before drop-out, t tests were applied. Thirty-six percent of patients dropped out within 5 years. Almost all drop-outs also disengaged from our service. Hence, study drop-out was used as a proxy for service disengagement. Patients with more severe baseline disorganized symptoms and a late inclusion into the study were significantly more likely to disengage. Immediately before disengagement, there was significant improvement in negative symptoms only. A considerable proportion of CHR-P patients disengaged from our clinical study and service. Patients who were included during a later study period with more assessments disengaged more often, which might have been due to more frequent invitations to follow-up assessments and thereby increasing participation burden. Hence, our study provides a cautionary note on high-frequency follow-up assessments. Larger-scale studies evaluating predictors on multiple domains would help to further elucidate drop-out and disengagement.
- Published
- 2019
35. Clinical and functional ultra-long-term outcome of patients with a clinical high risk (CHR) for psychosis
- Author
-
Andor E. Simon, Letizia Leanza, Stefan Borgwardt, Katharina Beck, Anita Riecher-Rössler, Erich Studerus, Laura Egloff, and Christina Andreou
- Subjects
Adult ,Male ,Psychosis ,Pediatrics ,medicine.medical_specialty ,Adolescent ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Medicine ,Humans ,Longitudinal Studies ,Risk status ,business.industry ,At risk mental state ,Middle Aged ,medicine.disease ,Comorbidity ,030227 psychiatry ,Psychiatry and Mental health ,Psychotic Disorders ,Disease Progression ,Female ,business ,Psychosocial ,030217 neurology & neurosurgery - Abstract
Background:Few studies have followed up patients with a clinical high risk (CHR) for psychosis for more than 2–3 years. We aimed to investigate the rates and baseline predictors for remission from CHR and transition to psychosis over a follow-up period of up to 16 years. Additionally, we examined the clinical and functional long-term outcome of CHR patients who did not transition.Methods:We analyzed the long-term course of CHR patients that had been included in the longitudinal studies “Früherkennung von Psychosen” (FePsy) or “Bruderholz” (BHS). Those patients who had not transitioned to psychosis during the initial follow-up periods (2/5 years), were invited for additional follow-ups.Results:Originally, 255 CHR patients had been included. Of these, 47 had transitioned to psychosis during the initial follow-ups. Thus, 208 were contacted for the long-term follow-up, of which 72 (34.6%) participated. From the original sample of 255, 26%, 31%, 35%, and 38% were estimated to have transitioned after 3, 5, 10, and 16 years, respectively, and 51% had remitted from their high risk status at the latest follow-up. Better psychosocial functioning at baseline was associated with a higher rate of remission. Of the 72 CHR patients re-assessed at long-term follow-up, 60 had not transitioned, but only 28% of those were fully recovered clinically and functionally.Conclusions:Our study shows the need for follow-ups and clinical attention longer than the usual 2–3 years as there are several CHR patients with later transitions and only a minority of CHR those without transition fully recovers.
- Published
- 2019
36. Psychotische Störungen: Früherkennung und -intervention
- Author
-
Barbara Bailey, Stefan Borgwardt, and Christina Andreou
- Abstract
Dieser Artikel zeigt auf, wie Fachpersonen, die im Erstkontakt mit psychosegefahrdeten Menschen zu tun haben, den klinischen Verlauf und die Prognose konkret verbessern konnen.
- Published
- 2019
37. Troubles psychotiques: dépistage et intervention précoces
- Author
-
Christina Andreou, Stefan Borgwardt, and Barbara Bailey
- Abstract
Cet article montre comment les professionnels qui ont le premier contact avec les personnes a risque de psychose peuvent ameliorer concretement l’evolution clinique et le pronostic.
- Published
- 2019
38. Plasma and serum brain-derived neurotrophic factor (BDNF) levels and their association with neurocognition in at-risk mental state, first episode psychosis and chronic schizophrenia patients
- Author
-
Ulrike Heitz, Martina Papmeyer, Erich Studerus, Sarah Ittig, Tobias Vogel, Anita Riecher-Rössler, Stefan Borgwardt, Laura Egloff, Christina Andreou, Marc Graf, and Anne Eckert
- Subjects
Adult ,Male ,Oncology ,Psychosis ,medicine.medical_specialty ,Neuropsychological Tests ,Executive Function ,Young Adult ,03 medical and health sciences ,Cognition ,0302 clinical medicine ,Internal medicine ,medicine ,Humans ,Neuropsychological assessment ,Biological Psychiatry ,Brain-derived neurotrophic factor ,medicine.diagnostic_test ,business.industry ,Brain-Derived Neurotrophic Factor ,Neuropsychology ,At risk mental state ,medicine.disease ,030227 psychiatry ,Psychiatry and Mental health ,Cross-Sectional Studies ,Memory, Short-Term ,Psychotic Disorders ,nervous system ,Schizophrenia ,Regression Analysis ,Female ,Verbal memory ,Cognition Disorders ,business ,Neurocognitive ,Switzerland - Abstract
Objectives: Brain-derived neurotrophic factor (BDNF) is involved in numerous cognitive processes. Since cognitive deficits are a core feature of psychotic disorders, the investigation of BDNF levels in psychosis and their correlation with cognition has received increased attention. However, there are no studies investigating BDNF levels in individuals with an at-risk mental state (ARMS) for psychosis. Hence, the aims of the present study were: (1) assessing peripheral BDNF levels across different (potential) stages of psychosis; (2) investigating their association with cognition. Methods: Plasma and serum BDNF levels and neuropsychological performance were assessed in 16 ARMS, six first-episode psychosis (FEP), and 11 chronic schizophrenia (CS) patients. Neuropsychological assessment covered intelligence, verbal memory, working memory, attention and executive functioning. Results: Both plasma and serum BDNF levels were highest in CS, intermediate in FEP and lowest in ARMS. Multiple regression analysis revealed a significant positive association of plasma BDNF levels with planning ability across all groups. Conclusions: The lower peripheral BDNF levels in ARMS compared to FEP and CS might point towards an important drop of this neurotrophin prior to the onset of frank psychosis. The associations of peripheral BDNF with planning-abilities match previous findings.
- Published
- 2019
- Full Text
- View/download PDF
39. Association Splitting: A randomized controlled trial of a new method to reduce craving among inpatients with alcohol dependence
- Author
-
Brooke C. Schneider, Steffen Moritz, Christina Andreou, Jens Reimer, Lena Jelinek, and Birgit Hottenrott
- Subjects
Adult ,Male ,medicine.medical_specialty ,Alcohol Drinking ,Personality Inventory ,medicine.medical_treatment ,media_common.quotation_subject ,Pilot Projects ,Craving ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,Randomized controlled trial ,law ,medicine ,Humans ,Psychiatry ,Biological Psychiatry ,media_common ,Psychiatric Status Rating Scales ,Inpatients ,Cognitive Intervention ,Cognitive Behavioral Therapy ,Addiction ,Alcohol dependence ,Middle Aged ,Exercise Therapy ,030227 psychiatry ,Cognitive behavioral therapy ,Alcoholism ,Psychiatry and Mental health ,Treatment Outcome ,Compulsive behavior ,Compulsive Behavior ,Cognitive therapy ,Female ,medicine.symptom ,Psychology ,030217 neurology & neurosurgery - Abstract
Association Splitting, a novel cognitive intervention, was tested in patients with alcohol dependence as an add-on intervention in an initial randomized controlled trial. Preliminary support for Association Splitting has been found in patients with obsessive-compulsive disorder, as well as in an online pilot study of patients with alcohol use disorders. The present variant sought to reduce craving by strengthening neutral associations with alcohol-related stimuli, thus, altering cognitive networks. Eighty-four inpatients with verified diagnoses of alcohol dependence, who were currently undergoing inpatient treatment, were randomly assigned to Association Splitting or Exercise Therapy. Craving was measured at baseline, 4-week follow-up, and six months later with the Obsessive-Compulsive Drinking Scale (primary outcome) and the Alcohol Craving Questionnaire. There was no advantage for Association Splitting after three treatment sessions relative to Exercise Therapy. Among Association Splitting participants, 51.9% endorsed a subjective decline in craving and 88.9% indicated that they would use Association Splitting in the future. Despite high acceptance, an additional benefit of Association Splitting beyond standard inpatient treatment was not found. Given that participants were concurrently undergoing inpatient treatment and Association Splitting has previously shown moderate effects, modification of the study design may improve the potential to detect significant effects in future trials.
- Published
- 2016
40. The role of attachment anxiety in the relationship between childhood trauma and schizophrenia-spectrum psychosis
- Author
-
George Garyfallos, Christina Andreou, Vasilios P. Bozikas, Agorastos Agorastos, Yanni Malliaris, Stergios Kaprinis, and Stylianos Chatziioannidis
- Subjects
Adult ,Male ,Psychosis ,Hallucinations ,Population ,Anxiety ,03 medical and health sciences ,0302 clinical medicine ,Risk Factors ,Attachment theory ,medicine ,Humans ,education ,Psychological abuse ,Biological Psychiatry ,education.field_of_study ,Psychopathology ,business.industry ,Middle Aged ,medicine.disease ,Object Attachment ,030227 psychiatry ,Psychiatry and Mental health ,Physical abuse ,Sexual abuse ,Adult Survivors of Child Adverse Events ,Psychotic Disorders ,Schizophrenia ,Case-Control Studies ,Female ,Schizophrenic Psychology ,business ,030217 neurology & neurosurgery ,Clinical psychology - Abstract
Childhood trauma (CT) is a comprehensive concept encompassing experiences of sexual, physical, and emotional abuse, and neglect during childhood and adolescence. Patients with schizophrenia-spectrum psychosis (SSP) display higher rates of CT than healthy controls. Among the potential mediators of this association, insecure attachment has gained attention and empirical validation. The present study aimed to extend existing knowledge on this field by exploring the role of the two attachment dimensions, attachment anxiety and attachment avoidance, in the CT-SSP association. A clinical sample of 63 SSP inpatients was compared to a healthy control group on CT and attachment style measures. Correlations between CT, attachment dimensions and psychopathology were sought. Mediation analyses were also performed to examine whether attachment anxiety and/or attachment avoidance mediated the CT-SSP association. Patients displayed higher rates of CT and insecure attachment than controls. Attachment anxiety and severity of Mother Antipathy were linked to severity of hallucinations. Attachment anxiety was recognized as the sole mediator of the CT-SSP association. Our findings suggest that individuals with severe CT and increased attachment anxiety represent a risk population warranting early clinical attention, regular monitoring and tailored therapeutic interventions aimed at reducing the psychological impact of trauma.
- Published
- 2018
41. Altered Oscillatory Responses to Feedback in Borderline Personality Disorder are Linked to Symptom Severity
- Author
-
Gregor Leicht, Christina Andreou, Christoph Mulert, Paul Alexander Schauer, and Jonas Rauh
- Subjects
Adult ,Male ,medicine.medical_specialty ,Neurology ,Feedback, Psychological ,Significant group ,Alpha (ethology) ,Audiology ,Electroencephalography ,Severity of Illness Index ,050105 experimental psychology ,Correlation ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Borderline Personality Disorder ,mental disorders ,Task Performance and Analysis ,medicine ,Humans ,0501 psychology and cognitive sciences ,Radiology, Nuclear Medicine and imaging ,Borderline personality disorder ,Positive feedback ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,business.industry ,05 social sciences ,Symptom severity ,medicine.disease ,Case-Control Studies ,Gambling ,Female ,Neurology (clinical) ,Anatomy ,business ,Beta Rhythm ,030217 neurology & neurosurgery - Abstract
Several studies using electroencephalography (EEG) demonstrate that the processing of feedback in patients suffering from borderline personality disorder (BPD) is altered in comparison to healthy controls. Differences occur in the theta (ca. 5 Hz) and high-beta frequency-ranges (ca. 20 Hz) of oscillations in response to negative and positive feedback, respectively. However, alpha (ca. 10 Hz) and low-beta (ca. 15 Hz) oscillations have also been shown to be involved in feedback processing. We hypothesized that additional alterations might occur in these frequency ranges in BPD. Eighteen patients with BPD and twenty-two healthy controls performed a gambling task while 64-channel-EEG was recorded. Induced oscillatory responses to positive (i.e. gain) and negative (i.e. loss) feedback in the alpha and low-beta frequency range were investigated. No significant differences were found in the alpha frequency range. Regarding the low-beta frequency range a significant Group (i.e. BPD vs. healthy controls) × Valence (i.e. gain vs. loss) interaction in the time frame between 600 and 700 milliseconds after feedback was found. This effect showed a significant correlation with symptom severity (assessed with the BSL-23). The results indicate that feedback processing in BPD could be more heavily altered than previously expected, with more severe symptomatology being linked to stronger alterations in oscillatory responses to feedback in the low-beta range.
- Published
- 2018
42. Investigation of sex differences in delusion-associated cognitive biases
- Author
-
Steffen Moritz, Ryan P. Balzan, Amatya Johanna Mackintosh, Christina Andreou, Chloé de Vos, Thies Lüdtke, and Letizia Leanza
- Subjects
Adult ,Male ,Decision Making ,Delusions ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Cognition ,Delusion ,Schizophrenic Psychology ,medicine ,Humans ,Young adult ,Biological Psychiatry ,Sex Characteristics ,business.industry ,Cognitive bias ,030227 psychiatry ,Psychiatry and Mental health ,Jumping to conclusions ,Female ,medicine.symptom ,business ,030217 neurology & neurosurgery ,Clinical psychology ,Sex characteristics ,Schizophrenia spectrum - Abstract
In the past few decades, sex differences have been identified in a number of clinical, cognitive and functional outcomes in patients with schizophrenia spectrum disorders. However, to date, sex differences in higher-order cognitive biases have not been systematically studied. The present study aimed to examine sex differences in jumping-to-conclusions and evidence integration impairment based on data collected in two previous studies in patients with schizophrenia spectrum disorders and healthy controls. For this purpose, data from n = 58 patients and n = 60 healthy controls on the Fish Task (as a measure of jumping to conclusions) and bias against disconfirmatory evidence (BADE; as a measure of evidence integration) task were analyzed. Results indicated a lack of sex differences in jumping-to-conclusions and evidence integration impairment both in patients with schizophrenia spectrum disorders and healthy controls. Although the present study was adequately powered to detect sex differences of a low medium effect size, larger studies are warranted to exclude differences of a smaller magnitude between men and women regarding delusion-associated cognitive biases.
- Published
- 2018
43. No associations between medial temporal lobe volumes and verbal learning/memory in emerging psychosis
- Author
-
Renata Smieskova, Fabienne Harrisberger, Stefan Borgwardt, Laura Egloff, Christina Andreou, Anita Riecher-Rössler, Ulrike Heitz, Letizia Leanza, Erich Studerus, André Schmidt, and Claudia Lenz
- Subjects
Adult ,Male ,medicine.medical_specialty ,Psychosis ,Hippocampus ,Grey matter ,Audiology ,Verbal learning ,Temporal lobe ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Cognition ,Memory ,medicine ,Humans ,Prospective Studies ,030304 developmental biology ,0303 health sciences ,California Verbal Learning Test ,business.industry ,General Neuroscience ,Organ Size ,Verbal Learning ,medicine.disease ,Magnetic Resonance Imaging ,Temporal Lobe ,medicine.anatomical_structure ,Psychotic Disorders ,Schizophrenia ,Female ,business ,Neurocognitive ,030217 neurology & neurosurgery - Abstract
Grey matter (GM) volume alterations have been repeatedly demonstrated in patients with first episode psychosis (FEP). Some of these neuroanatomical abnormalities are already evident in the at-risk mental state (ARMS) for psychosis. Not only GM alterations but also neurocognitive impairments predate the onset of frank psychosis with verbal learning and memory (VLM) being among the most impaired domains. Yet, their interconnection with alterations in GM volumes remains ambiguous. Thus, we evaluated associations of different subcortical GM volumes in the medial temporal lobe with VLM performance in antipsychotic-naive ARMS and FEP patients. Data from 59 ARMS and 31 FEP patients, collected within the prospective Fruherkennung von Psychosen study, were analysed. Structural T1-weighted images were acquired using a 3 Tesla magnetic resonance imaging scanner. VLM was assessed using the California Verbal Learning Test and its factors Attention Span, Learning Efficiency, Delayed Memory and Inaccurate Memory. FEP patients showed significantly enlarged volumes of hippocampus, pallidum, putamen and thalamus compared to ARMS patients. A significant negative association between amygdala and pallidum volume and Attention Span was found in ARMS and FEP patients combined, which however did not withstand correction for multiple testing. Although we found significant between-group differences in subcortical volumes and VLM is among the most impaired cognitive domains in emerging psychosis, we could not demonstrate an association between low performance and subcortical GM volumes alterations in antipsychotic-naive patients. Hence, deficits in this domain do not appear to stem from alterations in subcortical structures.
- Published
- 2018
44. Borderline Personality Disorder: Associations Between Dimensional Personality Profiles and Self-Destructive Behaviors
- Author
-
Steffen Moritz, Katharina Kolbeck, Julia Bierbrodt, and Christina Andreou
- Subjects
Agreeableness ,Adult ,Male ,050103 clinical psychology ,Adolescent ,media_common.quotation_subject ,Personality Disorders ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Borderline Personality Disorder ,mental disorders ,medicine ,Openness to experience ,Personality ,Humans ,0501 psychology and cognitive sciences ,Big Five personality traits ,Borderline personality disorder ,media_common ,Extraversion and introversion ,05 social sciences ,Conscientiousness ,Middle Aged ,medicine.disease ,Neuroticism ,030227 psychiatry ,Psychiatry and Mental health ,Clinical Psychology ,Female ,Self Report ,Psychology ,Self-Injurious Behavior ,Clinical psychology - Abstract
Ongoing research is shifting towards a dimensional understanding of borderline personality disorder (BPD). Aim of this study was to identify personality profiles in BPD that are predictive of self-destructive behaviors. Personality traits were assessed (n = 130) according to the five-factor model of personality (i.e., Neuroticism, Extraversion, Openness to Experience, Agreeableness, Conscientiousness) and an additional factor called Risk Preference. Self-destructive behavior parameters such as non-suicidal self-injury (NSSI) and other borderline typical dyscontrolled behaviors (e.g., drug abuse) were assessed by self-report measures. Canonical correlation analyses demonstrated that Neuroticism, Extraversion, and Conscientiousness are predictors of NSSI. Further, Neuroticism, Agreeableness, and Risk Preference were associated with dyscontrolled behaviors. Our results add further support on personality-relevant self-destructive behaviors in BPD. A combined diagnostic assessment could offer clinically meaningful insights about the causes of self-destruction in BPD to expand current therapeutic repertoires.
- Published
- 2018
45. The relationship between negative symptoms and cognitive functioning in patients at clinical high risk for psychosis
- Author
-
Letizia Leanza, Laura Egloff, Christina Andreou, Erich Studerus, Martina Uttinger, Anita Riecher-Rössler, Sarah Ittig, Katharina Beck, and Ulrike Heitz
- Subjects
Adult ,Male ,Psychosis ,Alogia ,Asociality ,Neuropsychological Tests ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Cognition ,Risk Factors ,medicine ,Verbal fluency test ,Humans ,Prospective Studies ,Scale for the Assessment of Negative Symptoms ,Biological Psychiatry ,medicine.diagnostic_test ,business.industry ,Anhedonia ,Neuropsychological test ,medicine.disease ,030227 psychiatry ,Psychiatry and Mental health ,Cross-Sectional Studies ,Psychotic Disorders ,Female ,medicine.symptom ,business ,Cognition Disorders ,Neurocognitive ,030217 neurology & neurosurgery ,Clinical psychology - Abstract
Negative symptoms and neurocognitive performance have been reported to be negatively associated in patients with emerging psychosis. However, most previous studies focused on patients with frank psychosis and did not differentiate between subdomains of negative symptoms. Hence, we aimed to elucidate the specific relationship between negative symptoms and cognitive functioning in patients at clinical high risk (CHR) for psychosis. Data from 154 CHR patients collected within the prospective Fruherkennung von Psychosen (FePsy) study were analyzed. Negative symptoms were assessed with the Scale for the Assessment of Negative Symptoms (SANS) and cognitive functioning with an extensive neuropsychological test battery. Regression analyses revealed significant negative associations between negative symptoms and cognitive functioning, particularly in the domains of nonverbal intelligence and verbal fluency. When analyzing each negative symptom domain separately, alogia and asociality/anhedonia were significantly negatively associated with nonverbal intelligence and alogia additionally with verbal fluency. Overall, our results in CHR patients are similar to those reported in patients with frank psychosis. The strong negative association between verbal fluency and negative symptoms may be indicative of an overlap between these constructs. Verbal fluency might have a strong influence on the clinical impression of negative symptoms (particularly alogia) and vice versa.
- Published
- 2018
- Full Text
- View/download PDF
46. Evaluating verbal learning and memory in patients with an at-risk mental state or first episode psychosis using structural equation modelling
- Author
-
Katharina Beck, Ronan Zimmermann, Laura Egloff, Christina Andreou, Sarah Ittig, Anita Riecher-Rössler, Ulrike Heitz, Erich Studerus, Stefan Borgwardt, and S. Menghini-Müller
- Subjects
Male ,Social Sciences ,lcsh:Medicine ,Audiology ,Learning and Memory ,Cognition ,0302 clinical medicine ,Medicine and Health Sciences ,Psychology ,Antipsychotics ,Prospective Studies ,lcsh:Science ,Cognitive Impairment ,First episode ,Multidisciplinary ,California Verbal Learning Test ,Cognitive Neurology ,Drugs ,Verbal Learning ,Neurology ,Female ,Research Article ,Adult ,Learning Curves ,Psychosis ,medicine.medical_specialty ,Cognitive Neuroscience ,education ,Models, Psychological ,Verbal learning ,Attention span ,03 medical and health sciences ,Memory ,Neuropsychology ,Mental Health and Psychiatry ,medicine ,Learning ,Humans ,Neuropsychological Testing ,Pharmacology ,Recall ,lcsh:R ,Cognitive Psychology ,Psychoses ,Biology and Life Sciences ,At risk mental state ,medicine.disease ,030227 psychiatry ,Psychotic Disorders ,Learning curve ,Mental Recall ,Cognitive Science ,lcsh:Q ,030217 neurology & neurosurgery ,Neuroscience - Abstract
Background Verbal learning and memory are impaired not only in patients with a first episode of psychosis (FEP) but also–to a lower extent–in those with an at-risk mental state for psychosis (ARMS). However, little is known about the specific nature of these impairments. Hence, we aimed to study learning and memory processes in ARMS and FEP patients by making use of structural equation modelling. Methods Verbal learning was assessed with the California Verbal Learning Test (CVLT) in 98 FEP patients, 126 ARMS patients and 68 healthy controls (HC) as part of the Basel early detection of psychosis (FePsy) study. The four-factorial CFA model of Donders was used to estimate test performance on latent variables of the CVLT and growth curve analysis was used to model the learning curve. The latter allows disentangling initial recall, which is strongly determined by attentional processes, from the learning rate. Results The CFA model revealed that ARMS and FEP patients were impaired in Attention Span, Learning Efficiency and Delayed Memory and that FEP patients were additionally impaired in Inaccurate Memory. Additionally, ARMS-NT, but not ARMS-T, performed significantly worse than HC on Learning Efficiency. The growth curve model indicated that FEP patients were impaired in both initial recall and learning rate and that ARMS patients were only impaired in the learning rate. Conclusions Since impairments were more pronounced in the learning rate than the initial recall, our results suggest that the lower scores in the CVLT reported in previous studies are more strongly driven by impairments in the rate of learning than by attentional processes.
- Published
- 2018
- Full Text
- View/download PDF
47. Dopamine effects on evidence gathering and integration
- Author
-
Katharina Kolbeck, Christina Andreou, Jürgen Gallinat, Vivien Braun, Brooke C. Schneider, and Steffen Moritz
- Subjects
Adult ,Male ,Agonist ,Levodopa ,Adolescent ,medicine.drug_class ,Dopamine ,medicine.medical_treatment ,Decision Making ,Dopamine Agents ,Neuropsychological Tests ,law.invention ,Young Adult ,Double-Blind Method ,Randomized controlled trial ,law ,medicine ,Haloperidol ,Humans ,Pharmacology (medical) ,Antipsychotic ,Problem Solving ,Biological Psychiatry ,Cross-Over Studies ,business.industry ,Dopaminergic ,Antagonist ,Psychiatry and Mental health ,Linear Models ,Female ,business ,Neuroscience ,Research Paper ,medicine.drug - Abstract
Disturbances in evidence gathering and disconfirmatory evidence integration have been associated with the presence of or propensity for delusions. Previous evidence suggests that these 2 types of reasoning bias might be differentially affected by antipsychotic medication. We aimed to investigate the effects of a dopaminergic agonist (L-dopa) and a dopaminergic antagonist (haloperidol) on evidence gathering and disconfirmatory evidence integration after single-dose administration in healthy individuals.The study used a randomized, double-blind, placebo-controlled, 3-way crossover design. Participants were healthy individuals aged 18-40 years. We administered a new data-gathering task designed to increase sensitivity to change compared with traditional tasks. The Bias Against Disconfirmatory Evidence (BADE) task was used as a measure of disconfirmatory evidence integration.We included 30 individuals in our study. In the data-gathering task, dopaminergic modulation had no significant effect on the amount of evidence gathered before reaching a decision. In contrast, the ability of participants to integrate disconfirmatory evidence showed a significant linear dopaminergic modulation pattern (highest with haloperidol, intermediate with placebo, lowest with L-dopa), with the difference between haloperidol and L-dopa marginally reaching significance.Although the doses used for haloperidol and L-dopa were similar to those used in previous studies, drug plasma level measurements would have added to the validity of findings.Evidence gathering and disconfirmatory evidence integration might be differentially influenced by dopaminergic agents. Our findings are in support of a dual-disturbance account of delusions and provide a plausible neurobiological basis for the use of interventions targeted at improving reasoning biases as an adjunctive treatment in patients with psychotic disorders.
- Published
- 2015
48. The role of obsessive-compulsive symptoms in the perception of insincere speech in first-episode psychosis
- Author
-
George Garyfallos, Evangelos Ntouros, Christina Andreou, Ekaterini Tsoura, Vasilis P. Bozikas, George Floros, and Elena-Ioanna Nazlidou
- Subjects
Adult ,Male ,Obsessive-Compulsive Disorder ,Psychosis ,medicine.medical_specialty ,Speech perception ,media_common.quotation_subject ,Neuropsychological Tests ,Statistics, Nonparametric ,Young Adult ,Perception ,medicine ,Humans ,Young adult ,Psychiatry ,media_common ,Psychiatric Status Rating Scales ,Sarcasm ,Positive and Negative Syndrome Scale ,Social perception ,Age Factors ,medicine.disease ,Comorbidity ,Clinical Psychology ,Psychotic Disorders ,Social Perception ,Neurology ,Speech Perception ,Regression Analysis ,Female ,Neurology (clinical) ,Psychology - Abstract
The aim of the present study was to investigate the effects of comorbid obsessive-compulsive symptoms (OCS) on the perception of insincere speech (e.g., sarcasm and white lies) in patients with first-episode psychosis.Participants were 65 patients with nonaffective first-episode psychosis (FEP) and 47 healthy controls. The patient group was divided into two subgroups, those with (FEP+; n= 38) and those without OCS (FEP-; n = 27). The ability to process sarcasm and lie was assessed with the Perception of Social Inference Test (PESIT). Severity of psychotic symptoms and OCS was assessed with the Positive and Negative Syndrome Scale (PANSS) and the Yale-Brown Obsessive Compulsive Scale (Y-BOCS), respectively.Deficits in the perception of sarcasm and lie were confirmed in patients with nonaffective first-episode psychosis compared to healthy controls. In patients, comorbidity with OCS was associated with worse performance on certain aspects of insincere speech (i.e., lie) compared to FEP- patients. Y-BOCS scores correlated significantly with the perception of lying. The cognitive factor of the PANSS predicted accuracy on the perception of sincere speech, paradoxical sarcasm, and white lies, while the presence of OCS predicted accuracy on the perception of sincere speech and white lies.Our finding of impaired counterfactual information processing in patients with first-episode psychosis suggests that these deficits are already present at illness onset. Presence of OCS appears to have additional deleterious effects on the successful interpretation of intentional lying, further supporting that these patients are characterized by more extensive cognitive impairment.
- Published
- 2015
49. The Benefits of Doubt: Cognitive Bias Correction Reduces Hasty Decision-Making in Schizophrenia
- Author
-
Nora Ramdani, Christina Andreou, Lisa Endlich, Helena Mayer-Stassfurth, Steffen Moritz, Franz Petermann, and Ryan P. Balzan
- Subjects
Psychosis ,Intention-to-treat analysis ,Neuropsychology ,Experimental and Cognitive Psychology ,Cognition ,medicine.disease ,Cognitive bias ,Checklist ,Clinical Psychology ,Schizophrenia ,medicine ,Paranoia ,medicine.symptom ,Psychology ,Clinical psychology - Abstract
Many patients with schizophrenia display neuropsychological deficits in concert with cognitive biases, particularly the tendency to jump to conclusions (JTC). The present study examined the effects of a generic psychoeducational cognitive bias correction (CBC) program. We hypothesized that demonstrating the fallibility of human cognition to patients would diminish their susceptibility to the JTC bias. A total of 70 participants with schizophrenia were recruited online. At baseline, patients were asked to fill out a JTC task (primary outcome) and the Paranoia Checklist before being randomized to either the CBC or a waitlist control condition. The CBC group received six successive pdf-converted PowerPoint presentations teaching them about cognitive biases; we neither placed any emphasis on psychosis-related cognitive distortions nor addressed psychosis. Six weeks after inclusion, subjects were re-administered the JTC task and the Paranoia Checklist. At a medium-to-large effect size the JTC bias was significantly improved under the CBC condition in comparison to controls for both the per protocol and the intention to treat analysis. The Paranoia Checklist remained essentially unchanged over time. No effects were observed for depression. Psychoeducational and cognitive programs are urgently needed as many patients are still deprived of any psychological treatment despite recommendations of most guidelines. Self-help may bridge the large treatment gap in schizophrenia and motivate patients to seek help. The study asserts both the feasibility and effectiveness of self-help programs in schizophrenia.
- Published
- 2015
50. Neurocognitive deficits are relevant for the jumping-to-conclusions bias, but not for delusions: A longitudinal study
- Author
-
Daniela Roesch-Ely, Daniel Luedecke, Christina Andreou, Steffen Moritz, Ryan P. Balzan, and Brooke C. Schneider
- Subjects
Longitudinal study ,medicine.medical_specialty ,Cognitive Neuroscience ,Metacognitive training ,medicine.disease ,Cognitive bias ,lcsh:RC346-429 ,Article ,Delusions ,Cognitive biases ,Psychiatry and Mental health ,Delusion ,Schizophrenia ,Cognitive remediation therapy ,Jumping to conclusions ,medicine ,Cognitive remediation ,Cognitive skill ,medicine.symptom ,Psychology ,Psychiatry ,Neurocognitive ,lcsh:Neurology. Diseases of the nervous system - Abstract
Patients with delusions exhibit an increased tendency to arrive at decisions based on very limited evidence (jumping-to-conclusions; JTC), making this reasoning bias relevant for the treatment of delusions. Neurocognitive deficits contribute to JTC, but it is not known whether this has any bearing on the clinical syndrome of delusions. We addressed this question by reanalyzing data from an efficacy study of non-pharmacological interventions as adjunctive treatments in schizophrenia. We investigated the longitudinal associations of cognitive functioning, JTC and delusions in patients with psychotic disorders receiving either a metacognitive intervention addressing reasoning biases (n=59), or cognitive remediation (n=58). Both interventions improved JTC; in the cognitive remediation group, tentative evidence suggested that better neurocognitive performance contributed to this improvement. However, JTC gains were associated with delusion improvement only in the metacognitive intervention group, suggesting a content-specific mechanism of action.
- Published
- 2015
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.