Search

IntroductionDespite innovative treatments, the impairment in real-life functioning in subjects with schizophrenia (SCZ) remains an unmet need in the care of these patients. Recently, real-life functioning in SCZ was associated with abnormalities in different electrophysiological indices. It is still not clear whether this relationship is mediated by other variables, and how the combination of different EEG abnormalities influences the complex outcome of schizophrenia.ObjectivesThe purpose of the study was to find EEG patterns which can predict the outcome of schizophrenia and identify recovered patients.MethodsIllness-related and functioning-related variables were measured in 61 SCZ at baseline and after four-years follow-up. EEGs were recorded at the baseline in resting-state condition and during two auditory tasks. We performed Sparse Partial Least Square (SPLS) Regression, using EEG features, age and illness duration to predict clinical and functional features at baseline and follow up. Through a Linear Support Vector Machine (Linear SVM) we used electrophysiological and clinical scores derived from SPLS regression, in order to classify recovered patients at follow-up.ResultsWe found one significant latent variable (pConclusionsA combination of electrophysiological markers, age and illness-duration might predict clinical and functional outcome of schizophrenia after 4 years of follow-up.

IntroductionDifferent electrophysiological indices have been investigated to identify diagnostic and prognostic markers of schizophrenia (SCZ). However, these indices have limited use in clinical practice, since both specificity and association with illness outcome remain unclear. In recent years, machine learning techniques, through the combination of multidimensional data, have been used to better characterize SCZ and to predict illness course.ObjectivesThe aim of the present study is to identify multimodal electrophysiological biomarkers that could be used in clinical practice in order to improve precision in diagnosis and prognosis of SCZ.MethodsIllness-related and functioning-related variables were measured at baseline in 113 subjects with SCZ and 57 healthy controls (HC), and after four-year follow-up in 61 SCZ. EEGs were recorded at baseline in resting-state condition and during two auditory tasks (MMN-P3a and N100-P3b). Through a Linear Support Vector Machine, using EEG data as predictors, four models were generated in order to classify SCZ and HC. Then, we combined unimodal classifiers’ scores through a stacking procedure. Pearson’s correlations between classifiers score with illness-related and functioning-related variables, at baseline and follow-up, were performed.ResultsEach EEG model produced significant classification (p < 0.05). Global classifier discriminated SCZ from HC with accuracy of 75.4% (p < 0.01). A significant correlation (r=0.40, p=0.002) between the global classifier scores with negative symptoms at follow-up was found. Within negative symptoms, blunted affect showed the strongest correlation.ConclusionsAbnormalities in electrophysiological indices might be considered trait markers of schizophrenia. Our results suggest that multimodal electrophysiological markers might have prognostic value for negative symptoms.

IntroductionIn subjects with schizophrenia (SCZ), the disorganization factor was found to be a strong predictor of real-life functioning. “Conceptual disorganization” (P2), “difficulties in abstract thinking” (N5) and “poor attention” (G11) are considered core aspects of the disorganization factor, as assessed by PANSS. The overlap of these items with neurocognitive functions is debated and should be further investigated.AimsWithin the Italian network for research on psychoses study, electrophysiological and neurocognitive correlates of the disorganization factor and its component items were investigated.MethodsResting state EEGs were recorded in 145 stabilized SCZ and 69 matched healthy controls (HC). Spectral amplitude (SAmp) was averaged in nine frequency bands. MATRICS consensus cognitive battery (MCCB) was used for neurocognitive assessment. Band SAmp differences and correlations with psychopathology and MCCB scores were explored by global randomization statistics.ResultsSCZ showed increased delta, theta, and beta1 and decreased alpha2 SAmp. A negative correlation between alpha1 and disorganization was observed in SCZ. At the item level, only N5 showed this correlation. MCCB neurocognitive composite was associated with P2 and N5 but not with alpha1 SAmp.ConclusionsOur findings suggest an heterogeneity of the disorganization dimension and a partial overlap with neurocognitive domains. The N5, “difficulties in abstract thinking”, had a unique association with alpha1 SAmp, which is thought to be involved in the formation of conceptual maps.Disclosure of interestThe authors have not supplied their declaration of competing interest.

BackgroundIncreasing body of evidence suggest that patients with schizophrenia (SCZ) present dysfunction of the gamma band oscillations (GBO) during cognitive tasks. The current study aimed to explore the GBO activity in SCZ during a Sternberg task.Materials and methodsTwenty-eight chronic stabilized SCZ and 18 healthy controls (HC), were recruited. Ongoing EEG was recorded during the execution of the Sternberg task. Continuous EEG data were band-pass filtered (1–100 Hz) and corrected for eye blink and muscle artefacts by ICA. For each subject, the event-related-spectral-perturbation (ERSP) and the inter-trial-coherence (ITC) were computed at the Pz channel only for those stimulus-locked segments containing correct responses. GBO wavelet analysis was performed with two different increasing cycle ranges (3 to 5.8 and 12 to 22.6; frequency range: 30–90 Hz), to obtain the best information about temporal and frequency dynamics. Student's t test (with multiple comparisons FDR correction) was used to compare the groups.ResultsDuring the manteinance phase (4000 to 4600 ms after the stimulus onset), SCZ presented a significant increase, respect to HC, in low GBO activity (range: 30-50 Hz;). In the other phases of the Sternberg task (encoding, probe presentation and response periods), no significant difference in GBO was observed between SCZ and HC.ConclusionsThese findings are in line with the evidence that GBO dysfunction in SCZ is present during selective phases of the working memory task. Future studies have to clarify the role of GBO dysfunction on the cognitive performance and the clinical utility of selective GBO modulation during cognitive rehabilitation.Disclosure of interestThe authors have not supplied their declaration of competing interest.

BackgroundIt is hypothesized that the event-related potentials are generated by different electrophysiological mechanisms, i.e., event-related power increase and enhanced degree of phase-locking over trial. The study aimed to characterize the relative contribution of these mechanisms to the ERP in patients with schizophrenia (SCZ).Materials and methodsOne hundred and fifteen chronic stabilized SCZ and 62 healthy controls (HC) recruited to the study of the Italian Network for Research on Psychoses were included. Scalp potentials were recorded during a standard auditory oddball task. Stimulus-locked segments were extracted for all standard trials and correctly hit target trials. Trials contaminated by other artifacts were rejected. For each subject and stimulus type the event-related spectral perturbation (ERSP) and the inter-trial-coherence (ITC) were computed to assess event-related power increase and inter-trial phase-locking. The two groups were compared using Student's t-test followed by Bonferroni correction for multiple comparisons.ResultsSCZ presented a reduced amplitude of both N100 and P3b. For both standard and target stimuli, at Cz and Pz, ERSP was reduced in SCZ in the delta-theta band (from 0 up to 400 ms). The ITC index, at the same channels, was reduced in SCZ in the delta band for standard stimuli (from 0 to 300 ms), and in both delta and theta bands for target stimuli (from 300 to 400 ms).ConclusionsOur results indicate that alterations of both mechanisms are involved in N100 and P3b amplitude reduction observed in SCZ. Inter-trial phase-locking abnormalities for N100 were limited to the delta band, while for P3b involved delta and theta frequencies.Disclosure of interestThe authors have not supplied their declaration of competing interest.

IntroductionNeural dysconnectivity is hypothesized to be a key element in pathophysiology of schizophrenia. However, the relation of disordered connectivity with the different clinical characteristics of the syndrome is not fully elucidated.ObjectivesThe current research investigated the relations between resting-state EEG Source Functional Connectivity (EEG-SFC) and the two main clusters of negative symptoms derived from the Brief Negative Symptom Scale, the Expressive Deficit (ED) and the Avolition (AV), in subjects with schizophrenia (SCZ) enrolled to the multicentre study of the Italian Network for Research on Psychoses.MethodsOut of 97 chronic, stabilized SCZ included, we selected subjects according the lower and the upper quartile of the ED and AV value distribution: 25 were in upper and 24 in the lower quartile of ED (respectively, HIGH-ED and LOW-ED); 27 were in upper and 24 in the lower quartile of AV (respectively, HIGH-AV and LOW-AV). Fifty-five healthy controls (HC) were included, comparable to SCZ for gender, age and educational level. EEG-SFC analysis was based on the lagged phase synchronization (LPS) computed by eLORETA from 5 minutes resting-state EEG recordings in eyes closed condition. LPS indices were determined for each spectrum band and between all 28 regions of interest (ROI) pairs. Group differences were significant for corrected P-value < 0.05.ResultsSCZ had higher theta band LPS than HC. Respect to LOW-ED, HIGH-ED showed significant increased alpha LPS in fronto-cingulate, para-hippocampal and insular inter-hemispheric ROI pairs. No significant difference emerged between HIGH-AV and LOW-AV.ConclusionsSubgrouping SCZ according to negative symptom severity reveals heterogeneous patterns of resting-state LPS connectivity.Disclosure of interestThe authors have not supplied their declaration of competing interest.

IntroductionNegative symptoms have long been recognized as a central feature of schizophrenia, which limit recovery, having a strong negative impact on real-life functioning. External validators of the negative symptoms domains might help refining hypotheses on their pathophysiological basis.AimsThe objective of this study was to evaluate, in the context of the multicenter study of the Italian Network for Research on Psychoses, the relationships between auditory event-related potentials (ERPs) components and negative symptom domains in patients with schizophrenia (SCZ).MethodsWe examined ERPs recorded during an auditory odd-ball task in 115 chronic stabilized SCZ (78% on second-generation antipsychotics) and 62 matched healthy controls (HC). Negative symptoms were assessed using the Brief Negative Symptom Scale.ResultsOur main findings included significant N100 and P3b amplitude reductions in SCZ compared to HC. P3b amplitude did not correlate with any negative symptom domain, while N100 amplitude correlated with both anhedonia and avolition domains.ConclusionsAvolition and anhedonia, often clustering in the same factor, are related to abnormalities of early components of the ERPs correlated with perceptual and automatic attention processes. None of the negative symptom domains is associated with abnormalities of the later stages indexed by P3 amplitude.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Objectives Asylum Seekers (AS) often experience stressful situations that may lead to psychiatric disorders. Our hypothesis is that the subjective perception of stressors and the resulting psychiatric symptoms may depend on the length of staying, length of the journey, level of education and age. Methods 45 AS, guests of a reception center in Borgo Mezzanone (Foggia, Italy), were assessed by means of: Addiction Severity Index, MINI, SCL-90-R and Davidson Trauma Scale (DTS). We investigated the length of the voyage and the number of nations they passed through before reaching the final destination. Results 35,6% of the patients reported PTSD, 75,6% current Major Depressive Episode, 90,5% GAD, 2,3% psychotic symptoms, 15,6% alcohol abuse and 11,1% cannabis abuse; moreover, 26,7% attempted suicide at least once. Younger ones were less concerned about physical health and scored higher at most of SCL-90-R subscales. People who have been migrated for less time are more worried about family members left home and have higher scores at DTS subscales intrusion (p=0,02), hyperarousal, frequency, as well as total score. The number of nations they passed through or stayed in during their journey, negatively correlates with DTS hyperarousal and total gravity scores. Migrants with higher education showed lower scores in SCL somatization subscale. Conclusions younger people seems to have more severe psychiatric symptoms despite minor concerns about health and it seems that concerns about family members and various PTSD symptoms tend to decrease with time. Moreover a higher level of education may be protective from the tendency to somatize.

Objectives Asylum Seekers experience different kinds of trauma, such as tortures, threats and loss of family members in the countries of origin, but also desperate journeys and legal concerns in the accepting countries. Our aim is to investigate mental health disorders among AS and to study the importance of torture in the development of their symptoms. Methods We recruited 45 AS (males, age 29±6), guests of a reception center in Borgo Mezzanone (Foggia, Italy). The following instruments were administered: MINI, SCL-90-R and Davidson Trauma Scale (DTS). Pre-migration, migration, and post-migration stressors were assessed using a self-administered scale. Results 75,6% of our patients reported a Major Depressive Episode currently, while 20% in the past. 35,6% suffered from PTSD, 13,3% agoraphobia. and 88,9% GAD. 2,3% reported psychotic symptoms and 13,3% alcohol or drugs abuse in the last year. Torture showed a correlation with PTSD (p Conclusions most of AS showed depressive and anxious symptoms and one-third had PTSD. All of them experienced different kinds of traumas, but only torture seems to play a major role in developing PTSD, while all kinds of trauma are equally important as to the perceived symptomatology, since both torture and PTSD did not correlate with higher SCL-90-R scores.