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Children with neurofibromatosis type 1 (NF1) often experience executive dysfunction, attention deficit/hyperactivity disorder (ADHD) symptoms and poor social skills, however, the nature of the relationships between these domains in children with NF1 is unclear. This study investigated these relationships using primary caregiver ratings of executive functions, ADHD symptoms and social skills in children with NF1. Participants were 136 children with NF1 and 93 typically developing (TD) controls aged 3-15 years recruited from 3 multidisciplinary neurofibromatosis clinics in Melbourne and Sydney, Australia, and Washington DC, USA. Mediation analysis was performed on primary outcome variables: parent ratings of executive functions (Behavior Rating Inventory of Executive Function, Metacognition Index), ADHD symptoms (Conners-3/Conners ADHD Diagnostic and Statistical Manual for Mental Disorders Scales) and social skills (Social Skills Improvement System-Rating Scale), adjusting for potential confounders (full scale IQ, sex, and social risk). Results revealed significantly poorer executive functions, elevated ADHD symptoms and reduced social skills in children with NF1 compared to controls. Poorer executive functions significantly predicted elevated ADHD symptoms and poorer social skills. Elevated ADHD symptoms significantly mediated the relationship between executive functions and social skills problems although did not fully account for social dysfunction. This study provides evidence for the importance of targeting ADHD symptoms as part of future interventions aimed at promoting prosocial behaviors in children with NF1.

Background: The COVID 19 pandemic has created unprecedented acute global health challenges. However, it also presents a set of unquantified and poorly understood risks in the medium to long term, specifically, risks to children whose mothers were infected with the SARS-CoV-2 virus during pregnancy. Methods: We have designed a prospective, case-controlled study to investigate the long-term impacts of SARS-CoV2 exposure on children exposed in utero. Women infected with SARS-CoV-2 during pregnancy will be recruited from Monash Health, the Royal Women’s Hospital and Western Health (Melbourne, Australia) and Londrina Municipal Maternity Hospital Lucilla Ballalai and PUCPR Medical Clinical (Londrina, Brazil). A control group in a 2:1 ratio (2 non-exposed: 1 exposed mother infant dyad) comprising women who gave birth in the same month of delivery, are of similar age but did not contract SARS-CoV-2 during their pregnancy will also be recruited. We aim to recruit 150 exposed and 300 non-exposed mother-infant dyads. Clinical and socio-demographic data will be collected directly from the mother and medical records. Biospecimens and clinical and epidemiological data will be collected from the mothers and offspring at multiple time points from birth through to 15 years of age using standardised sample collection, and neurological and behavioural measures. Discussion: The mapped neurodevelopmental trajectories and comparisons between SARS-CoV2 exposed and control children will indicate the potential for an increase in atypical neurodevelopment. This has significant implications for strategic planning in the mental health and paediatrics sectors and long-term monitoring of children globally.

This study investigated sex and age differences in autistic behaviours in children with neurofibromatosis type 1 (NF1) who scored within the clinical range on the Social Responsiveness Scale - Second Edition (T score ≥ 60). Thirty-four males and 28 females (3-16 years) were assessed with the Autism Diagnostic Observation Schedule - Second Edition and Autism Diagnostic Interview - Revised. Across both measures, males exhibited greater social communication deficits relative to females. Age-related abatement of social communication difficulties was observed for males but not females. Conversely, no sex differences were found for restricted/repetitive behaviours, which were stable over time for both males and females. The findings are discussed within the context of broader neurodevelopmental considerations that are common in NF1.

BackgroundThe ability to generate a precise internal model of statistical regularities is impaired in schizophrenia. Predictive coding accounts of schizophrenia suggest that psychotic symptoms may be explained by a failure to build precise beliefs or a model of the world. The precision of this model may vary with context. For example, in a noisy environment the model will be more imprecise compared to a model built in an environment with lower noise. However compelling, this idea has not yet been empirically studied in schizophrenia. Methods: In this study, 62 participants engaged in a stochastic mismatch negativity paradigm with high and low precision. We included inpatients with a schizophrenia spectrum disorder (N=20), inpatients with a psychiatric disorder but without psychosis (N=20), and healthy controls (N=22), with comparable sex ratio and age distribution. Bayesian mapping and dynamic causal modelling were employed to investigate the underlying microcircuitry of precision encoding of auditory stimuli. Results: We found strong evidence (exceedance p > 0.99) for differences in the underlying connectivity associated with precision encoding between the three groups as well as on the continuum of psychotic-like experiences assessed across all participants. Critically, we show changes in interhemispheric connectivity between the two inpatient groups, with some connections further aligning on the continuum of psychotic-like experiences. Conclusions: While our results suggest continuity in backward connectivity alterations with psychotic-like experiences regardless of diagnosis, they also point to specificity for the schizophrenia spectrum disorder group in interhemispheric connectivity alterations.

This study investigated sex and age differences in autistic behaviours in children with neurofibromatosis type 1 (NF1) who scored within the clinical range on the Social Responsiveness Scale - Second Edition (T score ≥ 60). Thirty-four males and 28 females (3–16 years) were assessed with the Autism Diagnostic Observation Schedule - Second Edition and Autism Diagnostic Interview - Revised. Across both measures, males exhibited greater social communication deficits relative to females. Age-related abatement of social communication difficulties was observed for males but not females. Conversely, no sex differences were found for restricted/repetitive behaviours, which were stable over time for both males and females. The findings are discussed within the context of broader neurodevelopmental considerations that are common in NF1.

Recent theories in computational psychiatry propose that unusual perceptual experiences and delusional beliefs may emerge as a consequence of aberrant inference and disruptions in sensory learning. The current study investigates these theories and examines the alterations that are specific to schizophrenia spectrum disorders vs those that occur as psychotic phenomena intensify, regardless of diagnosis. We recruited 66 participants: 22 schizophrenia spectrum inpatients, 22 nonpsychotic inpatients, and 22 nonclinical controls. Participants completed the reversal oddball task with volatility manipulated. We recorded neural responses with electroencephalography and measured behavioral errors to inferences on sound probabilities. Furthermore, we explored neural dynamics using dynamic causal modeling (DCM). Attenuated prediction errors (PEs) were specifically observed in the schizophrenia spectrum, with reductions in mismatch negativity in stable, and P300 in volatile, contexts. Conversely, aberrations in connectivity were observed across all participants as psychotic phenomena increased. DCM revealed that impaired sensory learning behavior was associated with decreased intrinsic connectivity in the left primary auditory cortex and right inferior frontal gyrus (IFG); connectivity in the latter was also reduced with greater severity of psychotic experiences. Moreover, people who experienced more hallucinations and psychotic-like symptoms had decreased bottom-up and increased top-down frontotemporal connectivity, respectively. The findings provide evidence that reduced PEs are specific to the schizophrenia spectrum, but deficits in brain connectivity are aligned on the psychosis continuum. Along the continuum, psychotic experiences were related to an aberrant interplay between top-down, bottom-up, and intrinsic connectivity in the IFG during sensory uncertainty. These findings provide novel insights into psychosis neurocomputational pathophysiology.

Impairments in social cognition—including recognition of facial expressions—are increasingly recognised as a core deficit in schizophrenia. It remains unclear whether other aspects of face processing (such as identity recognition) are also impaired, and whether such deficits can be attributed to more general cognitive difficulties. Moreover, while the majority of past studies have used picture-based tasks to assess face recognition, literature suggests that video-based tasks elicit different neural activations and have greater ecological validity. This study aimed to characterise face processing using video-based stimuli in psychiatric inpatients with and without psychosis. Symptom correlates of face processing impairments were also examined. Eighty-six psychiatric inpatients and twenty healthy controls completed a series of tasks using video-based stimuli. These included two emotion recognition tasks, two non-emotional facial identity recognition tasks, and a non-face control task. Symptoms were assessed using the Positive and Negative Syndrome Scale. Schizophrenia and bipolar disorder groups were significantly impaired on the emotion-processing tasks and the non-face task compared to healthy controls and patients without psychosis. Patients with other forms of psychosis performed intermediately. Groups did not differ in non-emotional face processing. Positive symptoms of psychosis correlated directly with both emotion-processing performance and non-face discrimination across patients. We found that identity processing performance was inversely associated with cognition-related symptoms only. Findings suggest that deficits in emotion-processing reflect symptom pathology independent of diagnosis. Emotion-processing deficits in schizophrenia may be better accounted for by task-relevant factors—such as attention—that are not specific to emotion processing.

Despite their widespread use, typical visual observation practices are not evidence-based and adverse events - such as self-harm and absconding - still occur even under the most intense forms of observation. This study aimed to (i) develop and implement an engagement-focused systematized model of clinical risk management in an adult acute psychiatric inpatient unit; and (ii) prospectively evaluate its effect on rates of violence, self-harm, absconding, sexually inappropriate behaviour, and seclusion. A new model of engagement-focused clinical risk management was developed using a participatory action research framework and implemented in an adult acute psychiatric inpatient unit. Using a mirror-image design, rates of violence/aggression, self-harm, absconding, sexually inappropriate behaviour, and seclusion were compared before and after implementation, and staff satisfaction levels were measured. The clinical engagement-based model was introduced, and 1087 admissions before implementation (24 months) were compared with 965 admissions post-implementation (18 months). The new model was associated with significantly reduced rates of absconding (pre: 10.5/1000 occupied bed days, 95% CI [9.0, 12.1] compared with post: 6.5/1000 occupied bed days [5.2, 8.1], P

Face-based tasks are used ubiquitously in the study of human perception and cognition. Video-based (dynamic) face stimuli are increasingly utilized by researchers because they have higher ecological validity than static images. However, there are few ready-to-use dynamic stimulus sets currently available to researchers that include non-emotional and non-face control stimuli. This paper outlines the development of three original dynamic stimulus sets: a set of emotional faces (fear and disgust), a set of non-emotional faces, and a set of car animations. Morphing software was employed to vary the intensity of the expression shown and to vary the similarity between actors. Manipulating these dimensions permits us to create tasks of varying difficulty that can be optimized to detect more subtle differences in face-processing ability. Using these new stimuli, two preliminary experiments were conducted to evaluate different aspects of facial identity recognition, emotion recognition, and non-face object discrimination. Results suggest that these five different tasks successfully avoided floor and ceiling effects in a healthy sample. A second experiment found that dynamic versions of the emotional stimuli were recognized more accurately than static versions, both for labeling, and discrimination paradigms. This indicates that, like previous emotion-only stimuli sets, the use of dynamic stimuli confers an advantage over image-based stimuli. These stimuli therefore provide a useful resource for researchers looking to investigate both emotional and non-emotional face-processing using dynamic stimuli. Moreover, these stimuli vary across crucial dimensions (i.e., face similarity and intensity of emotion) which allows researchers to modify task difficulty as required.

BACKGROUND: Recent theories in computational psychiatry have proposed that unusual perceptual experiences and delusional beliefs in psychotic disorders may emerge as a consequence of aberrant inference and disruptions in prediction error updating. The current study investigates anomalies in belief formation and updating that are specific to the schizophrenia spectrum. Furthermore, we examine psychosis as a continuum, which extends into the non-clinical population, and investigate anomalies that align on the continuum of psychosis. We characterised the underlying neural dynamics of impaired belief formation, or ‘regularity learning’ in stable and volatile contexts. METHODS: 66 participants (22 inpatients with a schizophrenia spectrum disorder (SZS), 22 non-psychotic inpatients (NP), and 22 non-clinical controls (NC)) completed an auditory oddball task with volatility manipulated. The psychosis continuum in our sample was measured using the Community Assessment of Psychic Experience Questionnaire. We recorded prediction error responses with electroencephalography and behaviorally measured regularity learning errors to inferences on the probability of sounds presented within stable and volatile contexts. Furthermore, we explored how the neural dynamics relate to psychotic experiences using Dynamic Causal Modelling. RESULTS: Attenuated prediction error responses were specifically observed in the SZS but not in NP group, with reductions in mismatch negativity (MMN) in stable, and P300 in volatile contexts. Attenuation in P300 was related to poorer regularity learning and psychotic experiences across the whole sample. Whole-brain source reconstruction showed decreased activity for P300 prediction errors in SZS compared to NC in the medial frontal gyrus, insula and primary auditory cortex (A1); and for SZS compared to NP in the right superior temporal gyrus (STG). Further, we explored the effective connectivity differences between these regions, which also capture the know auditory prediction error network architecture. Dynamic Causal Modelling with Parametric Empirical Bayes analysis revealed stronger left A1 intrinsic connectivity in the SZS compared to the NP group, which was also related to better regularity learning. Furthermore, people that experienced more hallucinations and general psychotic-like symptoms had decreased intrinsic connectivity in the right IFG, which was also found to be related to poorer regularity learning. DISCUSSION: The findings provide evidence that reductions in auditory prediction error signaling is specific to the schizophrenia spectrum, related to attenuation in MMN and decreased activity in superior temporal gyrus. However, the results also support the notion of the psychosis continuum, with psychotic experiences across the three groups being related to poorer regularity learning and decreases in P300, suggesting a weaker prediction model of sensory probabilities. Weaker right IFG intrinsic connectivity may underlie impaired prediction formation, in patients experiencing hallucinations, and people within the general population who also experience psychotic-like symptoms. We suggest that increased intrinsic left A1 connectivity may play a compensatory role in SZS compared to other patient groups during regularity learning.

Background: The body is capable of signaling a multitude of states and dispositions to others before proximal interpersonal interaction is necessary. Decisions are made as to whether to approach or avoid someone before one can perceive the other individual’s face. How individuals with schizophrenia perceive and recognize these nonverbal, bodily signals is less well understood. To further elucidate the mechanisms underlying social cognitive deficits of schizophrenia, we presented dynamic “avatars” expressing a range of emotional and social traits and asked participants to identify them.

Holistic processing and face space coding are widely considered primary perceptual mechanisms behind good face recognition. Here, however, we present the case of S.P., a developmental prosopagnosic who demonstrated severe impairments in face memory and face perception, yet showed normal holistic processing and face space coding. Across three composite experiments, S.P. showed normal-strength holistic processing for upright faces and no composite effect for inverted faces. Across five aftereffect experiments, S.P. showed normal-sized face aftereffects, which derived normally from face space rather than shape-generic mechanisms. The case of S.P. implies: (a) normal holistic processing and face space coding can be insufficient for good face recognition even when present in combination; and (b) the focus of recent literature on holistic processing and face space should be expanded to include other potential face processing mechanisms (e.g., part-based processing). Our article also highlights the importance of internal task reliability in drawing inferences from single-case studies.