BRAIN COMMUNICATION IN SCHIZOPHRENIA: INSIGHT FROM THE PREVENT STUDY

Il ruolo del corpo calloso nella comunicazione interemisferica \ue8 documentato nell'uomo. Alterazioni della comunicazione interemisferica sono state evidenziate nei disturbi psichiatrici, soprattutto nella schizofrenia (Mohr et al., 2000). lo scopo dello studio \ue8 valutare la connettivit\ue0 interemisferica in un campione di soggetti con schizofrenia comparati a controlli sani mediante la risonanza magnetica funzionale. i risultati ottenuti dimostrano la presenza nei pazienti di diffuse iperattivazioni e ipoattivazioni localizzate, verosimilmente riconducibili a una condizione di overworking diffuso cerebrale durante l'esecuzione della task.Background: The role of the CC in sustaining inter-hemispheric connectivity is well documented in humans both for simple and more cognitively demanding tasks. Alterations in inter-hemispheric communication have been shown in schizophrenia subjects (Mohr et al., 2000) with few studies investigating interhemispheric information exchange using behavioural tasks. In contrast some studies found no differences between schizophrenia patients and normal controls, but also excessively slow responses involving the left hemisphere were present in schizophrenics (Shelton & Knight, 1984; Florio and colleagues, 2002; Bellani et al., 2010). Moreover, there is some evidence of abnormally long interhemispheric transfer time (IHTT) in schizophrenia showed by evoked related potential studies (Barnett et al., 2005; Barnett and Kirk 2005; Endrass et al., 2002). Objectives: In the present study, we aimed to study interhemispheric connectivity in a sample of schizophrenia patients and healthy controls using functional Magnetic Resonance Imaging (fMRI) and a visuomotor task named Poffenberger\u2019s task . Methods: A sample of 21 healthy controls and 21 schizophrenia patients underwent a simple visual manual reaction-time (RT) task (Poffenberger\u2019s paradigm) during a fMRI session. This paradigm was employed to measure interhemispheric transfer (IT) by subtracting mean reaction times (RT) for the uncrossed hemifield-hand conditions, that is, those conditions not requiring an IT, from the crossed hemifield-hand conditions, that is, those conditions requiring an IT to relay visual information from the hemisphere of entry to the hemisphere subserving the response. The obtained difference is widely believed to reflect callosal conduction time. fMRI data were acquired using a 3 Tesla Siemens scanner. We performed separate One Sample t-test CUD for patients and controls. Results: The blood oxygenation level-dependent (BOLD) response was present in the genu of corpus callosum in males and females separately and in the whole group (p<0.01 uncorrected). In the patient group, there is a diffuse hyperactivation in the brain (p<0.01). Hyper-activations and hypo-activations were found in the schizophrenic patients in comparison to the healthy controls depending on the area of the brain and on the task. The blood oxygenation level-dependent (BOLD) response was higher in the pre-central gyrus (frontal motor cortex), middle frontal gyrus, inferior frontal gyrus, post central gyrus (parietal sensory cortex), and in the putamen for the crossed-uncrossed difference condition. With p<0.01 (uncorrected) activations were wider and also included corpus callosum. Interestingly when females and males are analysed separately, significant hyperactivations persisted only in female SCZ patients excepted for putamen and precentral gyrus that were no more significant. Conclusions: Our results confirmed previous published studies in humans that tested the implication of corpus callosum in visuo-motor task. In particular our results confirmed the structure-function relationship that involves brain interhemispheric processes in a sample healthy subjects and referred to a specific activation restricted in the genu of corpus callosum. The genu is thought to be associated with the prefrontal cortex to the premotor interhemispheric transfer. We investigated the role of the CC in regulating functional communication between the hemispheres in schizophrenia patients compared to healthy controls and hyper-activations and hypo-activations were found. These results may reflect a brain diffuse overwork related to the demanding task that is not present in healthy subjects

Language disturbances in ADHD.

This article aims to review the studies exploring language abilities in attention deficit hyperactivity disorder (ADHD; with or without comorbid language impairment) focusing on oral speech discrimination, listening comprehension, verbal and spatial working memory as well as on discourse analysis and pragmatic aspects of communication and language comprehension

Childhood adversities and bipolar disorder: a neuroimaging focus

Early-life adverse events or childhood adversities (CAs) are stressors and harmful experiences severely impacting on a child's wellbeing and development. Examples of CAs include parental neglect, emotional and physical abuse and bullying. Even though the prevalence of CAs and their psychological effects in both healthy and psychiatric populations is established, only a paucity of studies have investigated the neurobiological firms associated with CAs in bipolar disorder (BD). In particular, the exact neural mechanisms and trajectories of biopsychosocial models integrating both environmental and genetic effects are still debated. Considering the potential impact of CAs on BD, including its clinical manifestations, we reviewed existing literature discussing the association between CAs and brain alterations in BD patients. Results showed that CAs are associated with volume alterations of several grey matter regions including the hippocampus, thalamus, amygdala and frontal cortex. A handful of studies suggest the presence of alterations in the corpus callosum and the pre-fronto-limbic connectivity at rest. Alterations in these regions of the brain of patients with BD are possibly due to the effect of stress produced by CAs, being hippocampus part of the hypothalamus-pituitary-adrenal axis and thalamus together with amygdala filtering sensory information and regulating emotional responses. However, results are mixed possibly due to the heterogeneity of methods and study design. Future neuroimaging studies disentangling between different types of CAs or differentiating between BD sub-types are needed in order to understand the link between CAs and BD

A critical overview of tools for assessing cognition in bipolar disorder

Cognitive deficits are prevalent in bipolar disorder even during the euthymic phase, having a negative impact on global functioning and quality of life. As such, more and more mental health professionals agree that neuropsychological assessment should be considered an essential component of the clinical management of bipolar patients. However, no gold standard tool has been established so far. According to bipolar disorder experts targeting cognition, appropriate cognitive tools should be brief, easy to administer, cost-effective and validated in the target population. In this commentary, we critically appraised the strengths and limitations of the tools most commonly used to assess cognitive functioning in bipolar patients, both for screening and diagnostic purposes

Neuroimaging studies exploring the neural basis of social isolation

According to the social brain hypothesis, the human brain includes a network designed for the processing of social information. This network includes several brain regions that elaborate social cues, interactions and contexts, i.e. prefrontal paracingulate and parietal cortices, amygdala, temporal lobes and the posterior superior temporal sulcus. While current literature suggests the importance of this network from both a psychological and evolutionary perspective, little is known about its neurobiological bases. Specifically, only a paucity of studies explored the neural underpinnings of constructs that are ascribed to the social brain network functioning, i.e. objective social isolation and perceived loneliness. As such, this review aimed to overview neuroimaging studies that investigated social isolation in healthy subjects. Social isolation correlated with both structural and functional alterations within the social brain network and in other regions that seem to support mentalising and social processes (i.e. hippocampus, insula, ventral striatum and cerebellum). However, results are mixed possibly due to the heterogeneity of methods and study design. Future neuroimaging studies with longitudinal designs are needed to measure the effect of social isolation in experimental v. control groups and to explore its relationship with perceived loneliness, ultimately helping to clarify the neural correlates of the social brain

Developing a brief tele-psychotherapy model for COVID-19 patients and their family members

Objective: The COVID-19 pandemic is negatively impacting the mental health of COVID-19 patients and family members. Given the restrictions limiting in person contact to reduce the spread of the virus, a digital approach is needed to tackle the psychological aftermath of the pandemic. We present the development of a brief remote psychotherapy program for COVID-19 patients and/or their relatives. Methods: We first reviewed the literature on psychotherapeutic interventions for COVID-19 related symptoms. Based on this evidence, we leveraged ongoing clinical experiences with COVID-19 survivors and family members to design an intervention model that could be disseminated and integrated into the workflow of the mental health system. Results: This 8-session model -inspired by constructivist and hermeneutic-phenomenological therapies- serves COVID-19 patients during hospitalization, remission and recovery. This model can also be delivered to people dealing with the COVID-19 hospitalization/discharge of a family member, or the loss of a family member due to COVID-19. Conclusion: We described a remote psychotherapeutic approach to tackle the COVID-19 pandemic psychological aftermath. To date, the approach seems feasible and highly customizable to patients' needs. Studies are underway to test its preliminary efficacy. Once proven efficacious, this treatment model could provide a blueprint for future tele-psychology wide-scale interventions

Adult mild encephalitis with reversible splenial lesion associated with delirious mania: a case report

Mild encephalitis with reversible splenial lesion is a rare clinic-radiological entity presenting with neurological and neuropsychiatric symptoms associated with cerebral lesion/s. Delirious mania is a severe psychiatric syndrome characterized by acute onset of delirium, excitement, and psychosis with a high mortality rate. In this paper, we present a case report of mild encephalitis with reversible splenial lesion clinically presenting as delirious mania and evolving into life-threatening multi-organ failure. The patient was treated with aripiprazole and benzodiazepine with poor effect and, after 4 days, the patient's condition significantly worsened requiring transfer to the intensive care unit where deep sedation with propofol was started. Our findings are in contrast with the traditional literature description of self-resolving and harmless mild encephalitis with reversible splenial lesion. Moreover, rapid clinical recovery and the progressive improvement of psychiatric symptoms after deep sedation with propofol in this case-considering propofol's neuroprotective and anti-inflammatory effects-supports the notion of propofol-mediated deep sedation for the treatment of severe manic symptoms associated with life-threatening conditions. Little is known about neural markers of the manic state, and the corpus callosum has been described to be involved in bipolar disorder. Abnormalities in this structure may represent a marker of vulnerability for this disorder

Hippocampal volume as a putative marker of resilience or compensation to minor depressive symptoms in a nonclinical sample

Case-control studies in major depression have established patterns of regional gray matter loss, including the hippocampus, which might show state-related effects dependent on disease stage. However, there is still limited knowledge on compensation effects that might occur in people resilient to depression showing only subclinical symptoms. We used voxel-based morphometry on a multicenter data set of 409 healthy nonclinical subjects to test the hypothesis that local hippocampal volume would be inversely correlated with subclinical depressive symptoms [Symptom Checklist 90-Revised (SCL-90-R) depression scores]. Our region-of-interest results show a significant (p = 0.042, FWE cluster-level corrected) positive correlation of SCL-90-R scores for depression and a left hippocampus cluster. Additionally, we provide an exploratory finding of gyrification, a surface-based morphometric marker, correlating with a right postcentral gyrus cluster [p = 0.031, family-wise error (FWE) cluster-level corrected]. Our findings provide first preliminary evidence of an inverse relationship for subjects in the absence of clinical depression and might thus point to processes related to compensation. Similar effects have been observed in remission from major depression and thus deserve further study to evaluate hippocampal volume not only as a state-dependent marker of disease but also of resilience

Psychophysiological responses to psychological stress exposure and neural correlates in adults with mental disorders: a scoping review

Introduction: The dysregulation of psychophysiological responses to mental stressors is a common issue addressed in individuals with psychiatric conditions, while brain circuit abnormalities are often associated with psychiatric conditions and their manifestations. However, to our knowledge, there is no systematic overview that would comprehensively synthesize the literature on psychophysiological responses during laboratory-induced psychosocial stressor and neural correlates in people with mental disorders. Thus, we aimed to systematically review the existing research on psychophysiological response during laboratory-induced stress and its relationship with neural correlates as measured by magnetic resonance imaging techniques in mental disorders. Methods: The systematic search was performed on PubMed/Medline, EBSCOhost/PsycArticles, Web of Science, and The Cochrane Library databases during November 2021 following the PRISMA guidelines. Risk of bias was evaluated by employing the checklists for cross-sectional and case-control studies from Joanna Briggs Institute (JBI) Reviewers Manual. Results: Out of 353 de-duplicated publications identified, six studies were included in this review. These studies were identified as representing two research themes: (1) brain anatomy and psychophysiological response to mental stress in individuals with mental disorders, and (2) brain activity and psychophysiological response to mental stress in individuals with mental disorders. Conclusions: Overall, the evidence from studies exploring the interplay between stress psychophysiology and neural correlates in mental disorders is limited and heterogeneous. Further studies are warranted to better understand the mechanisms of how psychophysiological stress markers interplay with neural correlates in manifestation and progression of psychiatric illnesses