Neuropsychological functioning in adolescents and young adults at genetic risk for schizophrenia and affective psychoses: results from the Harvard and Hillside Adolescent High Risk Studies

Long-term trajectories of clinical staging in first-episode psychosis and their associated cognitive outcome: A 21-year follow-up study

Cognitive deficits are already present before psychosis onset but are a key feature of first-episode psychosis (FEP). The objective of this study was to investigate the cognitive outcomes of a cohort of FEP patients who were diagnosed using the clinical staging approach and were followed for up to 21 years. We analyzed data from 173 participants with first-admission psychosis who were followed-up for a mean of 20.9 years. The clinical staging assessment was adapted from the clinical staging framework developed by McGorry et al.1 Cognitive assessment was performed using the MATRICS Consensus Cognitive Battery (MMCB) at the end of follow-up. FEP patients who were longitudinally diagnosed in the lowest clinical stages (stages 2A and 2B) showed better performance in attention, processing speed, and MCCB overall composite score than those in the highest clinical stages (stages 4A and 4B). There was a significant linear trend association between worsening of all MCCB cognitive functions and MCCB overall composite score and progression in clinical staging. Furthermore, the interval between two and five years of follow-up appears to be associated with deficits in processing speed as a cognitive marker. Our results support the validation of the clinical staging model over a long-term course of FEP based on neuropsychological performance. A decline in some cognitive functions, such as processing speed, may facilitate the transition of patients to an advanced stage during the critical period of first-episode psychosis.

Exploring the Genetic Landscape of Mild Behavioral Impairment as an Early Marker of Cognitive Decline: An Updated Review Focusing on Alzheimer's Disease

The clinical features and pathophysiology of neuropsychiatric symptoms (NPSs) in dementia have been extensively studied. However, the genetic architecture and underlying neurobiological mechanisms of NPSs at preclinical stages of cognitive decline and Alzheimer's disease (AD) remain largely unknown. Mild behavioral impairment (MBI) represents an at-risk state for incident cognitive impairment and is defined by the emergence of persistent NPSs among non-demented individuals in later life. These NPSs include affective dysregulation, decreased motivation, impulse dyscontrol, abnormal perception and thought content, and social inappropriateness. Accumulating evidence has recently begun to shed more light on the genetic background of MBI, focusing on its potential association with genetic factors related to AD. The Apolipoprotein E (APOE) genotype and the MS4A locus have been associated with affective dysregulation, ZCWPW1 with social inappropriateness and psychosis, BIN1 and EPHA1 with psychosis, and NME8 with apathy. The association between MBI and polygenic risk scores (PRSs) in terms of AD dementia has been also explored. Potential implicated mechanisms include neuroinflammation, synaptic dysfunction, epigenetic modifications, oxidative stress responses, proteosomal impairment, and abnormal immune responses. In this review, we summarize and critically discuss the available evidence on the genetic background of MBI with an emphasis on AD, aiming to gain insights into the potential underlying neurobiological mechanisms, which till now remain largely unexplored. In addition, we propose future areas of research in this emerging field, with the aim to better understand the molecular pathophysiology of MBI and its genetic links with cognitive decline.

Clinical and cognitive characteristics of subjects with schizophrenia and childhood attention-deficit/hyperactivity disorder: Results from the multicentric FACE-SZ cross-sectional dataset

BACKGROUND

Childhood Attention-deficit/hyperactivity disorder (C-ADHD) is a neurodevelopmental disorder, associated with an increased risk of subsequent schizophrenia. The objective of the present study was to determine the prevalence of C-ADHD in schizophrenia and the clinical and cognitive characteristics associated with C-ADHD history in schizophrenia.

METHODS

569 subjects with schizophrenia (74 % men, mean age 30.8) were included in ten expert centers at a national level and tested with a comprehensive battery of clinician-rated, patient-reported scales and cognitive tests. C-ADHD was assessed with the WURS (Wender Utah Rating Scale) self-report questionnaire. Multivariate, correlation, and principal component analyses (PCA) were conducted.

RESULTS

Thirty-nine subjects (N = 39, 6.9 %) were classified in the C-ADHD group. Compared to those without C-ADHD, subjects with C-ADHD were more frequently male, had lower education levels, more severe positive clinical symptoms, more subjective cognitive deficits complaints, and lower medication adherence with small to medium effect sizes. Two cognitive components emerged from the PCA, one component including perceptual reasoning and working memory, and another component including visuospatial search and graphomotor speed, cognitive inhibition/flexibility and central executive functioning. Both components were associated with lower performances in the C-ADHD group.

CONCLUSIONS

C-ADHD is frequent in schizophrenia and associated with more severe positive symptoms and impaired cognitive performances compared to those without C-ADHD. This suggests that the pathophysiological mechanisms contributing to these disorders may lead to the worsening of the cognitive functioning in patients with both disorders. C-ADHD is a relevant clinical marker to discriminate subgroups of schizophrenia with different profiles for a precision-psychiatry approach.

The Risk for Schizophrenia-Bipolar Spectrum: Does the Apple Fall Close to the Tree? A Narrative Review

Schizophrenia (SCZ) and bipolar disorder (BD) are severe psychiatric disorders that share clinical features and several risk genes. Important information about their genetic underpinnings arises from intermediate phenotypes (IPs), quantifiable biological traits that are more prevalent in unaffected relatives (RELs) of patients compared to the general population and co-segregate with the disorders. Within IPs, neuropsychological functions and neuroimaging measures have the potential to provide useful insight into the pathophysiology of SCZ and BD. In this context, the present narrative review provides a comprehensive overview of the available evidence on deficits in neuropsychological functions and neuroimaging alterations in unaffected relatives of SCZ (SCZ-RELs) and BD (BD-RELs). Overall, deficits in cognitive functions including intelligence, memory, attention, executive functions, and social cognition could be considered IPs for SCZ. Although the picture for cognitive alterations in BD-RELs is less defined, BD-RELs seem to present worse performances compared to controls in executive functioning, including adaptable thinking, planning, self-monitoring, self-control, and working memory. Among neuroimaging markers, SCZ-RELs appear to be characterized by structural and functional alterations in the cortico-striatal-thalamic network, while BD risk seems to be associated with abnormalities in the prefrontal, temporal, thalamic, and limbic regions. In conclusion, SCZ-RELs and BD-RELs present a pattern of cognitive and neuroimaging alterations that lie between patients and healthy individuals. Similar abnormalities in SCZ-RELs and BD-RELs may be the phenotypic expression of the shared genetic mechanisms underlying both disorders, while the specificities in neuropsychological and neuroimaging profiles may be associated with the differential symptom expression in the two disorders.

Are neurocognitive abilities and social cognition related to social and role functioning in familial high risk group for psychosis?

AIMS

In this study, we aimed to compare neurocognitive abilities and social cognitive features among adolescent offspring of psychotic individuals and healthy controls.

METHODS

The study sample was composed of offspring of patients with psychotic disorders (n = 30), the high risk group (HR), and age and sex matched healthy controls (n = 32) the Control Group (CG). The psychiatric diagnoses were established by using the KD-SADS. Strengths and Difficulties Questionnaire adolescent and parent forms (SDQ-A, SDQ-P) were used. General functioning status were evaluated by The Children's Global Assessment Scale (CGAS) and Global Functioning Scale: Social and Role Functioning. Wisconsin Cart Sorting Test, Controlled Oral Word Association Test, California Verbal Learning Test, Stroop Colour and Word Test and Trail Making Tests A and B were used to assess neurocognitive abilities; to assess social cognition and empathy skills DANVA-2 and Bryant Empathy Scale were used, respectively.

RESULTS

Among HR 53.33% had at least one psychopathology. SDQ-A, SDQ-P scores were significantly higher, and CGAS, social and role functioning scores were significantly lower in HR. Neurocognitive test scores were significantly worse except for SCWT scores in the HR. No significant differences were obtained in social cognition. A variety of the neurocognitive abilities were significantly correlated with the role functioning. In regression analyses, the most predictive scores were WCST total correct scores and role functioning score.

CONCLUSIONS

HR group showed more impairments in neurocognition, social, role and overall functioning, whereas there was no significant difference in terms of social cognition. Disturbances in neurocognition were correlated with impairments in role functioning.

Brain structural abnormalities of the associative striatum in adolescents and young adults at genetic high-risk of schizophrenia: Implications for illness endophenotypes

OBJECTIVE

Dysfunction in cortico-striatal circuitry represents a core component of the pathophysiology in schizophrenia (SZ) but its potential as a candidate endophenotype of the illness is often confounded by neuroleptic medication.

METHODS

Accordingly, 26 adolescent and young adult participants at genetic high-risk for schizophrenia, but who were asymptomatic and neuroleptic naïve, and 28 age-matched controls underwent 1.5T structural magnetic resonance imaging of the striatum, manually parcellated into limbic (LST), associative (AST), and sensorimotor (SMST) functional subregions.

RESULTS

In relation to their age peers, participants at genetic high-risk for schizophrenia showed overall lower striatal gray matter volume with their most pronounced loss, bilaterally in the AST, but not the LST or SMST. Neuropsychological testing revealed reduced executive functioning for genetically at-risk participants, although the groups did not differ significantly in overall intelligence or oral reading. For controls but not for at-genetic high-risk participants, stronger executive functioning correlated with increased bilateral AST volume.

CONCLUSIONS

Reduced bilateral AST volume in genetic high-risk adolescents and young adults, accompanied by heritable loss of higher cognitive brain-behavior relationships, might serve as a useful endophenotype of SZ.

Neurocognitive functioning in adult and adolescent offspring of parents with schizophrenia

INTRODUCTION

Neurocognitive deficits have been proposed as endophenotypes for schizophrenia. Although neurocognitive functioning has been studied extensively in first-degree relatives of schizophrenia patients at single time points, little is known about the change or continuity in deficits across development.

METHOD

The longitudinal sample was composed of 86 nonpsychotic participants who had a parent with schizophrenia (n = 28), a parent with a nonschizophrenia mental disorder (n = 31) or parents without mental illness (n = 27). Executive functioning (EF) was assessed during adolescence (M = 18 years) and adulthood (M = 32 years); attention and memory were assessed at adulthood.

RESULTS

The schizophrenia group, as adults, showed deficits in attention and memory relative to the no mental illness group. Only on one memory task did the schizophrenia group perform more poorly than the other mental illness group. Executive functioning improved with age for all three groups on Wisconsin Card Sorting Test perseverative errors; the rate of improvement was significantly slower for the schizophrenia and the other mental illness groups, compared to the no mental illness group. Stability in EF functioning over the 16-year period, measured by intraclass correlations, was low.

CONCLUSIONS

Adults at familial risk for schizophrenia showed deficits in neurocognitive functioning. The similarity of performance between those whose parents had schizophrenia and those whose parents had other mental illness, in all but the measures of memory, raises the question as to whether the neurocognitive functions examined are endophenotypes of vulnerability to schizophrenia specifically. Modest stability of EF and improved performance with age may reflect cortical maturation during early adulthood.

Neurocognitive Development in Children at Familial High Risk of Schizophrenia or Bipolar Disorder

IMPORTANCE

Neurocognitive impairments exist in children at familial high risk (FHR) of schizophrenia and bipolar disorder. Studies on preadolescent developmental courses of neurocognition are important to describe shared and distinct neurodevelopmental pathways in these groups.

OBJECTIVE

To assess the development in specific neurocognitive functions from age 7 to 11 years in children at FHR of schizophrenia or bipolar disorder compared with children in a population-based control (PBC) group.

DESIGN, SETTING, AND PARTICIPANTS

The Danish High Risk and Resilience Study is a prospective, longitudinal, cohort study that collected data from January 1, 2013, to January 31, 2016 (phase 1), and from March 1, 2017, to June 30, 2020 (phase 2). Data were collected at 2 university hospitals in Denmark, and participants included 520 children at FHR of schizophrenia or bipolar disorder along with a PBC group matched with the group of children at FHR of schizophrenia by age, sex, and municipality.

EXPOSURES

Parental schizophrenia, bipolar disorder, or neither.

MAIN OUTCOMES AND MEASURES

Neurocognitive functioning was assessed with validated tests of intelligence, processing speed, attention, memory, verbal fluency, and executive functioning. Multilevel mixed-effects linear regression models with maximum likelihood estimation were used to estimate neurocognitive development from age 7 to 11 years.

RESULTS

At 4-year follow-up, a total of 451 children (mean [SD] age; 11.9 [0.2] years; 208 girls [46.1%]) underwent neurocognitive testing. There were a total of 170 children at FHR of schizophrenia (mean [SD] age, 12.0 [0.3]; 81 girls [47.7%]), 103 children at FHR of bipolar disorder (mean [SD] age, 11.9 [0.2] years; 45 girls [43.7%]), and 178 children in the PBC group (mean [SD] age, 11.9 [0.2] years; 82 girls [46.1%]). At either age 7 or 11 years or at both assessments, 520 children participated in the neurocognitive assessment and were therefore included in the analyses. When correcting for multiple comparisons, no statistically significant time × group interactions were observed across the 3 groups. Compared with the PBC group at 4-year follow-up, children at FHR of schizophrenia showed significant neurocognitive impairment in 7 of 24 neurocognitive measures (29.2%; Cohen d range, 0.29-0.37). Compared with children at FHR of bipolar disorder, children at FHR of schizophrenia had significant neurocognitive impairment in 5 of 24 measures (20.8%; Cohen d range, 0.29-0.38). Children at FHR of bipolar disorder and those in the PBC group did not differ significantly.

CONCLUSIONS AND RELEVANCE

In this cohort study, findings suggest that neurocognitive maturation was comparable across groups of children at FHR of schizophrenia or bipolar disorder compared with PBCs from age 7 to 11 years. Compared with the PBC group, children at FHR of schizophrenia demonstrated widespread, stable, neurocognitive impairments during this period, whereas children at FHR of bipolar disorder showed no neurocognitive impairments, which may indicate distinct neurodevelopmental pathways in children at FHR of schizophrenia and bipolar disorder.

A family study on first episode of psychosis patients: Exploring neuropsychological performance as an endophenotype

INTRODUCTION

Family studies provide a suitable approach to analyzing candidate endophenotypes of schizophrenia, including cognitive features.

OBJECTIVE

To characterize different neurocognitive functions in a group of patients with first episode of psychosis (FEP), their first-degree relatives (parents and siblings), and healthy controls (HC), in order to identify potential endophenotypes for schizophrenia spectrum disorders (SSD).

METHODS

Participants were assessed in the context of a national project in Spain called PAFIP-FAMILIAS. They completed the same neuropsychological battery, which included tests of verbal memory, visual memory, processing speed, working memory, executive functions, motor dexterity, attention, and theory of mind. Group comparisons were performed using one-way ANOVA, followed by tests of multiple comparisons when appropriate.

RESULTS

One hundred thirty-three FEP patients were included, as well as 244 of their first-degree relatives (146 parents and 98 siblings) and 202 HC. In general, relatives showed an intermediate performance between the HC and the FEP patients in all neurocognitive domains. However, the domains of executive functions and attention stood out, as relatives (especially parents) showed similar performance to FEP patients. This was replicated when selecting patients subsequently diagnosed with schizophrenia and their relatives.

CONCLUSION

These findings suggest that executive and attention dysfunctions might have a family aggregation and could be relevant cognitive endophenotypes for psychotic disorders. The study shows the potential of exploring intra-family neuropsychological performance supporting neurobiological and genetic research in SSD.

Cognitive reserve and its correlates in child and adolescent offspring of patients diagnosed with schizophrenia or bipolar disorder

AIM

To analyze cognitive reserve (CR) in child and adolescent offspring of patients diagnosed with schizophrenia (SZ-off) or bipolar disorder (BD-off) and compare them with a group of community controls (CC-off). We also aimed to investigate whether there was an association between CR and clinical and neuropsychological variables according to group.

METHODS

The study included 46 SZ-off, 105 BD-off and 102 CC-off. All participants completed assessments regarding CR and clinical, neuropsychological and psychosocial functioning. CR was measured with a proxy based on premorbid intelligence, parental occupational level, educational attainment, developmental milestones and sociability. The clinical assessment included the Kiddie Schedule for Affective Disorders and Schizophrenia, Present and Lifetime, the Semi-structured Interview for Prodromal Syndromes, and the Global Assessment Functioning scale. The neuropsychological assessment included measures of executive functioning, attention, verbal memory, working memory and processing speed.

RESULTS

SZ-off showed a lower level of CR compared to BD-off and CC-off, while BD-off showed an intermediate level of CR between SZ-off and CC-off. Moreover, an association between higher CR and less lifetime psychopathology, fewer prodromal psychotic symptoms, higher psychosocial functioning, and a higher working memory score was observed in all groups, but it was stronger in SZ-off.

CONCLUSIONS

CR seemed to be associated with psychopathology, clinical symptoms, psychosocial functioning, and some cognitive functions. SZ-off appeared to benefit more from a higher CR, therefore it could be considered a protective factor against the development of clinical symptomatology and cognitive impairment.

The effects of childhood adversity on treatment delays and its components in first-episode psychosis

Apart from increasing risk for psychotic disorders, childhood adversity has been associated with worse outcomes. One way in which childhood adversity may worsen outcomes is by lengthening treatment delays, which are associated with negative impacts. We tested the influence of childhood trauma on treatment delays, measured as the duration of untreated psychosis (DUP), and its help-seeking and referral components, in a first-episode psychosis cohort (N = 203). We accounted for pertinent social (e.g., migrant status) and other determinants (i.e., age at onset, diagnosis, symptoms) of treatment delays. Multiple linear regression analyses revealed that for a one-unit increase in Childhood Trauma Questionnaire (CTQ) scores, average overall DUP increased by 25%. Higher CTQ scores also significantly predicted help-seeking and referral DUPs. Patients with schizophrenia-spectrum psychosis had longer help-seeking and total DUPs than those with affective psychosis. More severe positive symptoms predicted longer help-seeking DUPs, while more severe negative symptoms predicted longer referral DUPs. Indicators of social disadvantage did not affect DUP. Our results show that childhood trauma increases DUP by prolonging the help-seeking process and delaying access to mental healthcare even after help is sought. Early identification of psychosis among populations with trauma histories seems warranted and can likely positively impact outcomes.

Altered working memory-related brain activity in children at familial high risk for psychosis: A preliminary study

BACKGROUND

Schizophrenia spectrum disorders are heritable illnesses that usually manifest in early adulthood but are increasingly viewed as neurodevelopmental disorders. Functional magnetic resonance imaging (fMRI) studies show altered brain activity during performance of working memory (WM) tasks in both individuals with schizophrenia and their first-degree relatives as compared to healthy controls (HC). This study examined whether similar changes are already present in pre-adolescent children at familial high-risk (FHR) for psychosis.

METHODS

37 children (17 FHR, 20 HC) between 7 and 12 years old participated in this study. WM performance was assessed using the Wechsler Intelligence Scale for Children-IV (WISC-IV). To assess brain activation during WM performance, participants completed a visual block-designed n-back task with 2 conditions (2-back and 0-back) during scanning. fMRI data was preprocessed and analyzed using FSL Feat.

RESULTS

Compared to HC, FHR children showed significantly lower WISC-IV WM scores. In addition, FHR children exhibited hypoactivation in the 2-back (versus 0-back) condition in a cluster encompassing bilateral precuneus and cuneus and right posterior cingulate cortex. There were no significant group-differences in n-back task performance and brain activation. The precuneus cluster was not correlated with n-back performance or WISC WM scores.

CONCLUSIONS

The current results provide preliminary evidence of impaired WM function and altered brain activity during WM performance in children with a familial predisposition for psychosis. Longitudinal studies are needed to determine whether these findings are related to abnormal brain development and predictive of cognitive deficits and psychosis later in life.

Development of visual attention from age 7 to age 12 in children with familial high risk for schizophrenia or bipolar disorder

BACKGROUND

Children with familial high risk of schizophrenia (FHR-SZ) or bipolar disorder (FHR-BP) are at increased risk of developing similar disorders and show cognitive deficits during childhood. The aim of this paper is to investigate visual attention and its developmental trajectories in children with FHR-SZ and with FHR-BP to increase our knowledge about potential cognitive endophenotypes of these two disorders.

METHODS

We compared the performance of 89 children with FHR-SZ (N = 32), FHR-BP (N = 22), and population-based controls (PBC, N = 35) at age 7 to that at age 12 as well as including 133 12-year-old children with FHR-SZ (N = 50), FHR-BP (N = 43) and PBC (N = 40) to investigate visual attention, as part of the Danish High Risk and Resilience Study. We used the TVA-based whole report paradigm, based on the Bundesen's Theory of Visual Attention (TVA) to investigate visual attention.

RESULTS

Children with FHR-SZ that showed deficits in visual processing speed at age 7 improved to a level that was not significantly different from controls at age 12. All children improved over time. We found no attentional deficits in FHR children at age 12.

CONCLUSIONS

On visual attention, children with FHR-SZ did not show developmental deficits or lags and, together with children with FHR-BP, they develop similarly to control children between age 7 to age 12. This emphasizes the potential of beneficial neuroplastic changes in cognitive deficits found at younger ages in children with FHR-SZ. It also highlights the importance of identifying and characterizing cognitive developmental trajectories of high-risk children and provides hope that visual attention may develop appropriately in these groups.

Cognition in offspring of parents with psychotic and non-psychotic severe mental illness

BACKGROUND

Cognitive impairment is a feature of severe mental illness (SMI; schizophrenia, bipolar disorder, major depressive disorder). Psychotic forms of SMI may be associated with greater cognitive impairment, but it is unclear if this differential impairment pre-dates illness onset or whether it reflects a consequence of the disorder. To establish if there is a developmental impairment related to familial risk of psychotic SMI, we investigated cognition in offspring of parents with psychotic and non-psychotic SMI.

METHOD

Participants included 360 children and youth (mean age 11.10, SD 4.03, range 6-24), including 68 offspring of parents with psychotic SMI, 193 offspring of parents with non-psychotic SMI, and 99 offspring of control parents. The cognitive battery assessed a range of functions using standardized tests and executive function tasks from the Cambridge Automated Neuropsychological Test Battery.

RESULTS

Compared to controls, offspring of parents with psychotic SMI performed worse on overall cognition (β = -0.32; p < 0.001) and 6 of 15 cognitive domains, including verbal intelligence, verbal working memory, processing speed, verbal learning and memory, verbal fluency, and sustained attention. Offspring of parents with non-psychotic SMI performed worse than controls on 3 of the 15 domain specific cognitive tests, including verbal intelligence, visual memory and decision-making.

CONCLUSIONS

Widespread mild-to-moderate cognitive impairments are present in young offspring at familial risk for transdiagnostic psychotic SMI. Offspring at familial risk for non-psychotic SMI showed fewer and more specific impairments in the domains of verbal intelligence, visual memory and decision-making.

Neuropsychological, clinical and environmental predictors of severe mental disorders in offspring of patients with schizophrenia

Offspring of individuals with schizophrenia (SZCOff) are at an increased risk for this disorder. Neuropsychological decline is a core feature of the disorder and researchers have reported increasing impairments in cognition during the prodromal phase in high-risk adolescents. Additionally, factors like the presence of prodromal symptoms or specific behavioral patterns could predict, together with neurocognitive functioning, the risk of conversion to severe mental disorders in SCZOff. This study aims to compare the neuropsychological functioning of a sample of 41 SCZOff children and adolescents and 105 community control offspring (CCOff) and to develop a prediction model to examine whether neuropsychological functioning, clinical and behavioral factors predict subsequent risk of severe mental disorders. We collected demographic, clinical and neuropsychological data. We found significant differences between groups in working memory, speed of processing, verbal memory and learning, visual memory and intelligence quotient (IQ). The socioeconomic status, verbal memory, working memory and positive prodromal symptoms predicted a significant proportion of the dependent variable variance. In conclusion, SCZOff showed neurocognitive impairments in several neuropsychological domains compared to CCOff. Neuropsychological functioning, environmental factors and positive prodromal symptoms could predict the risk of onset of severe mental disorders in SCZOff.

Support Vector Machine-Based Schizophrenia Classification Using Morphological Information from Amygdaloid and Hippocampal Subregions

Structural changes in the hippocampus and amygdala have been demonstrated in schizophrenia patients. However, whether morphological information from these subcortical regions could be used by machine learning algorithms for schizophrenia classification were unknown. The aim of this study was to use volume of the amygdaloid and hippocampal subregions for schizophrenia classification. The dataset consisted of 57 patients with schizophrenia and 69 healthy controls. The volume of 26 hippocampal and 20 amygdaloid subregions were extracted from T1 structural MRI images. Sequential backward elimination (SBE) algorithm was used for feature selection, and a linear support vector machine (SVM) classifier was configured to explore the feasibility of hippocampal and amygdaloid subregions in the classification of schizophrenia. The proposed SBE-SVM model achieved a classification accuracy of 81.75% on 57 patients and 69 healthy controls, with a sensitivity of 84.21% and a specificity of 81.16%. AUC was 0.8241 (p < 0.001 tested with 1000-times permutation). The results demonstrated evidence of hippocampal and amygdaloid structural changes in schizophrenia patients, and also suggested that morphological features from the amygdaloid and hippocampal subregions could be used by machine learning algorithms for the classification of schizophrenia.

Neuroprogression across the Early Course of Psychosis

Psychotic disorders are severe, debilitating, and even fatal. The development of targeted and effective interventions for psychosis depends upon on clear understanding of the timing and nature of disease progression to target processes amenable to intervention. Strong evidence suggests early and ongoing neuroprogressive changes, but timing and inflection points remain unclear and likely differ across cognitive, clinical, and brain measures. Additionally, granular evidence across modalities is particularly sparse in the "bridging years" between first episode and established illness-years that may be especially critical for improving outcomes and during which interventions may be maximally effective. Our objective is the systematic, multimodal characterization of neuroprogression through the early course of illness in a cross-diagnostic sample of patients with psychosis. We aim to (1) interrogate neurocognition, structural brain measures, and network connectivity at multiple assessments over the first eight years of illness to map neuroprogressive trajectories, and (2) examine trajectories as predictors of clinical and functional outcomes. We will recruit 192 patients with psychosis and 36 healthy controls. Assessments will occur at baseline and 8- and 16-month follow ups using clinical, cognitive, and imaging measures. We will employ an accelerated longitudinal design (ALD), which permits ascertainment of data across a longer timeframe and at more frequent intervals than would be possible in a single cohort longitudinal study. Results from this study are expected to hasten identification of actionable treatment targets that are closely associated with clinical outcomes, and identify subgroups who share common neuroprogressive trajectories toward the development of individualized treatments.

Maternal Bacterial Infection During Pregnancy and Offspring Risk of Psychotic Disorders: Variation by Severity of Infection and Offspring Sex

OBJECTIVE

Previous studies suggest that prenatal immune challenges may elevate the risk of schizophrenia and related psychoses in offspring, yet there has been limited research focused on maternal bacterial infection. The authors hypothesized that maternal bacterial infection during pregnancy increases offspring risk of psychotic disorders in adulthood, and that the magnitude of this association varies as a function of severity of infectious exposure and offspring sex.

METHODS

The authors analyzed prospectively collected data from 15,421 pregnancies among women enrolled between 1959 and 1966 at two study sites through the Collaborative Perinatal Project. The sample included 116 offspring with confirmed psychotic disorders. The authors estimated associations between maternal bacterial infection during pregnancy and psychosis risk over the subsequent 40 years, stratified by offspring sex and presence of reported parental mental illness, with adjustment for covariates.

RESULTS

Maternal bacterial infection during pregnancy was strongly associated with psychosis in offspring (adjusted odds ratio=1.8, 95% CI=1.2-2.7) and varied by severity of infection and offspring sex. The effect of multisystemic bacterial infection (adjusted odds ratio=2.9, 95% CI=1.3-5.9) was nearly twice that of less severe localized bacterial infection (adjusted odds ratio=1.6, 95% CI=1.1-2.3). Males were significantly more likely than females to develop psychosis after maternal exposure to any bacterial infection during pregnancy.

CONCLUSIONS

The study findings suggest that maternal bacterial infection during pregnancy is associated with an elevated risk for psychotic disorders in offspring and that the association varies by infection severity and offspring sex. These findings call for additional investigation and, if the findings are replicated, public health and clinical efforts that focus on preventing and managing bacterial infection in pregnant women.

Social Cognition, Language, and Social Behavior in 7-Year-Old Children at Familial High-Risk of Developing Schizophrenia or Bipolar Disorder: The Danish High Risk and Resilience Study VIA 7-A Population-Based Cohort Study

OBJECTIVE

To characterize social cognition, language, and social behavior as potentially shared vulnerability markers in children at familial high-risk of schizophrenia (FHR-SZ) and bipolar disorder (FHR-BP).

METHODS

The Danish High-Risk and Resilience Study VIA7 is a multisite population-based cohort of 522 7-year-old children extracted from the Danish registries. The population-based controls were matched to the FHR-SZ children on age, sex, and municipality. The FHR-BP group followed same inclusion criteria. Data were collected blinded to familial high-risk status. Outcomes were social cognition, language, and social behavior.

RESULTS

The analysis included 202 FHR-SZ children (girls: 46%), 120 FHR-BP children (girls: 46.7%), and 200 controls (girls: 46.5%). FHR-SZ children displayed significant deficits in language (receptive: d = -0.27, P = .006; pragmatic: d = -0.51, P < .001), social responsiveness (d = -0.54, P < .001), and adaptive social functioning (d = -0.47, P < .001) compared to controls after Bonferroni correction. Compared to FHR-BP children, FHR-SZ children performed significantly poorer on adaptive social functioning (d = -0.29, P = .007) after Bonferroni correction. FHR-BP and FHR-SZ children showed no significant social cognitive impairments compared to controls after Bonferroni correction.

CONCLUSION

Language, social responsiveness, and adaptive social functioning deficits seem associated with FHR-SZ but not FHR-BP in this developmental phase. The pattern of results suggests adaptive social functioning impairments may not be shared between FHR-BP and FHR-SZ in this developmental phase and thus not reflective of the shared risk factors for schizophrenia and bipolar disorder.

Longitudinal Cognitive Performance in Individuals at Ultrahigh Risk for Psychosis: A 10-year Follow-up

It remains unclear whether the onset of psychosis is associated with deterioration in cognitive performance. The aim of this study was to examine the course of cognitive performance in an ultrahigh risk (UHR) cohort, and whether change in cognition is associated with transition to psychosis and change in functioning. Consecutive admissions to Personal Assessment and Crisis Evaluation (PACE) Clinic between May 1994 and July 2000 who had completed a comprehensive cognitive assessment at baseline and follow-up were eligible (N = 80). Follow-up ranged from 7.3 to 13.4 years (M = 10.4 years; SD = 1.5). In the whole sample, significant improvements were observed on the Similarities (P = .03), Information (P < .01), Digit Symbol Coding (P < .01), and Trail Making Test-B (P = .01) tasks, whereas performance on the Rey Auditory Verbal Learning Test (Trials 1-3) declined significantly (P < .01) over the follow-up period. Change in performance on cognitive measures was not significantly associated with transition status. Taking time to transition into account, those who transitioned after 1 year showed significant decline on Digit Symbol Coding, whereas those who did not transition improved on this measure (P = .01; effect size [ES] = 0.85). Small positive correlations were observed between improvements in functioning and improvements in performance on Digit Symbol Coding and Arithmetic (0.24, P = .03 and 0.28, P = .01, respectively). In summary, the onset of psychosis was not associated with deterioration in cognitive ability. However, specific findings suggest that immediate verbal learning and memory, and processing speed may be relevant domains for future risk models and early intervention research in UHR individuals.

Variability of ecological executive function in children and adolescents genetically at high risk for schizophrenia: a latent class analysis

Executive impairments have been observed both in patients with schizophrenia and in their unaffected first-degree relatives. Very few studies have investigated neurocognitive subgroups in unaffected first-degree relatives and in healthy participants using data-driven methods. The study included a high-risk group consisting of 100 unaffected young offspring and siblings of patients with schizophrenia and 198 healthy controls, all aged between 9 and 23 years. Executive function, victimization, and emotional and behavioral problems of participants were assessed by a series of self-report scales. Neurocognitive subgroups were investigated using latent class analysis of executive function measures. Four neurocognitive clusters were identified: a good performance cluster, a good self-control cluster, a low self-control cluster, and a severe impairment cluster. Participants in severe impaired executive function cluster reported a significantly higher level of victimization and had more prominent emotional and behavioral problems than the good performance cluster. Neurocognitive differences between high-risk young people and healthy controls were driven by individuals who have severe and global, rather than selective, executive deficits. Our results may provide clues to an explanation of the mechanisms behind executive impairments in young individuals at genetic risk and help to identify new targets for early interventions.

Clinical Effects of Mindfulness-Based Intervention in Patients With First Episode Psychosis and in Individuals With Ultra-High Risk for Transition to Psychosis: A Review

Objectives: Recent clinical studies and meta-analyses have reported the clinical effects of mindfulness-based interventions as a complementary treatment for patients with schizophrenia, but their possible efficacy in patients with first episode of psychosis (FEP) and in individuals with ultra-high risk (UHR) of transition to psychosis is less clear. Here, we investigated the current evidence on the usefulness of mindfulness-based interventions in these two populations. Methods: We conducted a systematic search of the literature according to the PRISMA guidelines. Results: Among the 102 references retrieved, 9 responded to the inclusion criteria (8 in FEP patients and 1 in UHR individuals). In FEP patients, mindfulness interventions are well-tolerated and have a satisfactory level of adherence. The clinical benefits consist primarily of reduced anxiety and sadness and improved quality of life. None of the studies reported any increase in positive symptoms. Conclusion: Future sham-controlled studies with large sample sizes are needed to definitively conclude on the clinical interest of mindfulness-based interventions in FEP patients and UHR individuals as well as to understand their underlying mechanisms of action.

The research evidence for schizophrenia as a neurodevelopmental disorder

Schizophrenia is a neurodevelopmental disorder that starts very early. In this review we describe the empirical evidence for the neurodevelopmental model. First, by outlining the roots of psychological research that laid the foundation of the model. Thereafter, describing cognitive dysfunction observed in schizophrenia, and the course of cognitive functioning in the illness. Then, research findings that speak for and studies that speak against the view that schizophrenia is a degenerative process is discussed. We find that there is ample evidence that cognitive disturbance is a core element in schizophrenia. However, we have limited understanding of what initiates the abnormal development. This the paper ends with pointing out some of the factors that may trigger the deviant neurocognitive development in schizophrenia.

Longitudinal Cognitive Changes in Young Individuals at Ultrahigh Risk for Psychosis

IMPORTANCE

Cognitive deficits are a key feature of risk for psychosis. Longitudinal changes in cognitive architecture may be associated with the social and occupational functioning in young people.

OBJECTIVES

To examine longitudinal profiles of cognition in individuals at ultrahigh risk (UHR) for psychosis, compared with healthy controls, and to investigate the association of cognition with functioning.

DESIGN, SETTING, AND PARTICIPANTS

This study has a multiple-group prospective design completed in 24 months and was conducted from January 1, 2009, to November 11, 2012, as part of the Longitudinal Youth at-Risk Study conducted in Singapore. Participants either were recruited from psychiatric outpatient clinics, educational institutions, and community mental health agencies or self-referred. Follow-up assessments were performed every 6 months for 2 years or until conversion to psychosis. Individuals with medical causes for psychosis, current illicit substance use, or color blindness were excluded. Data analysis was conducted from June 2014 to May 2018.

MAIN OUTCOMES AND MEASURES

Neuropsychological, perceptual, and social cognitive tasks; semi-structured interviews, and the Structured Clinical Interview for DSM-IV Axis I disorders were administered every 6 months. The UHR status of nonconverters, converters, remitters, and nonremitters was monitored. Cognitive domain scores and functioning were investigated longitudinally.

RESULTS

In total, 384 healthy controls and 173 UHR individuals between ages 14 and 29 years were evaluated prospectively. Of the 384 healthy controls, 153 (39.8%) were female and 231 (60.2%) were male with a mean (SD) age of 21.69 (3.26) years. Of the 173 individuals at UHR for psychosis, 56 (32.4%) were female and 117 (67.6%) were male with a mean (SD) age of 21.27 (3.52) years). After 24 months of follow-up, 383 healthy controls (99.7%) and 122 individuals at UHR for psychosis (70.5%) remained. Baseline cognitive deficits were associated with psychosis conversion later (mean odds ratio [OR], 1.66; combined 95% CI, 1.08-2.83; P = .04) and nonremission of UHR status (mean OR, 1.67; combined 95% CI, 1.09-2.95; P = .04). Five cognitive components-social cognition, attention, verbal fluency, general cognitive function, and perception-were obtained from principal components analysis. Longitudinal component structure change was observed in general cognitive function (maximum vertical deviation = 0.59; χ2 = 8.03; P = .01). Group-by-time interaction on general cognitive function (F = 12.23; η2 = 0.047; P < .001) and perception (F = 8.33; η2 = 0.032; P < .001) was present. Changes in attention (F = 5.65; η2 = 0.013; P = .02) and general cognitive function (F = 7.18; η2 = 0.014; P = .01) accounted for longitudinal changes in social and occupational functioning.

CONCLUSIONS AND RELEVANCE

Individuals in this study who met the UHR criteria appeared to demonstrate cognitive deficits, and those whose UHR status remitted were seen to recover cognitively. Cognition appeared as poor in nonremitters and appeared to be associated with poor functional outcome. This study suggests that cognitive dimensions are sensitive to the identification of young individuals at risk for psychosis and to the longitudinal course of those at highest risk.

School performance from primary education in the adolescent offspring of parents with schizophrenia and bipolar disorder- a national, register-based study

BACKGROUND

Schizophrenia (SZ) and bipolar disorder (BP) are causes of severe disability worldwide and parents' severe mental illness (SMI) is associated with childhood adversity, and socio-emotional and cognitive problems in children. Yet, how parental BP and SZ affect educational attainment in offspring is still unclear.

METHOD

We included all children (N = 684.248) born and living in Denmark between 1986 and 1996 and their parents. Our follow-up lasted from 1986 until children's graduation in 2014. The main outcome variable was their school grades following their primary education. School outcomes were divided into four categories: not graduated, low-grade point average (GPA), medium GPA and high GPA. We then performed a multiple logistic regression with medium GPA as the reference category, with the children of parents without SZ or BP as the reference group.

RESULTS

Children of parents with SZ faced higher odds than their peers of not graduating primary education (OR 2.6), along with low GPA (odds ratios (OR) 1.6) and lower odds for a high GPA (OR 0.7). Moreover, it was the children of mothers rather than fathers with BP who had higher odds of not graduating primary education (OR 1.6). Lastly, child placement was associated with lower grades and lower graduation rates, and outcomes for children of parents with SMI were favorable compared with other children placed in care.

CONCLUSION

For children, parental SZ is associated with lower grades and lower chances for graduating primary education. In contrast, the children of parents with BP were indistinguishable from the reference group regarding school grades. This signifies that specificity of parental severe mental illness is important in relation to educational achievement of children.

Premorbid adjustment predictors of cognitive dysfunction in schizophrenia

Premorbid adjustment (PA) in academic and social domain is a key-predictor of cognitive performance in schizophrenia. Prior studies provided inconsistent findings regarding the differential relationships of PA domains with post-illness cognition. Multivariate associations of academic and social PA in each developmental stage (childhood, early and late adolescence) with post-onset cognitive variables were explored. Furthermore, possible differential relationships of PA domain deterioration courses with post-onset cognitive dysfunction were investigated. Seventy-five schizophrenia patients were evaluated with Premorbid Adjustment Scale (PAS). General cognitive ability, verbal IQ, verbal memory and learning, processing speed, working memory, executive function and premorbid IQ were assessed. Canonical Correlation Analyses revealed that poorer academic PA across childhood and early adolescence was related to worse post-onset verbal IQ, working memory, verbal learning and executive function, while academic PA deterioration between early and late adolescence was associated with poorer verbal learning and executive function and, as further analysis indicated, predicts IQ decline. Academic PA was exclusively associated with post-onset cognitive impairment. New evidence emerged for the specificity of each developmental period in constructing academic PA in its relation to post-illness cognition. Early premorbid academic maladjustment possibly constitutes the onset of a cognitive dysmaturational process which results to post-diagnosis impaired cognition.

An examination of sex differences in neurocognition and social cognition in first-episode psychosis

Due to the dearth and conflicting findings of previous research, it is unclear whether males and females with first-episode psychosis (FEP) differ in their neurocognitive and social cognitive abilities. The aims of the current study were to investigate whether: (i) there are sex differences in neurocognition and social cognition among young people with FEP; and (ii) they resemble those observed in age-matched healthy controls. The current study involved secondary analysis of data from a previous study in which a large neurocognitive and social cognitive battery was administered to 146 individuals with FEP and 46 healthy controls aged 15-25 years. Seven two-way between-groups multivariate analysis of variances revealed that FEP participants were impaired relative to controls on all cognitive domains. Only one main effect of sex was found with males, regardless of group, outperforming females on verbal comprehension. A significant interaction effect was found for information processing speed with FEP females outperforming FEP males on the Symbol Digit Modalities Test; however, post-hoc analysis of the mean difference was not significant. Despite few sex differences, the current study highlights that cognitive impairment is a key feature of FEP that should be a treatment target in early intervention.

Prediction of vocational participation and global role functioning in help-seeking young adults, from neurocognitive, demographic and clinical variables

BACKGROUND

The purpose of this study was to investigate neurocognitive, demographic and clinical correlates of vocational participation among a sample of young help-seeking adults.

METHODS

Young people (18-25 years) accessing an early intervention youth health service participated. The Global Functioning: Role scale and level of vocational participation, participant characteristics (age, gender, socioeconomic background and family history of serious mental illness), distress, psychotic-like experiences, substance use, and mental health diagnoses were recorded. The Cambridge Neuropsychological Testing Automated Battery was used to assess sustained attention, visual memory and executive function.

RESULTS

Of the 107 participants, 33 (31%) were not working or studying and 52 (49%) had a diagnosis of affective disorder. Impairments in neurocognitive tests were evidenced in attention shift, sustained attention target sensitivity, impulsivity and spatial working memory errors. Univariate analyses indicated that information processing and target impulsivity were associated with both vocational participation and global functioning, and that spatial working memory strategy was also associated with vocational participation. After controlling for significant demographic and clinical predictors, strategy formation remained a significant correlate of vocational participation (coefficient (95%CI) = -0.08 (-0.17, -0.01)), but no neurocognitive measures remained significant in the multivariate prediction of global functioning.

LIMITATIONS

Neurocognitive outcomes were assessed at a single time point, factors such as fluctuations in motivation could impact on test results.

CONCLUSIONS

Interventions targeting work and education participation should consider the capacity of vulnerable young people to develop appropriate plans for role success and provide support accordingly. The study also emphasised the importance of high school completion and avoidance of cannabis use, especially in males.

Subcortical surface shape in youth at familial high risk for schizophrenia

Abnormalities in the subcortical brain regions that support cognitive functions have been reported in schizophrenia. Relatives of those with schizophrenia often present with psychosis-like traits (schizotypy) and similar cognition as those with schizophrenia. To evaluate the relationships between subcortical structure, schizotypy, and cognitive function, we assessed shape and volume of the hippocampus, amygdala and thalamus in untreated youth at familial high risk for schizophrenia (HRSZ). The sample consisted of 66 HRSZ and 69 age-matched healthy controls (HC). Subjects' cognitive functions and schizotypy were assessed, and T1-weighted brain MRI were analyzed using the FSL software FIRST. The right hippocampus and right amygdala showed significantly increased concavity (inward displacement) in HRSZ compared to HC. While regional subcortical shape displacements were significantly correlated with sustained attention and executive function scores in HC, fewer correlations were seen in HRSZ. This suggests a possible alteration of the local structure-function relationship in subcortical brain regions of HRSZ for these cognitive domains, which could be related to anomalous plasticity.

Mapping the Consequences of Impaired Synaptic Plasticity in Schizophrenia through Development: An Integrative Model for Diverse Clinical Features

Schizophrenia is associated with alterations in sensory, motor, and cognitive functions that emerge before psychosis onset; identifying pathogenic processes that can account for this multi-faceted phenotype remains a challenge. Accumulating evidence suggests that synaptic plasticity is impaired in schizophrenia. Given the role of synaptic plasticity in learning, memory, and neural circuit maturation, impaired plasticity may underlie many features of the schizophrenia syndrome. Here, we summarize the neurobiology of synaptic plasticity, review evidence that plasticity is impaired in schizophrenia, and explore a framework in which impaired synaptic plasticity interacts with brain maturation to yield the emergence of sensory, motor, cognitive, and psychotic features at different times during development in schizophrenia. Key gaps in the literature and future directions for testing this framework are discussed.

Neuropsychological characteristics of child and adolescent offspring of patients with schizophrenia or bipolar disorder

BACKGROUND

Schizophrenia (SZ) and bipolar disorder (BD) are considered neurobiological disorders which share some clinical, cognitive and neuroimaging characteristics. Studying child and adolescent offspring of patients diagnosed with bipolar disorder (BDoff) or schizophrenia (SZoff) is regarded as a reliable method for investigating early alterations and vulnerability factors for these disorders. This study compares the neuropsychological characteristics of SZoff, BDoff and a community control offspring group (CC) with the aim of examining shared and differential cognitive characteristics among groups.

METHODS

41 SZoff, 90 BDoff and 107 CC were recruited. They were all assessed with a complete neuropsychological battery which included intelligence quotient, working memory (WM), processing speed, verbal memory and learning, visual memory, executive functions and sustained attention.

RESULTS

SZoff and BDoff showed worse performance in some cognitive areas compared with CC. Some of these difficulties (visual memory) were common to both offspring groups, whereas others, such as verbal learning and WM in SZoff or PSI in BDoff, were group-specific.

CONCLUSIONS

The cognitive difficulties in visual memory shown by both the SZoff and BDoff groups might point to a common endophenotype in the two disorders. Difficulties in other cognitive functions would be specific depending on the family diagnosis.

Auditory Vigilance and Working Memory in Youth at Familial Risk for Schizophrenia or Affective Psychosis in the Harvard Adolescent Family High Risk Study

BACKGROUND

The degree of overlap between schizophrenia (SCZ) and affective psychosis (AFF) has been a recurring question since Kraepelin's subdivision of the major psychoses. Studying nonpsychotic relatives allows a comparison of disorder-associated phenotypes, without potential confounds that can obscure distinctive features of the disorder. Because attention and working memory have been proposed as potential endophenotypes for SCZ and AFF, we compared these cognitive features in individuals at familial high-risk (FHR) for the disorders.

METHODS

Young, unmedicated, first-degree relatives (ages, 13-25 years) at FHR-SCZ (n=41) and FHR-AFF (n=24) and community controls (CCs, n=54) were tested using attention and working memory versions of the Auditory Continuous Performance Test. To determine if schizotypal traits or current psychopathology accounted for cognitive deficits, we evaluated psychosis proneness using three Chapman Scales, Revised Physical Anhedonia, Perceptual Aberration, and Magical Ideation, and assessed psychopathology using the Hopkins Symptom Checklist -90 Revised.

RESULTS

Compared to controls, the FHR-AFF sample was significantly impaired in auditory vigilance, while the FHR-SCZ sample was significantly worse in working memory. Both FHR groups showed significantly higher levels of physical anhedonia and some psychopathological dimensions than controls. Adjusting for physical anhedonia, phobic anxiety, depression, psychoticism, and obsessive-compulsive symptoms eliminated the FHR-AFF vigilance effects but not the working memory deficits in FHR-SCZ.

CONCLUSIONS

The working memory deficit in FHR-SZ was the more robust of the cognitive impairments after accounting for psychopathological confounds and is supported as an endophenotype. Examination of larger samples of people at familial risk for different psychoses remains necessary to confirm these findings and to clarify the role of vigilance in FHR-AFF. (JINS, 2016, 22, 1026-1037).

Gestational length affects neurocognition in early-onset schizophrenia

Obstetric complications (OC) have been linked to an increased risk for schizophrenia in offspring, especially in early-onset schizophrenia (EOS). Extensive cognitive deficits occur in EOS, although no study has yet to investigate the relationship between OC and cognition in EOS. This study aims to examine the frequency of OC in EOS compared to controls, and also investigates the relationship between OC and neurocognitive dysfunction in the two groups. Nineteen EOS patients and 53 healthy controls were tested with the MATRICS Consensus Cognitive Battery (MCCB), and the cognitive measures were combined with OC data from the Norwegian Birth Registry. The results indicated no group differences in OC in EOS and healthy controls, but a shorter gestational length in the EOS group led to significant decreases in the overall neurocognitive composite score, and in processing speed. This suggests that the poorer neuropsychological performances commonly found in EOS may be partly attributable to the length of gestation. The worsened neurocognitive functioning did not appear among controls, so gestational length had a different impact on the two groups. Our findings indicated that a shorter gestational length did not increase the risk for developing EOS, but did significantly affect the cognitive difficulties in this group.

Cognitive functioning in individuals at ultra-high risk for psychosis, first-degree relatives of patients with psychosis and patients with first-episode schizophrenia

OBJECTIVE

The aim of the present study was to investigate and compare cognitive functioning of first-degree relatives of people with schizophrenia who were also at ultra-high risk (UHR) for psychosis with patients with first-episode (FE) schizophrenia, first degree relatives of patients not fulfilling UHR criteria (FDR), and healthy control (HC) subjects.

METHOD

Forty subjects in each group were included, underwent a face-to-face interview and completed a neurocognitive test battery, including the Trail Making Test-A (TMT-A, psychomotor functions), Stroop Color Word Test (attention), Digit Symbol Coding Test (DST, processing speed and working memory) and Hopkins Verbal Leaning Test-Revised (HVLT-R, verbal memory).

RESULTS

Functioning in all the cognitive test domains displayed a gradual decrease from the HC, FDR, UHR to FE groups. After controlling for covariates, there were still significant differences in TMT-A (F(7160)=35.4, P<0.001), DST (F(7160)=38.9, P<0.001), Stroop Color Word Test (F(7160)=35.0, P<0.001), Stroop Word Test (F(7160)=36.2, P<0.001), Stroop Color Test (F(7160)=40.9, P<0.001) and HVLT-R (F(7160)=62.5, P<0.001) between the four groups, indicating that the cognitive functioning in the UHR group was intermediate between the FE and FDR groups, while the FDR group had poorer performance than the HC group, and the FE group had the poorest cognitive functioning across all four examined domains.

CONCLUSION

The results indicate that impairments in processing speed, attention, working memory and verbal memory exist in both UHR and FDR subjects. In order to clarify the associations between cognitive functioning and UHR and schizophrenia, longitudinal studies are warranted.

Research Review: Do motor deficits during development represent an endophenotype for schizophrenia? A meta-analysis

BACKGROUND

Early detection of schizophrenia risk is a critical goal in the field. Endophenotypes in children to relatives of affected individuals may contribute to this early detection. One of the lowest cost and longest theorized domains is motor development in children.

METHODS

A meta-analysis was conducted comparing individuals ≤21 years old with affected first-degree relatives (FDR) with (1) individuals from unaffected families (controls), or (2) individuals with FDR having other psychiatric disorders. Studies were classified by motor outcome and separate meta-analyses were performed across six correlated domains, with available N varying by domain.

RESULTS

Inclusion criteria were met by k = 23 independent studies with a total N = 18,582, and N across domains varying from 167 to 8619. The youth from affected families had delays in gross and fine motor development in infancy (k = 3, n = 167, Hedges'g = 0.644, confidence intervals (CI) = [0.328, 0.960], p < .001), walking milestones (k = 3, n = 608, g = 0.444, CI = [0.108, 0.780], p = .01), coordination (k = 8, n = 8619, g = 0.625, CI = [0.453, 0.797], p < .0001), and had more abnormal movements such as involuntary movements (k = 6, n = 8365, g = 0.291, CI = [0.041, 0.542], p = .02) compared with controls. However, not all effects survived correction for publication bias. Effects for neurological soft signs were small and not reliably different from zero (k = 4, n = 548, g = 0.238, CI = [-0.106, 0.583], p = .18). When comparing the FDR group to youth from families with other psychiatric disorders, the FDR group was distinguished by poorer gross and fine motor skills (k = 2, n = 275, g = 0.847, CI = [0.393, 1.300], p < .001).

CONCLUSIONS

Motor deficits during development likely represent an endophenotype for schizophrenia, although its specificity is limited in relation to other serious mental disorders. It holds promise as a low cost domain for early risk detection, although it will have to be combined with other indicators to achieve clinically usable prediction accuracy. Impaired coordination was the most robust result with a moderate effect size and lack of heterogeneity and publication bias.

Alterations of lateral temporal cortical gray matter and facial memory as vulnerability indicators for schizophrenia: An MRI study in youth at familial high-risk for schizophrenia

BACKGROUND

Structural alterations of the lateral temporal cortex (LTC) in association with memory impairments have been reported in schizophrenia. This study investigated whether alterations of LTC structure were linked with impaired facial and/or verbal memory in young first-degree relatives of people with schizophrenia and, thus, may be indicators of vulnerability to the illness.

METHODS

Subjects included 27 non-psychotic, first-degree relatives of schizophrenia patients, and 48 healthy controls, between the ages of 13 and 28. Participants underwent high-resolution magnetic resonance imaging (MRI) at 1.5Tesla. The LTC was parcellated into superior temporal gyrus, middle temporal gyrus, inferior temporal gyrus, and temporal pole. Total cerebral and LTC volumes were measured using semi-automated morphometry. The Wechsler Memory Scale - Third Edition and the Children's Memory Scale - Third Edition assessed facial and verbal memory. General linear models tested for associations among LTC subregion volumes, familial risk and memory.

RESULTS

Compared with controls, relatives had significantly smaller bilateral middle temporal gyri. Moreover, right middle temporal gyral volume showed a significant positive association with delayed facial memory in relatives.

CONCLUSION

These results support the hypothesis that smaller middle temporal gyri are related to the genetic liability to schizophrenia and may be linked with reduced facial memory in persons at genetic risk for the illness. The findings add to the growing evidence that children at risk for schizophrenia on the basis of positive family history have cortical and subcortical structural brain abnormalities well before psychotic illness occurs.

Impaired motor performance in adolescents at familial high-risk for schizophrenia

BACKGROUND

The Harvard Adolescent Family High Risk (FHR) Study examined multiple domains of function in young relatives of individuals diagnosed with schizophrenia to identify precursors of the illness. One such area is motor performance, which is deviant in people with schizophrenia and in children at risk for schizophrenia, usually offspring. The present study assessed accuracy of motor performance and degree of lateralization in FHR adolescents and young adults.

METHODS

Subjects were 33 non-psychotic, first-degree relatives of individuals diagnosed with schizophrenia, and 30 non-psychotic comparison subjects (NpC), ranging in age from 13 to 25 who were compared using a line-drawing task.

RESULTS

FHR individuals exhibited less precise and coordinated line drawing but greater degree of lateralization than controls. Performance on the linedrawing task was correlated with degree of genetic loading, a possible predictor of higher risk for schizophrenia in the pedigree.

CONCLUSIONS

The observation of increased motor deviance and increased lateralization in FHR can be utilized in identification and initiation of the treatment in those at high risk in order to prevent or delay the full manifestation of this devastating condition. The use of a rigorously quantified measure is likely to add to the sensitivity of measuring motor performance, especially when impairments may be subtle.

Cognition and Social Cognition in non-psychotic siblings of patients with schizophrenia

INTRODUCTION

Deficits in Social Cognition are common in people with schizophrenia. However, it is not clear if these deficits are a vulnerability marker and whether they are independent to cognitive difficulties. This study investigates these two issues in individuals with a genetic liability to psychosis.

METHODS

Twenty-one healthy siblings of patients with schizophrenia were compared with 21 healthy individuals on a range of cognitive and social cognitive measures. Significant differences in cognitive domains were controlled for when comparing the two groups on measures of social cognition.

RESULTS

Siblings of people with schizophrenia performed significantly worst on tests of theory of mind and social perception but not on affect recognition. Scores on tests of executive function, processing speed and general IQ were also lower in the sibling group. When controlled for differences in cognitive tests, the two groups still retained significant differences in theory of mind and social perception. However, executive function significantly contributed to theory of mind and processing speed to social perception differences.

CONCLUSIONS

These results further suggest that difficulties in some domains of social cognition are associated with a genetic vulnerability for schizophrenia. In these areas, cognitive difficulties account only partially for social cognition problems suggesting that these two domains may represent relatively independent liability factors.

Childhood abuse and neglect may induce deficits in cognitive precursors of psychosis in high-risk children

BACKGROUND

Millions of children are born to parents affected by major psychoses. Cognitive dysfunctions seen in patients are already detectable in these children. In parallel, childhood maltreatment increases the risk of adult psychoses through unknown mechanisms. We investigated whether high-risk offspring exposed to abuse/neglect displayed more cognitive precursors of adult psychoses in childhood and adolescence than nonexposed offspring.

METHODS

We used a stepwise selection strategy from a 25-year follow-up of 48 densely affected kindreds including 1500 adults (405 patients with schizophrenia or bipolar disorder) to select high-risk offspring aged 6-22 years for inclusion in our study. All offspring were assessed for childhood trauma from direct interviews with the offspring, parents and relatives and from the review of lifetime medical records of parents and children and administered a neuropsychological battery including IQ and 4 of the most impaired neuropsychological domains in psychoses.

RESULTS

Our study included 66 high-risk offspring. Those who were exposed to abuse/neglect had significantly lower IQ (effect size [ES] = 0.61) than nonexposed offspring and displayed poorer cognitive performance in visual episodic memory (ES = 0.67) and in executive functions of initiation (ES = 1.01). Moreover, exposed offspring presented more combinations of cognitive deficits that were associated with lower Global Assessment of Functioning scores.

LIMITATIONS

Exposure to abuse/neglect was not assessed in the control group, thus the study could not test whether the effect of childhood maltreatment occurred only in a high-risk setting and not in the general population.

CONCLUSION

In high-risk youths, maltreatment in childhood/adolescence may negatively impact cognitive domains known to be impaired in adults with psychoses, suggesting an early mediating effect in the association between abuse/neglect and adult psychoses. This finding provides a target for future developmental and preventive research.

Endophenotypes in Schizophrenia for the Perinatal Period: Criteria for Validation

Endophenotypes are disease-associated phenotypes that are thought to reflect the neurobiological or other mechanisms that underlie the more overt symptoms of a psychiatric illness. Endophenotypes have been critical in understanding the genetics, neurobiology, and treatment of schizophrenia. Because psychiatric illnesses have multiple causes, including both genetic and nongenetic risk factors, an endophenotype linked to one of the mechanisms may be expressed more frequently than the disease itself. However, in schizophrenia research, endophenotypes have almost exclusively been studied in older adolescents or adults who have entered or passed through the age of risk for the disorder. Yet, schizophrenia is a neurodevelopmental disorder where prenatal development starts a cascade of brain changes across the lifespan. Endophenotypes have only minimally been utilized to explore the perinatal development of vulnerability. One major impediment to the development of perinatally-useful endophenotypes has been the established validity criteria. For example, the criterion that the endophenotype be more frequently present in those with disease than those without is difficult to demonstrate when there can be a decades-long period between endophenotype measurement and the age of greatest risk for onset of the disorder. This article proposes changes to the endophenotype validity criteria appropriate to perinatal research and reviews how application of these modified criteria helped identify a perinatally-usable phenotype of risk for schizophrenia, P50 sensory gating, which was then used to propose a novel perinatal primary prevention intervention.

Neurocognitive performance in family-based and case-control studies of schizophrenia

BACKGROUND

Neurocognitive deficits in schizophrenia (SZ) are established and the Consortium on the Genetics of Schizophrenia (COGS) investigated such measures as endophenotypes in family-based (COGS-1) and case-control (COGS-2) studies. By requiring family participation, family-based sampling may result in samples that vary demographically and perform better on neurocognitive measures.

METHODS

The Penn computerized neurocognitive battery (CNB) evaluates accuracy and speed of performance for several domains and was administered across sites in COGS-1 and COGS-2. Most tests were included in both studies. COGS-1 included 328 patients with SZ and 497 healthy comparison subjects (HCS) and COGS-2 included 1195 patients and 1009 HCS.

RESULTS

Demographically, COGS-1 participants were younger, more educated, with more educated parents and higher estimated IQ compared to COGS-2 participants. After controlling for demographics, the two samples produced very similar performance profiles compared to their respective controls. As expected, performance was better and with smaller effect sizes compared to controls in COGS-1 relative to COGS-2. Better performance was most pronounced for spatial processing while emotion identification had large effect sizes for both accuracy and speed in both samples. Performance was positively correlated with functioning and negatively with negative and positive symptoms in both samples, but correlations were attenuated in COGS-2, especially with positive symptoms.

CONCLUSIONS

Patients ascertained through family-based design have more favorable demographics and better performance on some neurocognitive domains. Thus, studies that use case-control ascertainment may tap into populations with more severe forms of illness that are exposed to less favorable factors compared to those ascertained with family-based designs.

Resting-state theta-band connectivity and verbal memory in schizophrenia and in the high-risk state

BACKGROUND

Disturbed functional connectivity is assumed to underlie neurocognitive deficits in patients with schizophrenia. As neurocognitive deficits are already present in the high-risk state, identification of the neural networks involved in this core feature of schizophrenia is essential to our understanding of the disorder. Resting-state studies enable such investigations, while at the same time avoiding the known confounder of impaired task performance in patients. The aim of the present study was to investigate EEG resting-state connectivity in high-risk individuals (HR) compared to first episode patients with schizophrenia (SZ) and to healthy controls (HC), and its association with cognitive deficits.

METHODS

64-channel resting-state EEG recordings (eyes closed) were obtained for 28 HR, 19 stable SZ, and 23 HC, matched for age, education, and parental education. The imaginary coherence-based multivariate interaction measure (MIM) was used as a measure of connectivity across 80 cortical regions and six frequency bands. Mean connectivity at each region was compared across groups using the non-parametric randomization approach. Additionally, the network-based statistic was applied to identify affected networks in patients.

RESULTS

SZ displayed increased theta-band resting-state MIM connectivity across midline, sensorimotor, orbitofrontal regions and the left temporoparietal junction. HR displayed intermediate theta-band connectivity patterns that did not differ from either SZ or HC. Mean theta-band connectivity within the above network partially mediated verbal memory deficits in SZ and HR.

CONCLUSIONS

Aberrant theta-band connectivity may represent a trait characteristic of schizophrenia associated with neurocognitive deficits. As such, it might constitute a promising target for novel treatment applications.

Medial temporal lobe default mode functioning and hippocampal structure as vulnerability indicators for schizophrenia: a MRI study of non-psychotic adolescent first-degree relatives

BACKGROUND

Clues to the etiology and pathophysiology of schizophrenia can be examined in their first-degree relatives because they are genetically related to an ill family member, and have few confounds like medications. Brain abnormalities observed in young relatives are neurobiological indicators of vulnerability to illness. We examined the hypothesis that the hippocampus and parahippocampus are structurally abnormal and are related to default mode network (DMN) function and cognitive abnormalities in relatives of probands.

METHODS

Subjects were 27 non-psychotic, first-degree relatives of individuals diagnosed with schizophrenia, and 48 normal controls, ages 13 to 28, undergoing high-resolution magnetic resonance imaging (MRI) at 1.5 T. After structural scan acquisition a subset of subjects performed 2-back working memory (WM) and 0-back tasks during functional MRI (fMRI) alternating with rest. fMRI data were analyzed using SPM-8. Volumes of total cerebrum, hippocampus, and parahippocampal gyrus were measured using semi-automated morphometry.

RESULTS

Compared to controls, relatives had significantly smaller left hippocampi, without volumetric reduction in the parahippocampus. Relatives showed significantly less suppression of DMN activity in the left parahippocampal gyrus. Left hippocampal and posterior parahippocampal volumes were inversely and significantly associated with DMN processing (smaller volumes, less suppression) in relatives. Task suppression in parahippocampal gyrus significantly correlated with WM performance within the relatives.

CONCLUSION

Results support the hypothesis that the vulnerability to schizophrenia includes smaller hippocampi and DMN suppression deficits, and these are associated with poorer WM. Findings suggest a primary structural, neurodevelopmental, medial temporal lobe abnormality associated with altered DMN function independent of psychosis.

Ecological assessment of executive functions in adolescents genetically at high risk for schizophrenia

OBJECTIVE

This study sought to examine specific executive deficits in the real-life environment among adolescents genetically at high risk for schizophrenia and understand the role of the genetic risk, victimization and family functioning, and their interaction on the deficits.

METHODS

The study included 96 non-affected adolescent offspring and siblings of patients with schizophrenia in the high-risk group (HR) and 193 healthy adolescents in the healthy control group (HC), all aged between 9 and 20 years. All participants completed assessments of executive functions (EFs), victimization, and family functioning.

RESULTS

The multivariate analysis revealed that the HR group reported more difficulties on the Shift, Plan/Organize, and Task Completion scale than the HC group. Significant main effects were also detected for victimization level on all domains of EFs and for adaptability level on Inhibit, Working Memory, Plan, and Task Completion scales. Besides, the group×victimization level interactions were significant for Working Memory and Task Completion scales. Hierarchical regression analysis revealed that the genetic risk and victimization were predictors of executive deficits.

CONCLUSIONS

The HR group showed impaired EFs in the everyday environment. And, the genetic risk for schizophrenia and victimization may be related to executive dysfunction. Our results may provide clues about explaining the mechanisms of executive impairments in the HR group and help to identify new targets for early interventions.

Genetic liability, prenatal health, stress and family environment: risk factors in the Harvard Adolescent Family High Risk for schizophrenia study

OBJECTIVES

The familial ("genetic") high-risk (FHR) paradigm enables assessment of individuals at risk for schizophrenia based on a positive family history of schizophrenia in first-degree, biological relatives. This strategy presumes genetic transmission of abnormal traits given high heritability of the illness. It is plausible, however, that adverse environmental factors are also transmitted in these families. Few studies have evaluated both biological and environmental factors within a FHR study of adolescents.

METHODS

We conceptualize four precursors to psychosis pathogenesis: two biological (genetic predisposition, prenatal health issues (PHIs)) and two environmental (family environment, stressful life events (SLEs)). Participants assessed between 1998 and 2007 (ages 13-25) included 40 (20F/20M) adolescents at FHR for schizophrenia (FHRs) and 55 (31F/24M) community controls. 'Genetic load' indexed number of affected family members relative to pedigree size.

RESULTS

PHI was significantly greater among FHRs, and family cohesion and expressiveness were less (and family conflict was higher) among FHRs; however, groups did not significantly differ in SLE indices. Among FHRs, genetic liability was significantly associated with PHI and family expressiveness.

CONCLUSIONS

Prenatal and family environmental disruptions are elevated in families with a first-degree relative with schizophrenia. Findings support our proposed 'polygenic neurodevelopmental diathesis-stress model' whereby psychosis susceptibility (and resilience) involves the independent and synergistic confluence of (temporally-sensitive) biological and environmental factors across development. Recognition of biological and social environmental influences across critical developmental periods points to key issues relevant for enhanced identification of psychosis susceptibility, facilitation of more precise models of illness risk, and development of novel prevention strategies.

Cognitive deficits in youth with familial and clinical high risk to psychosis: a systematic review and meta-analysis

OBJECTIVE

It is likely that cognitive deficits are vulnerability markers for developing schizophrenia, as these deficits are already well-established findings in first-episode psychosis. Studies at-risk adolescents and young adults are likely to provide information about cognitive deficits that predate the onset of the illness.

METHOD

We conducted meta-analyses of studies comparing familial-high risk (FHR) or ultra-high risk (UHR; n = 2113) and healthy controls (n = 1748) in youth studies in which the mean age was between 15 and 29.

RESULTS

Compared with controls, high risk subjects were impaired in each domain in both UHR (d = 0.34-0.71) and FHR (d = 0.24-0.81). Heterogeneity of effect sizes across studies was modest, increasing confidence to the findings of the current meta-analysis (I(2) = 0-0.18%). In both risk paradigms, co-occurrence of genetic risk with attenuated symptoms was associated with more severe cognitive dysfunction. In UHR, later transition to psychosis was associated with more severe cognitive deficits in all domains (d = 0.31-0.49) except sustained attention. However, cognitive impairment has a limited capacity to predict the outcome of high-risk patients.

CONCLUSION

Cognitive deficits are already evident in adolescents and young adults who have familial or clinical risk for psychosis. Longitudinal developmental studies are important to reveal timing and trajectory of emergence of such deficits.

Relative stability of neurocognitive deficits in early onset schizophrenia spectrum patients

In contrast to the findings of progressive structural brain changes in adolescence, longitudinal studies of patients with early onset schizophrenia spectrum disorders (EOS) indicate that neurocognitive deficits are relatively stable over the first years. The aim of this study is to assess neurocognitive functions longitudinally in patients with EOS compared to healthy controls (HC) using the MATRICS Cognitive Consensus Battery (MCCB).

METHODS

Twenty patients with EOS and 41 HC were tested with the MCCB at baseline (T1) and after one (T2) and two years (T3). The mean age for the EOS group was 15.6 (SD=1.8) years, while the mean duration of illness was 1.7 (SD=1.4) years at T1.

RESULTS

The EOS group's neurocognitive performances indicate a stable deficit on most measures. Both the EOS and HC groups showed improved neurocognitive functioning over time on all measures except for the verbal learning domain. There was an interaction between the EOS and HC groups' performance over time on the Trail Making Test A (TMA), a subtest on the processing speed domain.

CONCLUSION

The longitudinal neurocognitive performances measured by the MCCB confirm previous findings of stable deficits in patients with EOS. It is premature to conclude whether the increases in neurocognitive performance reflect developmental processes in adolescence or may be explained by learning effects, or both. As opposed to the other tests in this domain, a stagnation in processing speed as measured by the TMA suggests that the TMA is a particularly sensitive measure of neurodevelopmental deviance in EOS.

Brain plasticity-based therapeutics

The primary objective of this review article is to summarize how the neuroscience of brain plasticity, exploiting new findings in fundamental, integrative and cognitive neuroscience, is changing the therapeutic landscape for professional communities addressing brain-based disorders and disease. After considering the neurological bases of training-driven neuroplasticity, we shall describe how this neuroscience-guided perspective distinguishes this new approach from (a) the more-behavioral, traditional clinical strategies of professional therapy practitioners, and (b) an even more widely applied pharmaceutical treatment model for neurological and psychiatric treatment domains. With that background, we shall argue that neuroplasticity-based treatments will be an important part of future best-treatment practices in neurological and psychiatric medicine.

Predictors of cognition in first episode psychosis

PURPOSE

Cognitive deficits are common in the first episode of psychosis (FEP) and may begin much earlier. While some evidence suggests that the decline in cognition occurs over the untreated symptomatic period, including the prodromal phase, others point to these deficits being present even earlier. We aimed to investigate the differential effect of untreated symptomatic and pre-morbid phases on cognition in a large sample of FEP.

METHODS

Two hundred and sixty eight FEP patients, admitted into a specialized early intervention service, were administered neuro-cognitive tests. The Circumstances of Onset and Relapse Schedule (CORS) was administered for measurement of duration of untreated psychosis (DUP), the duration of untreated illness (DUI) and demographic factors. The Pre-morbid Adjustment Scale (PAS) was used to measure different domains of pre-morbid adjustment. Seventy three healthy controls were also recruited for neuro-cognitive comparison.

RESULTS

We observed no effect of DUP and a minimal effect of DUI on cognitive functioning in FEP. Instead, the early educational pre-morbid adjustment domain was most strongly associated with cognition and predicted both global cognitive and verbal memory outcome in FEP.

CONCLUSION

Our results suggest that symptoms associated with the symptomatic phase of a FEP do not influence cognitive functioning in FEP. Instead, cognitive deficits in FEP may predate illness onset and may indicate susceptibility to such illness.