Comparison of self-report and clinician-rated schizotypal traits in schizotypal personality disorder and community controls.

Given the common use of self-report questionnaires to assess schizotypy in personality pathology and schizophrenia research, it is important to determine the concordance between self-report and clinician ratings. 250 individuals with schizotypal personality disorder (SPD) and 116 community controls (CTR) were assessed on schizotypal traits using a clinical interview, the Structured Interview for DSM-IV Personality disorders (SIDP), and a self-report questionnaire, the Schizotypal Personality Questionnaire (SPQ). Ordinal logistic regressions examined concordance between self-reported and clinician-rated scores in CTR and SPD separately. Analyses of variance examined how the SPQ performed on differentiating between CTR with low schizotypy, CTR with high schizotypy, and SPD. For both CTR and SPD, higher SPQ subscale scores were significantly associated with higher clinician ratings on the respective SIDP items for the Ideas of Reference, Magical Thinking, Unusual Perceptual Experience, Suspiciousness, and Social Anxiety items, but not the Odd Speech or Limited Affect items. Higher SPQ subscale scores for Odd Behavior and Lack of Close Friends were significantly associated with the clinician-rated SIDP item scores in CTR but not SPD. CTR with low schizotypy scored lower on all SPQ subscales than CTR with high schizotypy, who did not differ from SPD. Self-report ratings are concordant with clinician ratings for positive schizotypal traits, whereas certain disorganization and interpersonal traits are not, particularly for individuals with SPD. The SPQ can differentiate between high and low schizotypy controls, but not between high schizotypy controls and individuals with SPD. Assessment of schizotypal traits should include both self-report questionnaires and clinician ratings.

Self-esteem and Symptoms in Individuals at Clinical High Risk for Psychosis.

Individuals with psychotic symptoms often report low global self-esteem (GSE). However, it remains unclear whether the low GSE is linked to the presence of psychotic symptoms or it is present before the onset of psychosis. In addition, the specific subdomains of GSE in these populations are unknown. To address this question, we conducted a cross-sectional study comparing global and SE elements among individuals at clinical high risk for psychosis (CHR; n = 36), individuals with schizophrenia (SCZ; n = 43), and healthy controls (HCs; n = 40). We then examined among CHR individuals the association between GSE, subdomains, and symptoms. CHR individuals displayed significantly lower GSE compared to HCs, at a level comparable with those for individuals with SCZ. The low GSE was driven primarily by self-perceptions of work and interpersonal relationships abilities. Lower GSE was associated with overall negative and disorganized symptoms severity, but not positive ones. The authors discuss the implications of the findings to intervention development.

Dynamic Connectivity between Brain Networks Supports Working Memory: Relationships to Dopamine Release and Schizophrenia.

Connectivity between brain networks may adapt flexibly to cognitive demand, a process that could underlie adaptive behaviors and cognitive deficits, such as those observed in neuropsychiatric conditions like schizophrenia. Dopamine signaling is critical for working memory but its influence on internetwork connectivity is relatively unknown. We addressed these questions in healthy humans using functional magnetic resonance imaging (during ann-back working-memory task) and positron emission tomography using the radiotracer [(11)C]FLB457 before and after amphetamine to measure the capacity for dopamine release in extrastriatal brain regions. Brain networks were defined by spatial independent component analysis (ICA) and working-memory-load-dependent connectivity between task-relevant pairs of networks was determined via a modified psychophysiological interaction analysis. For most pairs of task-relevant networks, connectivity significantly changed as a function of working-memory load. Moreover, load-dependent changes in connectivity between left and right frontoparietal networks (Δ connectivity lFPN-rFPN) predicted interindividual differences in task performance more accurately than other fMRI and PET imaging measures. Δ Connectivity lFPN-rFPN was not related to cortical dopamine release capacity. A second study in unmedicated patients with schizophrenia showed no abnormalities in load-dependent connectivity but showed a weaker relationship between Δ connectivity lFPN-rFPN and working memory performance in patients compared with matched healthy individuals. Poor working memory performance in patients was, in contrast, related to deficient cortical dopamine release. Our findings indicate that interactions between brain networks dynamically adapt to fluctuating environmental demands. These dynamic adaptations underlie successful working memory performance in healthy individuals and are not well predicted by amphetamine-induced dopamine release capacity. SIGNIFICANCE STATEMENT: It is unclear how communication between brain networks responds to changing environmental demands during complex cognitive processes. Also, unknown in regard to these network dynamics is the role of neuromodulators, such as dopamine, and whether their dysregulation could underlie cognitive deficits in neuropsychiatric illness. We found that connectivity between brain networks changes with working-memory load and greater increases predict better working memory performance; however, it was not related to capacity for dopamine release in the cortex. Patients with schizophrenia did show dynamic internetwork connectivity; however, this was more weakly associated with successful performance in patients compared with healthy individuals. Our findings indicate that dynamic interactions between brain networks may support the type of flexible adaptations essential to goal-directed behavior.