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 an n-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 (⌬ connectivity lFPN-rFPN) predicted interindividual differences in task performance more accurately than other fMRI and PET imaging measures. ⌬ 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 ⌬ 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 amphetamineinduced dopamine release capacity.
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
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.
In medicine, language, such as “history” of present illness and “chief complaints,” is used to understand patients' experience. Language is a rich source of data by which physicians make inferences, build therapeutic alliances, document formulations in the electronic health record, and care for patients. In psychiatry, language is the main source of data as there are no objective laboratory tests for diagnosis of psychiatric illness. It is also a therapeutic tool in psychotherapy. There now exist computer-based automated approaches to language analysis that can serve as tools for diagnosis, documentation, and treatment. Here, we review the history of natural language processing and provide examples of its use in psychiatry, such as psychosis prediction and detection of intoxication, and in extraction of information from psychiatric portions of the electronic health record. We also review future directions for studying discourse (and turn-taking), and potential applications of automated analysis to concurrent modes of communication, including prosody, pauses, face expression, and gesture. [ Psychiatr Ann. 2019;49(5):202–208.]
(HC) participants aged 12-35 (average = 19.0 ± 4.5 years). Linear and nonlinear curves were fit to relationships between social cognitive variables and age. Differences in age effects between CHR and HC were modeled as interaction terms. Duration of a prodromal syndrome prior to baseline and medication history were tested for interactions with age effects. Results: Emotion perception and social perception age trajectories did not differ by group. Theory of mind age trajectory, particularly for sarcasm items, had a lower slope for CHR than HC. CHR diverged from HC from mid-adolescence onward (starting to differ between approximately ages 15 and 17.5), with a minimum observation window of 4 years required to detect correlations with age. Age trajectory for theory of mind was unrelated to the presence or duration of a prior prodromal syndrome but did interact with medication history, wherein participants with an antipsychotic or antidepressant medication history did not differ from HCs. Only antipsychotic-and antidepressant-naive CHR participants showed a smaller slope for theory of mind, with differences from HC increasing with advanced age. Conclusion: In the current study, all social cognitive abilities increased during adolescence, but development of theory of mind appeared blunted for CHR participants starting in mid-adolescence. This difference, however, was only true for participants without an antipsychotic or antidepressant medication history, which could suggest benefits of early treatment or subgroups within CHR for whom social cognition is affected differently. These cross-sectional results require longitudinal replication and further inquiry into the relationships between treatment history and social cognitive development. Current results suggest that factors related to risk for psychosis may moderate adolescent social development, and that interventions targeting social cognition may be particularly helpful at this stage. Background: Clinical criteria for Ultra-High Risk of psychosis (UHR) show moderate specificity for the prediction of the first psychotic episode (FEP), with an average true positive rate of approximately 30% at 3 years. We have recently developed a multimodal probabilistic model using the odds ratio form of Bayes' rule that achieved sensitivity=73% and specificity=96% for FEP combining clinical data and biological data in a small sample of UHR patients. To validate this approach, we built a similar model using cognitive and clinical data from the Personal Assessment and Crisis Evaluation ("PACE 400") study. Methods: 430 UHR patients presenting to a specialist psychosis service in metropolitan Melbourne, Australia, were identified using the Comprehensive Assessment of At-Risk Mental State (CAARMS). Transition to FEP occurred in 114 within 13 years of presentation. Demographic and clinical data were available for the full cohort and cognitive data for 258 cases. Positive and negative likelihood ratios (LRs) for FEP were calculated for clinical and cognitive variables with statistically...
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