Neuroimaging Studies of Cognitive Function in Schizophrenia.

Persons suffering from schizophrenia present cognitive impairments that have a major functional impact on their lives. Particularly, executive functions and episodic memory are consistently found to be impaired. Neuroimaging allows the investigation of affected areas of the brain associated with these impairments and, moreover, the detection of brain functioning improvements after cognitive remediation interventions. For instance, executive function impairments have been associated with prefrontal cortex volume and thickness; cognitive control impairments are correlated with an increased activation in the anterior cingulate cortex, and episodic memory impairments are linked to hippocampal reduction. Some findings suggest the presence of brain compensatory mechanisms in schizophrenia, e.g. recruiting broader cortical areas to perform identical tasks. Similarly, neuroimaging studies of cognitive remediation in schizophrenia focus differentially on structural, functional and connectivity changes. Cognitive remediation improvements have been reported in two main areas: the prefrontal and thalamic regions. It has been suggested that those changes imply a functional reorganisation of neural networks, and cognitive remediation interventions might have a neuroprotective effect. Future studies should use multimodal neuroimaging procedures and more complex theoretical models to identify, confirm and clarify these and newer outcomes. This chapter highlights neuroimaging findings in anatomical and functional brain correlates of schizophrenia, as well as its application and potential use for identifying brain changes after cognitive remediation.

Satisfaction and Needs in Serious Mental Illness and Autism Spectrum Disorder: The REHABase Psychosocial Rehabilitation Project.

OBJECTIVE: The REHABase project is a French observational, prospective, and multicenter cohort study of serious mental illness and autism spectrum disorder (ASD), launched in 2016 for a planned minimum duration of 15 years. The aim is to characterize the care and quality-of-life needs of participants. This article presents initial results from data collection. METHODS: Psychosocial, cognitive, and functional data were collected at baseline, annually, and after rehabilitation care. Data from the baseline evaluation on diagnoses, medications, well-being, insight, life satisfaction, and care needs are presented. The clinical profiles of REHABase participants with serious mental illness or ASD were assessed in relation to their level of satisfaction with life and well-being in nine life dimensions and their needs, according to their stage of recovery in a five-stage model. RESULTS: Baseline data were collected for 1,397 participants between January 2016 and August 2018. Main diagnoses were schizophrenia spectrum disorder (49%); ASD (13%); and personality (12%), bipolar (9%), and major depressive (6%) disorders. More than 50% of participants reported needs for care or interventions in four of nine dimensions: employment, cognitive functioning, symptom management, and interpersonal relationships. Nearly half of participants were not in the active stages of recovery (stages 4 and 5), and even those considered to have reached the final stage continued to require help in several areas. CONCLUSIONS: Most participants had already received psychiatric care for several years, and most remained dissatisfied with their social and emotional life and their psychological well-being.

Multi-talker background and semantic priming effect.

The reported studies have aimed to investigate whether informational masking in a multi-talker background relies on semantic interference between the background and target using an adapted semantic priming paradigm. In 3 experiments, participants were required to perform a lexical decision task on a target item embedded in backgrounds composed of 1-4 voices. These voices were Semantically Consistent (SC) voices (i.e., pronouncing words sharing semantic features with the target) or Semantically Inconsistent (SI) voices (i.e., pronouncing words semantically unrelated to each other and to the target). In the first experiment, backgrounds consisted of 1 or 2 SC voices. One and 2 SI voices were added in Experiments 2 and 3, respectively. The results showed a semantic priming effect only in the conditions where the number of SC voices was greater than the number of SI voices, suggesting that semantic priming depended on prime intelligibility and strategic processes. However, even if backgrounds were composed of 3 or 4 voices, reducing intelligibility, participants were able to recognize words from these backgrounds, although no semantic priming effect on the targets was observed. Overall this finding suggests that informational masking can occur at a semantic level if intelligibility is sufficient. Based on the Effortfulness Hypothesis, we also suggest that when there is an increased difficulty in extracting target signals (caused by a relatively high number of voices in the background), more cognitive resources were allocated to formal processes (i.e., acoustic and phonological), leading to a decrease in available resources for deeper semantic processing of background words, therefore preventing semantic priming from occurring.