Comparisons of verbal fluency brain correlates between adults and adolescents suffering from schizophrenia spectrum disorders: A pilot study

Background and Objectives: Prefrontal cortex (PFC) dysfunctions leading to cognitive deficits refer to a core feature of schizophrenia spectrum disorders (SSD). This exploratory study compares the effect of SSD on two stages of maturation of PFC. Methods: Using functional magnetic resonance imaging (fMRI), we measured the brain correlates related to a verbal fluency task (a hallmark executive function test) in 12 patients with SSD: 6 adolescents (SSD-ado) and 6 adults (SSD-adu). Results: SSD-ado showed greater activation in insula, thalamus and hIP1 whereas SSDadu recruited more intensively precentral gyrus and temporal pole to resolve the task. Thus, adolescents with SSD seem to adopt less frontal mediated strategic processes. In contrast, adults seem to be able to use PFC mediated strategy despite the well-known deleterious effect of SSD on the PFC. Conclusions: This first exploratory study revealed that adults and adolescents with SSD seemed not to use the same strategy to resolve a verbal fluency task. Thus, despite the illness, which is known to have a deleterious influence on PFC, adult patients seem to be able to recruit these resources to perform an executive function task. Further studies are needed in order to confirm and extend these new and preliminary results (AU)

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Increased activation in Broca's area after cognitive remediation in schizophrenia.

Functional magnetic resonance imaging (fMRI) was used to measure changes in cerebral activity in patients with schizophrenia after participation in the Cognitive Remediation Program for Schizophrenia and other related disorders (RECOS). As RECOS therapists make use of problem-solving and verbal mediation techniques, known to be beneficial in the rehabilitation of dysexecutive syndromes, we expected an increased activation of frontal areas after remediation. Executive functioning and cerebral activation during a covert verbal fluency task were measured in eight patients with schizophrenia before (T1) and after (T2) 14 weeks of RECOS therapy. The same measures were recorded in eight patients with schizophrenia who did not participate in RECOS at the same intervals of time (TAU group). Increased activation in Broca's area, as well as improvements in performance of executive/frontal tasks, was observed after cognitive training. Metacognitive techniques of verbalization are hypothesized to be the main factor underlying the brain changes observed in the present study.

A randomized controlled trial of the effectiveness of computer-assisted cognitive remediation (CACR) in adolescents with psychosis or at high risk of psychosis.

BACKGROUND: Computer assisted cognitive remediation (CACR) was demonstrated to be efficient in improving cognitive deficits in adults with psychosis. However, scarce studies explored the outcome of CACR in adolescents with psychosis or at high risk. AIMS: To investigate the effectiveness of a computer-assisted cognitive remediation (CACR) program in adolescents with psychosis or at high risk. METHOD: Intention to treat analyses included 32 adolescents who participated in a blinded 8-week randomized controlled trial of CACR treatment compared to computer games (CG). Cognitive abilities, symptoms and psychosocial functioning were assessed at baseline and posttreatment. RESULTS: Improvement in visuospatial abilities was significantly greater in the CACR group than in CG. Other cognitive functions, psychotic symptoms and psychosocial functioning improved significantly, but at similar rates, in the two groups. CONCLUSION: CACR can be successfully administered in this population; it proved to be effective over and above CG for the most intensively trained cognitive ability.

Deteriorated visual backward masking in the shine-through effect in adolescents with psychosis.

Visual backward masking is a reliable and widely used tool in schizophrenia research. Whereas many studies have shown masking deficits in adult patients, there are only very few studies with adolescents with psychosis-and with controversial results. Masking deficits of adolescents are of primary interest because they are not caused by long-term suffering from the disease and severe medication. We investigated 15 adolescents with psychosis and 19 age-matched controls in the shine-through backward masking paradigm for which strong performance deficits were shown previously in adult schizophrenic patients and their relatives. Adolescents with psychosis were strongly impaired in the shine-through effect compared to controls. This result adds further evidence that backward masking is an endophenotype of schizophrenia.

Detection of cognitive impairment with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) in adolescents with psychotic symptomatology.

Cognitive impairment has been identified in the early phase of schizophrenia spectrum disorders, and is a major contributor to disease-related disability. While screening tools assessing cognitive impairment have been validated for adult schizophrenic populations, there is a need for brief, easily administered, standardized instruments that provide clinically relevant information for adolescents. This study examines the utility of the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) in identifying and quantifying neurocognitive impairment in adolescents with schizophrenia spectrum disorders and other serious psychiatric illnesses. 112 adolescents, including 32 healthy subjects and 80 patients, were administered the RBANS. Patients with psychotic disorders demonstrated significant impairment on the RBANS total score compared to patients with other disorders and healthy controls, but this impairment appeared somewhat less severe than is typically reported for in adult patients with schizophrenia on this measure. The RBANS appears to be sensitive in the detection of neurocognitive impairment in a psychiatric population of adolescents with psychotic symptomatology, and may therefore have utility as a clinical screening instrument and/or neurocognitive outcome measure in this population.