Apathy Is Associated With Ventral Striatum Volume in Schizophrenia Spectrum Disorder.

Apathy is prevalent in schizophrenia, but its etiology has received little investigation. The ventral striatum (VS), a key brain region involved in motivated behavior, has been implicated in studies of apathy. We therefore evaluated whether apathy is associated with volume of the VS on MRI in 23 patients with schizophrenia using voxel-based morphometry. Results indicated that greater self-reported apathy severity was associated with smaller volume of the right VS even when controlling for age, gender, depression, and total gray matter volume. The finding suggests that apathy is related to abnormality of brain circuitry subserving motivated behavior in patients with schizophrenia.

Performance on the Cognitive Estimation Test in schizophrenia.

The Cognitive Estimation Test (CET) is generally considered to be a measure of executive function, but there is little information with respect to its clinical utility in patients with schizophrenia. In the present investigation, we evaluated the clinical utility of the CET in 42 patients with schizophrenia relative to 42 healthy comparison subjects matched for age, gender, and parental education. Construct validity of the CET was examined though correlation with other tests of executive and nonexecutive cognitive functions. Patients with schizophrenia performed more poorly on the CET compared with the healthy comparison group, which could not be accounted for by greater level of depression in the patient sample. In the schizophrenia group, CET was correlated with measures of executive function but also general intellectual functioning, verbal learning, and auditory attention. CET performance was not associated with depression or overall severity of psychopathology in the patient sample. These findings provide support for the clinical utility of the CET in schizophrenia but indicate that both executive and nonexecutive cognitive functions contribute to performance on the measure. Thus, the integrity of other cognitive processes should be taken into consideration when interpreting the presence of a deficit in cognitive estimation in patients with schizophrenia.

Inferential-reasoning impairment in schizophrenia-spectrum disorders.

The performance of 15 participants with schizophrenia-spectrum disorders (SCZ) on an inferential-reasoning task was compared with that of 15 healthy-control participants (HC). The SCZ group showed poorer inferential reasoning than HCs, independent of their negative or positive symptoms. These findings are consistent with previous research showing deficits of reasoning in schizophrenia, and indicate that this deficit is independent of severity of delusions.

Regional gray matter correlates of perceived emotional intelligence.

Coping with stressful life events requires a degree of skill in the ability to attend to, comprehend, label, communicate and regulate emotions. Individuals vary in the extent to which these skills are developed, with the term 'alexithymia' often applied in the clinical and personality literature to those individuals most compromised in these skills. Although a frontal lobe model of alexithymia is emerging, it is unclear whether such a model satisfactorily reflects brain-related patterns associated with perceived emotional intelligence at the facet level. To determine whether these trait meta-mood facets (ability to attend to, have clarity of and repair emotions) have unique gray matter volume correlates, a voxel-based morphometry study was conducted in 30 healthy adults using the Trait Meta Mood Scale while co-varying for potentially confounding sociodemographic variables. Poorer Attention to Emotion was associated with lower gray matter volume in clusters distributed primarily throughout the frontal lobe, with peak correlation in the left medial frontal gyrus. Poorer Mood Repair was related to lower gray matter volume in three clusters in frontal and inferior parietal areas, with peak correlation in the left anterior cingulate. No significant volumetric correlations emerged for the Clarity of Emotion facet. We discuss the localization of these areas in the context of cortical circuits known to be involved in processes of self-reflection and cognitive control.

Subjective rating of working memory is associated with frontal lobe volume in schizophrenia.

BACKGROUND: Patients with schizophrenia commonly show deficits in working memory on objective neuropsychological measures, and brain imaging studies have documented neural abnormalities during performance of working memory tasks. It remains unclear to what extent such patients are able to accurately gauge the integrity of their working memory in their daily lives. AIMS: We evaluated the relationship between subjective rating of working memory integrity in daily life and volumes of the frontal, temporal, and parietal lobes in patients with schizophrenia. METHODS: Participants included 29 patients with schizophrenia and 26 healthy comparison subjects. Participants completed a structural magnetic resonance imaging (MRI) scan, the Self Report form of the Behavioral Rating Inventory of Executive Function - Adult version (BRIEF-A), and Digit Span Backwards as an objective measure of working memory. Lobar volumes were obtained using an automated processing package and adjusted for total intracranial volume. RESULTS: The patient group reported worse working memory in daily life, and performed worse on Digit Span Backwards, than the comparison group. Within the patient group, poorer working memory in daily life was associated with smaller left and right frontal lobe volumes. Shorter backwards digit span was associated with smaller left frontal and left and right temporal lobe volumes. CONCLUSIONS: The significant relationship between frontal lobe volumes and subjective working memory in daily life provides some support for the validity of self report measures of cognitive functioning in patients with schizophrenia, and provides further evidence for a contribution of frontal lobe abnormality to executive dysfunction in the illness.