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Characterizing the anatomical substrates of major brain functions such as cognition and emotion is of utmost importance to the ongoing efforts of understanding the nature of psychiatric ailments and their potential treatment. The aim of our study was to investigate how the brain handles affective and cognitive interferences on cognitive processes. Functional magnetic resonance imaging investigation was performed on healthy individuals, comparing the brain oxygenation level dependent activation patterns during affective and cognitive counting Stroop tasks. The affective Stroop task activated rostral parts of medial prefrontal cortex (PFC) and rostral and ventral parts of lateral PFC, while cognitive Stroop activated caudal parts of medial PFC and caudal and dorsal parts of lateral PFC. Our findings suggest that the brain may handle affective and cognitive interference on cognitive processes differentially, with affective interference preferentially activating rostral and ventral PFC networks and cognitive interference activating caudal and dorsal PFC networks. [ABSTRACT FROM AUTHOR]

The caudate nucleus is a structure implicated in the neural circuitry of psychological responses to trauma. This study aimed to quantify the volume of the caudate in persons exposed to trauma. Thirty-six subjects under 65 were recruited from transport workers in Stockholm who reported having been unintentionally responsible for a person-under-the-train accident or among employees having experienced an assault in their work (1999-2001) between 3 months and 6 years before MRI scanning. In those exposed to the trauma, a DSM-IV diagnosis of post-traumatic stress disorder (PTSD) was made by an independent psychiatrist, with subjects being classified as PTSD or no PTSD. MRI data were analyzed blindly to all clinical information by an experienced rater using a standardized manual tracing protocol to quantify the volume of the caudate. Within-group comparisons of PTSD (n=19) and no PTSD (n=17) found the right caudate nucleus to be significantly (9%) larger than the left: a right hemisphere baseline asymmetry. A multivariate analysis of covariance (MANCOVA) was conducted to assess the volume of the caudate nucleus (right and left) in relation to the diagnosis of no PTSD (n=17) or PTSD (n=19). After adjustment for the covariates (age, sex, intracranial volume, years since trauma, and number of trauma episodes), there was a significant difference in raw right caudate nucleus volume between subjects with PTSD compared with those without PTSD. Volume of the left caudate nucleus was not significantly different between the PTSD and no PTSD groups. The right caudate volume in the PTSD group was 9% greater compared with the no PTSD group. There is a larger right hemisphere volume of the caudate within those exposed to trauma with active PTSD compared with those without PTSD, superimposed upon a baseline caudate asymmetry.

Most rating scales for affective disorders measure either depressive or hypomanic/manic symptoms and there are few scales for hypomania/mania in a self-rating format. We wanted to develop and validate a self-rating scale for comprehensive assessment of depressive, manic/hypomanic and mixed affective states. We developed an 18-item self-rating scale starting with the DSM-IV criteria for depression and mania, with subscales for depression and mania. The scale was evaluated on 61 patients with a diagnosis of affective disorder, predominantly bipolar disorder type I, using Montgomery-Asberg Depression Rating Scale (MADRS), Hypomania Interview Guide-Clinical version (HIGH-C) and Clinical Global Impression scale, modified for bipolar patients (CGI-BP) as reference scales. Internal consistency of the scale measured by Cronbach's alpha was 0.89 for the depression subscale and 0.91 for the mania subscale. Spearman's correlation coefficients (two-tailed) between the depression subscale and MADRS was 0.74 (P<0.01) and between mania subscale and HIGH-C 0.80 (P<0.01). A rotated factor analysis of the scale supported the separation of symptoms in the mania and depression subscale. We established that the self-rating scales sensitivity to identify mixed states, with combined cut-offs on the MADRS and HIGH-C as reference, was 0.90 with a specificity of 0.71. The study shows that the Affective Self Rating Scale is highly correlated with ratings of established interview scales for depression and mania and that it may aid the detection of mixed affective states.