The frontal pole and cognitive insight in schizophrenia.

Absence of insight owing to impaired self-reflection and lack of touch with reality is a hallmark of schizophrenia. Functional imaging studies in healthy individuals have implicated the frontal pole (FP), sub-division of the prefrontal cortex in self-reflective processes. Despite the significance of self-referential processing in the pathogenesis of schizophrenia, the relationship between FP volume and cognitive insight in this disorder is underexplored. We examined the relationship between cognitive insight and volume of FP using precise manual morphometry of high resolution magnetic resonance images in 19 schizophrenia patients (SCZ) and 21 healthy-volunteers (HV). The manual morphometry technique was replicated from a previous study based on a cytoarchitectonically and functionally valid definition of FP and cognitive insight was measured using Beck's cognitive insight scale. Left frontal pole volume was a significant predictor of self-reflection sub-score of Beck's cognitive insight scale (ß=0.68; t = 2.86; p = 0.01). A significant inverse relationship between age and bilateral FP volumes was noted in HV (left FP - r=-0.45; p = 0.04; right FP - r=-0.57; p = 0.008) but not in SCZ (p>0.05). Our findings provide anatomical substrates to devise intervention strategies targeting cognitive insight, thereby improving treatment adherence and functional outcomes.

Comparison of first-episode and multiple-episode bipolar disorder: A surface-based morphometry study.

It is still unclear whether the structural abnormalities in Bipolar disorder (BD) are static or progressive. We aimed to compare differences in cortical thickness, surface area, and volume between patients with BD and healthy volunteers (HV) and to examine whether there are differences between patients who have had a single manic episode and those with multiple episodes. We recruited 30 patients with Type I BD and 30 age and sex matched HV. All participants underwent structural magnetic resonance imaging. Cortical volume, thickness, and surface area were measured using the QDEC tool from the Freesurfer software with age and intracranial volume as covariates. Study groups were comparable across age, sex distribution, and intracranial volume. Patients had significantly lower surface area in bilateral cuneus, right postcentral gyrus, and rostral middle frontal gyri; and lower cortical volume in the left middle temporal gyrus, right postcentral gyrus, and right cuneus. BD patients with multiple episodes had lower cortical measures while those with single episode had cortical measures comparable to HV. Findings indicate that the pathophysiological processes in BD are possibly progressive in nature. Our findings underscore the potential importance of early diagnosis and intervention in preventing deterioration and improving functional recovery.