Reduced gray matter volume in ventral prefrontal cortex but not amygdala in bipolar disorder: Significant effects of gender and trait anxiety

Abstract

Neuroimaging studies in bipolar disorder report gray matter volume (GMV) abnormalities in neural regions implicated in emotion regulation, including ventral/orbital medial prefrontal cortex (OMPFC) GMV decreases and, more inconsistently, amygdala GMV increases. We aimed to examine OMPFC and amygdala GMV in bipolar disorder, type 1 patients (BPI) versus healthy control participants (HC), and examine potential confounding effects of gender, clinical and illness history variables and psychotropic medication upon any group differences that were demonstrated in OMPFC and amygdala GMV. Images were acquired from 27 BPI (17 euthymic, 10 depressed) and 28 age-and gender-matched HC in a 3T Siemens scanner. Data were analyzed with SPM5 using voxel-based morphometry to first examine main effects of diagnostic group and gender upon whole brain (WB) GMV. Post hoc analyses were subsequently performed to examine the extent to which clinical and illness history variables and psychotropic medication contributed to GMV abnormalities in BPI in a priori and non-a priori regions demonstrated by the above VBM analyses. Here, SPPSS was used to examine the effects of these variables on magnitude of GMV in these a priori and nona priori regions in BPI versus HC. BPI showed reduced GMV in two regions established a priori: bilateral posteromedial rectal gyrus (PMRG), but no amygdala GMV abnormalities. BPI also showed reduced GMV in two non-a priori regions: left parahippocampal gyrus and left putamen. For left PMRG GMV, there was a significant group by gender by trait anxiety interaction. GMV was significantly reduced in male low trait anxiety BPI versus male low trait anxiety HC, and in high versus low trait anxiety male BPI. Our findings show in BPI significant effects of male gender and high trait anxiety on GMV reduction in left PMRG, part of the OMPFC medial prefrontal network implicated in visceromotor and emotion regulation.

Alzheimer´s Disease associated with Psychiatric Comorbidities

“…However, there is still some disagreement over the data pertaining to the cerebrovascular changes found between various studies, because of the different age of the patients and the regions where these changes are found (Almeida et al 2009), (Haller et al 2011), (Rej et al 2014). Further research is needed to establish the relationship between bipolar disorder and AD, and to ascertain whether these changes are directly related to the cognitive deficits found in both conditions.…”

Dopamine transporter density of striatum showed to be increased in Schizophrenia first-episode drug-naïve patients

“…Cerebral perfusion reduction in different regions that we found should be studied and compared with our different psychometrics findings, which is not the objective of this study. Alterations in the prefrontal cortex are consistently implicated in psychiatric disorders, where studies have reported decreased metabolism, morphological changes [22] and increased oxidative damage [23]. Prefrontal cortex has a high relative density of dopaminergic projections compared with other cortical regions [24], and dopamine is involved in the regulation of working memory by the prefrontal cortex [25], which is impaired in patients with schizophrenia [26,27].…”

Emotional and Motivational Processes in Bipolar Disorder: A Neural Network Perspective

“…However, other studies have found no differences in the caudate of bipolar disorder patients [107][108][109][110][111][112][113] or decreased caudate volume [114]. Similarly, putamen enlargement was reported [112,115,116], but other studies found no differences in the putamen [105,107,113] or decreased volume [117]. Studies also showed reduced volume in the nucleus accumbens [118,119].…”