More severe impairment of manual dexterity in bipolar disorder compared to unipolar major depression.
ABSTRACT Mood disorders are associated with various neurocognitive deficits. However, few studies have reported the impairment of motor dexterity in unipolar depression and bipolar disorder. In the present study, manual dexterity was compared between unipolar major depression, bipolar disorder, and healthy controls.
Manual dexterity was assessed by the Purdue pegboard test in 98 patients with unipolar major depression, 48 euthymic or depressed patients with bipolar disorder, and 158 healthy controls, matched for age and gender.
Compared to healthy controls, sum of the scores of right, left, and both hands subtests (R+L+B) was significantly lower in both patients with unipolar depression and bipolar disorder (P=0.0034 and P<0.0001, respectively). Furthermore, R+L+B was significantly lower in bipolar disorder compared to unipolar depression (P=0.0016). Lithium dose and chlorpromazine equivalent dose of antipsychotics were significantly negatively correlated with some of the subtest scores. On the other hand, depression severity did not significantly correlate with any of the subtest scores. Difference in R+L+B between unipolar depression and bipolar disorder remained statistically significant even after controlling for gender, age, lithium dose, and chlorpromazine equivalent dose (P=0.0028). Limitations Bipolar patients during manic episode were not included in the study.
Gross movement dexterity was impaired in both patients with unipolar depression and bipolar disorder. The severity of impairment was significantly greater in patients with bipolar disorder. The functional difference between unipolar and bipolar patients may suggest different pathological conditions between the two depressive disorders.
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ABSTRACT: To identify changes in brain activation patterns in bipolar disorder (BD) and unipolar depression (UD) patients. Resting-state fMRI scans of 16 healthy controls, 17 BD and 16 UD patients were obtained. T-test of normalized regional homogeneity (ReHo) was performed in a voxel-by-voxel manner. A combined threshold of á = 0.05, minimum cluster volume of V = 10503 mm(3) (389 voxels) were used to determine ReHo differences between groups. In UD group, fMRI revealed ReHo increases in the left middle occipital lobe, right inferior parietal lobule, right precuneus and left convolution; and ReHo decreases in the left parahippocampalgyrus, right precentralgyrus, left postcentralgyrus, left precentralgyrus and left cingulated. In BD group, ReHo increases in the right insular cortex, left middle frontal gyrus, left precuneus, left occipital lobe, left parietal, left superior frontal gyrus and left thalamus; and ReHo decreases in the right anterior lobe of cerebellum, pons, right precentralgyrus, left postcentralgyrus, left inferior frontal gyrus, and right cingulate. There were some overlaps in ReHo profiles between UD and BD groups, but a marked difference was seen in the thalamus of BD. The resting-state fMRI and ReHo mapping are a promising tool to assist the detection of functional deficits and distinguish clinical and pathophysiological signs of BD and UD.PLoS ONE 01/2013; 8(12):e79999. · 3.53 Impact Factor
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ABSTRACT: Background Genetic variants within the ankyrin 3 gene (ANK3) have been identified as a risk factor for bipolar disorder. ANK3 influences action potential generation by clustering sodium gated channels and plays an integral role in neurotransmission. Thus, this gene may influence cognition, a process compromised in bipolar disorder. We investigated whether genetic variants of ANK3 would be associated with an array of cognitive functions in patients with bipolar disorder and healthy individuals. Methods In a sample of 49 patients with bipolar disorder and 633 healthy subjects, we examined possible effects of 2 risk variants within ANK3, rs10994336 and rs10761482, on 7 neurocognitive domains. Results Compared to healthy subjects, patients with bipolar disorder demonstrated significantly poorer performance on most of the cognitive domains examined. The risk C-allele of rs10761482 was significantly associated with worse performance on verbal comprehension, logical memory and processing speed in patients. This allele was significantly associated with worse performance on executive function and visual memory in healthy individuals. No significant association was observed between rs10994336 and cognition either in patients or healthy individuals. Limitations The sample size of patients with bipolar disorder was small, and most of the patients were on psychotropic medication. Conclusions These results indicate that a risk variant within ANK3 may have an impact on neurocognitive function, suggesting a mechanism by which ANK3 confers risk for bipolar disorder.Journal of affective disorders 01/2014; 158:90–96. · 3.76 Impact Factor
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ABSTRACT: We hypothesized that motor retardation in bipolar depression is mediated by disruption of the pre-executive stages of motor production. We used functional magnetic resonance imaging to investigate neural activity during motor imagery and motor execution to elucidate whether brain regions that mediate planning, preparation, and control of movement are activated differently in subjects with bipolar depression (n = 9) compared with healthy controls (n = 12). We found significant between-group differences. During motor imagery, the patients activated the posterior medial parietal cortex, the posterior cingulate cortex, the premotor cortex, the prefrontal cortex, and the frontal poles more than the controls did. Activation in the brain areas involved in motor selection, planning, and preparation was altered. In addition, limbic and prefrontal regions associated with self-reference and the default mode network were altered during motor imagery in bipolar depression with motor retardation.The Journal of nervous and mental disease 10/2013; 201(10):885-893. · 1.77 Impact Factor