Neurocognition Function of Patients With Bipolar Depression, Unipolar Depression, and Depression With Bipolarity

Abstract

Much evidence shows that some Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5)-defined unipolar depression (UD) with bipolarity manifests bipolar diathesis. Little is known about the cognitive profiles of patients with depression with bipolarity (DWB). The study aimed to investigate the differences in cognitive profiles among patients with bipolar depression (BD), major depressive disorder (namely, UD), and DWB. Drug-naïve patients with BD, UD, and DWB and healthy controls (HC) were recruited (30 cases in each group). Cognitive function was evaluated by THINC-it (THINC-intelligent tool), Wisconsin Card Sorting Test (WCST), and continuous performance test (CPT). For THINC-it, no significant differences of the Z-scores in both objective and subjective factors were found between the DWB group and BD group, but the Z-scores in the BD group were significantly lower than those in the UD group. For WCST, significant differences were found between the BD group and DWB group in the number of responses, categories completed, trails to completed first category, perseverative responses, and perseverative errors. All the indices of WCST in the DWB group were significantly worse than those in the UD group except for trails to completed first category and total number of response correct. For CPT, only scores of leakage responses and false responses in the four-digit number in the BD group and DWB group were significantly higher than those in the UD group; no significant difference was found between the BD group and DWB group. The results indicated that patients with DWB might perform differently from those with UD but similarly to those with BD with cognition impairment.

Processing speed and sustained attention in bipolar disorder and major depressive disorder: A systematic review and meta‐analysis

“…Reasons for exclusion are summarised in Table S4. After full‐text screening, 103 studies were included in the review; 101 were eligible for meta‐analysis 19,22,24,28,29,57–154 …”

THINC-Integrated Tool (THINC-it): A Brief Measurement of Changes in Cognitive Functioning and Its Correlation with the Life Quality of Patients with Schizophrenia and Related Disorders—A Pilot Study

“…In addition to its clinical application, the THINC-it tool is used commonly across research studies to measure and monitor cognitive impairment in Major Depressive Disorder—MDD [ 36 , 37 , 38 , 39 , 40 , 41 ]. Studies show the associations between cognitive deficits and global and specific psychosocial deficits in patients with current and remitted MDD [ 42 , 43 , 44 ].…”

Working memory updating in individuals with bipolar and unipolar depression: fMRI study

“…The differences in emotion processing could differentially affect the ability of individuals with BD and UD to resolve interference from emotional stimuli especially during a difficult working memory task. Considering these differences as well as the evidence for more severe cognitive deficit in BD than UD [ 22 , 41 ] and smaller difficulty-related activation changes in working memory regions in BD versus HC [ 35 ], we hypothesized that the PFC, anterior cingulate, and parietal brain regions would show smaller difficulty-related activation changes in individuals with BD versus UD and HC, especially in the presence of happy faces. However, based on the meta-analytical findings [ 37 ], we did not expect to find differences between individuals with UD and HC.…”