The characteristics of brain function activity between patients with bipolar depression and major depressive disorder: a functional magnetic resonance imaging study of affective pictures task

Abstract

Objective To investigate the characteristics of brain function activity in patients with bipolar depressive disorder and major depressive disorder(MDD)facing affective pictures. Methods Thirty bipolar Ⅰ depressive disorder patients, 30 MDD patients and 30 healthy controls were included in the study. All subjects were scanned with 3.0T MRI scanner in negative and neutral affective pictures task state. After eliminating those taking medicines and head moving, and matching the factors such as gender, age and education level et al, there were 17 patients with bipolar Ⅰ depressive disorder, 18 patients with MDD and 21 healthy controls in the final analysis. Using SPM and REST software to complete the image preprocessing and statistical analysis of the three groups and one-way analysis of variance(ANOVA)with least significant difference(LSD)post-hoc tests were used to compare different brain regions. Meanwhile, Pearson correlation analysis was performed to further assess the relationship between the clusters of these different regions and HAMD17 score. Results Facing negative and neutral affective pictures tasks, subjects with bipolar Ⅰ depressive disorder showed lower activation in right parahippocampus(negative affective pictures MNI(x, y, z): 27,-21,-18; t=4.84; neutral affective pictures MNI(x, y, z): 21,-33,-12; t=5.33)than the healthy controls(P 0.05). Conclusion The results suggest that there are differences of brain function activity between bipolar Ⅰ depressive disorder and MDD in negative and neutral affective pictures task. Patients with bipolar Ⅰ depressive disorder showed reduced activities and MDD showed enhanced activities. These feature may be regarded as the biomarker to distinguish the bipolar Ⅰ depressive disorder from MDD. Key words: Depressive disorder; Bipolar disorder; Magnetic resonance imaging; Negative affective picture; Neutral affective picture