Attention bias in older women with remitted depression is associated with enhanced amygdala activity and functional connectivity

Abstract

Background: Cognitive bias is a common characteristic of major depressive disorder (MDD) and is posited to remain during remission and contribute to recurrence risk. Attention bias may be related to enhanced amygdala activity or altered amygdala functional connectivity in depression. The current study examined attention bias, brain activity for emotional images, and functional connectivity in post-menopausal women with and without a history of major depression.

Methods: Attention bias for emotionally valenced images was examined in 33 postmenopausal women with (n=12) and without (n=21) a history of major depression using an emotion dot probe task during fMRI. Group differences in amygdala activity and functional connectivity were assessed using fMRI and examined for correlations to attention performance.

Results: Women with a history of MDD showed greater attentional bias for negative images and greater activity in brain areas including the amygdala for both positive and negative images (pcorr <0.001) than women without a history of MDD. In all participants, amygdala activity for negative images was correlated with attention facilitation for emotional images. Women with a history of MDD had significantly greater functional connectivity between the amygdala and hippocampal complex. In all participants amygdala-hippocampal connectivity was positively correlated with attention facilitation for negative images.

Limitations: Small sample with unbalanced groups.

Conclusions: These findings provide evidence for negative attentional bias in euthymic, remitted depressed individuals. Activity and functional connectivity in limbic and attention networks may provide a neurobiological basis for continued cognitive bias in remitted depression.

Keywords: Attention; Brain imaging/neuroimaging; Cognition; Depression; Functional MRI.

Figure 1

Emotion Dot Probe (EDP) Task

Figure 2. EDP Performance and Amygdala Activity

A) MDD HX− group (n=21) showed greater reaction time for both negative and positive images than neutral images during the EDP. The MDD Hx+ (n=12) group did not show a reaction time difference between negative and neutral images. The difference in reaction time between neutral and negative images was significantly greater in the MDD Hx− group compared to the MDD Hx+ group (t (34) = 2.78, p < 0.01). B) Amygdala activity during the EDP was greater in the MDD HX+ during both negative positive images than the MDD Hx− group (corr p < 0.001). Error bars: +/− 1 SD.

Figure 3. EDP Brain Activity

Negative images - neutral images: MDD HX+ > -MDD HX− (corr p < 0.001).MDD Hx+ group had greater activity in the left amygdala (MNI: −22, −2, −16) and right hippocampal complex (MNI: 22,−28,−14), and bilateral precuneus (MNI: −12, −46, 6; 10, −50, 8) during negative images than the MDD Hx− group.

Figure 4. Functional Connectivity with Left Amygdala

Greater resting functional connectivity between left amygdala and right hippocampal complex (MNI: 18, −28, −10) and calcarine areas (MNI: 12, −98, 4) in MDD HX+ compared to MDD HX− (corr p < 0.001).