Depression symptoms and cognitive control of emotion cues: a functional magnetic resonance imaging study

Few studies have examined associations between depressive symptoms and alterations in neural systems that subserve cognitive control. Cognitive control was assessed with an exogenous cueing task using happy, sad, and neutral facial expressions as cues among women with mild to moderate symptoms of depression and a non-depressed control group while functional magnetic resonance imaging (fMRI) measured brain activity. Amygdala and medial/orbital prefrontal cortex (PFC) response to valid emotion cues did not differ as a function of depression symptoms. However, significant depression group differences were observed when task demands required cognitive control. Participants with elevated depression symptoms showed weaker activation in right and left lateral PFC and parietal regions when shifting attentional focus away from invalid emotion cues. No depression group differences were observed for invalid non-emotional cues. Findings suggest that mild to moderate depression symptoms are associated with altered function in brain regions that mediate cognitive control of emotional information.

Prefrontal morphology, 5-HTTLPR polymorphism and biased attention for emotional stimuli

Biased attention for emotional stimuli has been associated with vulnerability to psychopathology. This study examines the neural substrates of biased attention. Twenty-three adult women completed high-resolution structural imaging followed by a standard behavioral measure of biased attention (i.e. spatial cueing task). Participants were also genotyped for the serotonin transporter-linked promoter region (5-HTTLPR) gene. Results indicated that lateral prefrontal cortex (lPFC) morphology was inversely associated with maintained attention for positive and negative stimuli, but only among short 5-HTTLPR allele carriers. No such associations were observed for the medial prefrontal cortex (mPFC) or the amygdala. Results from this study suggest that brain regions involved in cognitive control of emotion are also associated with attentional biases for emotion stimuli among short 5-HTTLPR allele carriers.