Converging evidence has linked the anterior mid-cingulate cortex to negative affect, pain and cognitive control. Shackman and colleagues proposed this region uses information about punishment to control aversively motivated actions. Studies on the effects of lesions allow causal inferences about brain function; however, naturally occurring lesions in the anterior mid-cingulate cortex are rare. In two studies we therefore recruited 94 volunteers, comprising 15 patients with treatment-resistant depression who had received bilateral Anterior Cingulotomy, which consists of lesions made within the anterior mid-cingulate cortex, 20 patients with treatment-resistant depression who had not received surgery and 59 healthy controls. Using the Ekman 60 Faces paradigm and two Stroop paradigms, we tested the hypothesis that patients who received Anterior Cingulotomy were impaired in recognising negative facial affect expressions but not positive or neutral facial expressions, and impaired in Stroop cognitive control, with larger lesions being associated with more impairment. Consistent with hypotheses, we found that larger volume lesions predicted more impairment in recognising fear, disgust and anger, and no impairment in recognising facial expressions of surprise or happiness. However we found no impairment in recognising expressions of sadness. Also consistent with hypotheses, we found that larger volume lesions predicted impaired Stroop cognitive control. Notably, this relationship was only present when anterior mid-cingulate cortex lesion volume was defined as the overlap between cingulotomy lesion volume and Shackman and colleague’s meta-analysis derived binary masks for negative affect and cognitive control. Given substantial evidence from healthy subjects that the anterior mid-cingulate cortex is part of a network associated with the experience of negative affect and pain, engaging cognitive control processes for optimising behaviour in the presence of such stimuli, our findings support the assertion that this region has a causal role in these processes. Whilst the clinical justification for cingulotomy is empirical and not theoretical, it is plausible that lesions within a brain region associated with the subjective experience of negative affect and pain may be therapeutic for patients with otherwise intractable mood, anxiety and pain syndromes.
- mid-cingulate cortex
- treatment-resistant depression
- cognitive control