Individuals with the post-traumatic stress disorder process emotions in subcortical regions irrespective of cognitive engagement: a meta-analysis of cognitive and emotional interface

Post-traumatic stress disorder (PTSD) manifests as emotional suffering and problem-solving impairments under extreme stress. This meta-analysis aimed to pool the findings from all the studies examining emotion and cognition in individuals with PTSD to develop a robust mechanistic understanding of the related brain dysfunction. We identified primary studies through a comprehensive literature search of the MEDLINE and PsychINFO databases. The GingerALE software (version 2.3.6) from the BrainMap Project was used to conduct activation likelihood estimation meta-analyses of the eligible studies for cognition, emotion and interface of both. Relative to the non-clinical (NC) group, the PTSD group showed greater activation during emotional tasks in the amygdala and parahippocampal gyrus. In contrast, the NC group showed significantly greater activation in the bilateral anterior cingulate cortex (ACC) than did the PTSD group in the emotional tasks. When both emotional and cognitive processing were evaluated, the PTSD group showed significantly greater activation in the striatum than did the NC group. No differences in activation between the PTSD and NC groups were noted when only the cognitive systems were examined. Individuals with PTSD exhibited overactivity in the subcortical regions, i.e., amygdala and striatum, when processing emotions. Underactivity in the emotional and cognitive processing intermediary cortex, i.e., the ACC, was especially prominent in individuals with PTSD relative to the NC population following exposure to emotional stimuli. These findings may explain the trauma-related fear, irritability, and negative effects as well as the concentration difficulties during cognitive distress associated with emotional arousal, that are commonly observed in individuals with PTSD.