Advances in the study of cognitive impairments in severe depressive disorders

Severe depressive disorders exhibit significant heterogeneity in cognitive impairment. This can be categorized into three main subtypes: cognitive retention type, selective impairment type, and comprehensive impairment type. However, the consistency of these findings across studies is affected by differences in sample characteristics, assessment tools, and statistical methods. Current evidence from neurobiological mechanisms primarily focuses on the comprehensive impairment type. Preliminary research indicates that this subtype is characterized by dysfunction in the cognitive control circuits involving the dorsolateral prefrontal lobe and dorsal anterior cingulate cortex. There may also be changes in specific structures, neuroelectrophysiological abnormalities, and metabolic alterations associated with this subtype. Exploratory interventions targeting these cognitive control circuits have shown promising results. Repeated transcranial magnetic stimulation, sensory cueing training, and alpha...