The self and depression: Four psychological theories and their potential neural correlates

We review theory and research pertaining to psychodynamic, social, humanistic, and ethological models of the self and depression and examine research into the neurobiological bases of the self and depression. We provide a narrative review of classic and recent empirical evidence pertaining to these four models of the relation of the self to depression as well as exemplar relevant neurobiological research. Evidence stemming from each of the four theories reviewed here shows a robust relationship between deficits in the sense of self and depressive symptoms, as well as increases in depressive symptoms over time. A smaller body of literature has linked one's sense of self to onsets of depressive episodes. A growing body of literature has linked self-relevant variables to functioning in various prefrontal and cortical midline brain regions as well as emotion and reward processing brain regions which have in turn been linked to depression. Evidence has therefore converged across all four theories and confirmed that a deficit in one's sense of self confers risk for depression and that there is substantial overlap in the brain areas associated with one's sense of self and depression.