First-person reports of Major Depressive Disorder reveal that when an individual becomes depressed a profound change or ‘shift’ to one’s conscious experience occurs. The depressed person reports that something fundamental to their experience has been disturbed or shifted; a change associated with the common but elusive claim that when depressed one finds oneself in a ‘different world’ detached from reality and other people. Existing attempts to utilise these phenomenological observations in a psychiatric context are challenged by the fact that this (...) experiential ‘shift’ characteristic of depression appears mysterious and resists analysis in scientific terms. This paper offers a way out of this predicament. The hypothesis proposed is that when an individual becomes depressed, the individual departs from a state of ordinary wakeful consciousness and enters a distinctive global state of consciousness akin to dreaming and the psychedelic state. After unpacking and motivating this hypothesis in the context of research in consciousness science, I outline two of its important implications for the neurobiology of depression and psychedelic psychiatry. The upshot is a promising and conceptually well-motivated hypothesis about depression which is apt for empirical uptake and development. (shrink)

Randolph Nesse argues that evolutionary theory is the key element in elaborating a valid criterion demarcating the normal from the pathological in psychiatry. By focusing on the application of Nesse’s criterion on the demarcation of normal low mood from pathological depression, I argue – contrary to Nesse’s claims – that evolutionary theory cannot generate a valid criterion from the differentiation of normal low mood states from pathological depression. Indeed, expression in conformity to evolved functions cannot constitute a sufficient condition for (...) normality, as Nesse’s project should imply. Moreover, grounding normality in evolved functions presupposes a kind of fixity of our emotional states, which seems unwarranted in the light of a constantly changing environment. As a result of these limitations, I suggest that the relevant distinction in psychiatry should not be “normality” versus “abnormality”, but, rather, “that which requires intervention” versus “that which does not”. (shrink)