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Have you ever gone without sleep for any long period of time? If so you then you very likely know what sleepless people are talking about when they mumble incoherent phrases like "feeling spacey," "washed out," "dreamy," "eerie," "unreal," and "uneasy." If you go without sleep long enough, odd visual changes begin to occur and sometimes outright visual hallucinations can occur. Finally, there is a generalized sense of uneasiness or a free floating anxiety that seems to pervade the consciousness of the unslept mind. When you put all these elements together you get a picture of someone experiencing mental breakdown.
The common experience of a sleep deprived humanity is that prolonged loss of sleep induces various degrees of mental insanity. Now a special issue of the journal of Consciousness and Cognition (Volume 20, Issue 4, Pages 985-1936 (December 2011) From Dreams to Psychosis: A European Science Foundation Exploratory Workshop Challand Saint Anselme, Italy Edited by Silvio Scarone and Armando D'Agostino) seeks to shed some scientific light on whether sleep and dream dysfunction can lead to insanity or can at least function as a model of psychosis.
There are several excellent papers in the special issue including works on neuroimaging of the dreaming brain/mind, body distortions in dreams, REM behavior disorder, sleep and dreams in frontotemporal dysfunction, hallucinations and dreams, dreams and schizophrenia and the general issue of the relation of dreaming to consciousness. The consensus seems to be that while there are some very compelling analogies between REM sleep/dreaming and some of the psychoses the dis-similarities are just as compelling so that no simple equation between dreams and psychosis can be drawn.
With respect to dis-similarities...one of the very interesting issues taken up by at least one set of authors (Voss and Hobson) is the question as to why animals do not seem to go insane even though they have REM sleep and presumably dream. the answer the authors consider and seem to adopt is that you need Mind or consciousness in order to go insane. You need a self in order to have it break up or break down.
While that answer seems right to me it merely highlights the larger, more mysterious issue of the relation between REMsleep/dreams and the self or consciousness. As I said that issue is discussed very competently by some of the authors in the special issue (e.g., Jennifer M. Windt, Valdas Noreika) but I would like to suggest just two points that seem to speak to the problem we are considering here...why do people experience mental breakdown after prolonged sleeplessness? Why is there a seeming dependence of the SELF construct on the dreaming brain?
The first point is that the empirical data definitely do point to a deep relation between REM sleep and mental stability, i.e. between dreaming and a healthy sense of reality and SELF. The second point is that that relation (between dreaming and SELF) has never received adequate attention in the modern scientific study of dreams.
All of the psychodynamic schools of thought in psychology (the Freudians, Jungians etc) DID investigate the relation between dreaming and identity but modern psychology has dropped the ball or better has not built on the foundational work of these pioneers.
While it is true that most of that work is in the form of case studies and broad theory, it nevertheless is rich in content and worth a second look....not for adequate theories of the dream but for insights into the relation of dreams to SELF.
