The dream between neuroscience and psychoanalysis

Abstract

Neuroscientific interest in dream started in 1953 with the discovery of REM sleep by Aserinsky and Kleitman. Subsequently, psychophysiological findings took the dream into the realm of biology. The dichotomous model of REM and non-REM sleep is described as a basis for thought-like activity (non-REM sleep) and dreaming (REM sleep). However, psychophysiological research has shown that people dream in all phases of sleep although with different characteristics. Bioimaging studies indicate that during REM sleep there is activation of the pons, the amygdala bilaterally and the anterior cingulate cortex, and de-activation of the posterior cingulate cortex and the prefrontal cortex. The images suggest there is a neuroanatomical frame within which dreams can be generated. Various evidence indicates that REM sleep and dream are dissociated events. The latter is induced by complex dopaminergic circuits involving forebrain mechanisms that do not govern REM sleep. These structures are: the anterior and lateral hypothalamic areas, the amygdaloid complex, the sub-ventral striatal areas, the temporo-occipital areas, the anterior cingulate cortex and the insula. Dreams are abolished by an interruption of these dopaminergic circuits. Psychoanalysis studies the dream from a completely different angle. Freud believed it was the expression of hallucinatory satisfaction of repressed desires. Today it is interpreted as the expression of a representation of the transference in the hic et nunc of the session. At the same time it also has symbol-generating functions which provide an outlet by which affective preverbal and presymbolic experiences as well as fantasies and defences stored in the implicit memory and part of an early unrepressed unconscious can be represented and made verbalisable and thinkable. From the psychoanalytical point of view, the dream transcends neurobiological knowledge and looks like a process of internal activation that is only apparently chaotic, but is actually rich in meanings, arising from the person's affective and emotional history.