Dreams
A final, rather striking, example of the re-discovered role of emotion is in the field
of sleep and dream research. When REM sleep and its near-perfect correlation with
dreaming were discovered in the 1950s, and the related brain-stem mechanism
discovered in the 1970s (Hobson and McCarley, 1977), Freud’s (1900) dream theory
appeared to lose all scientific credibility. However, more recent research has revealed
that dreaming and REM sleep are doubly dissociable states, controlled by distinct (but
interactive) brain mechanisms (Solms, 1997). Dreaming turns out to be generated by a
network of forebrain structures centered principally around ascending dopamine
systems (see Solms 1997, 2000 for review).
Importantly, dreaming stops completely when fibers in the ventromesial frontal lobes
are severed, after lesion to exactly the same brain region as that targetted in pre-frontal
leucotomy. This is, of course, the same system that mediates powerful positive
emotions (Panksepp, 1998), and is also centrally implicated in hallucinations and
delusions that share many formal features with dreams (Silbersweig et al, 1995). The
landscape of dreaming research, especially as regards emotion, has radically changed,
and it would appear, based on modern findings, that Freud’s classical has much to
recommend it.
This opens the fascinating possibility that emotion may play a generative role in all
classes of false belief states: from dreaming in the neurologically-healthy, to changes
seen after focal brain lesions, and also encompassing the pharmacologically-sensitive
disorders that are central to the several psychiatric states with delusional features. The
empirical foundation for such a grand claim remains limited, but it offers the prospect
of a tempting unification of findings across wide domains.
A final, rather striking, example of the re-discovered role of emotion is in the field
of sleep and dream research. When REM sleep and its near-perfect correlation with
dreaming were discovered in the 1950s, and the related brain-stem mechanism
discovered in the 1970s (Hobson and McCarley, 1977), Freud’s (1900) dream theory
appeared to lose all scientific credibility. However, more recent research has revealed
that dreaming and REM sleep are doubly dissociable states, controlled by distinct (but
interactive) brain mechanisms (Solms, 1997). Dreaming turns out to be generated by a
network of forebrain structures centered principally around ascending dopamine
systems (see Solms 1997, 2000 for review).
Importantly, dreaming stops completely when fibers in the ventromesial frontal lobes
are severed, after lesion to exactly the same brain region as that targetted in pre-frontal
leucotomy. This is, of course, the same system that mediates powerful positive
emotions (Panksepp, 1998), and is also centrally implicated in hallucinations and
delusions that share many formal features with dreams (Silbersweig et al, 1995). The
landscape of dreaming research, especially as regards emotion, has radically changed,
and it would appear, based on modern findings, that Freud’s classical has much to
recommend it.
This opens the fascinating possibility that emotion may play a generative role in all
classes of false belief states: from dreaming in the neurologically-healthy, to changes
seen after focal brain lesions, and also encompassing the pharmacologically-sensitive
disorders that are central to the several psychiatric states with delusional features. The
empirical foundation for such a grand claim remains limited, but it offers the prospect
of a tempting unification of findings across wide domains.
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