Dreaming: Two book reviews

Dreaming: Two Book Reviews

Dreaming and 13 Dreams are the two most recent of several books by Professor Hobson that summarize his many years of research on dreams and the sleeping brain. Hobson is an excellent writer, and so these books are a pleasure to read. In them he delivers much of the current knowledge on the dreaming brain in an easy and informal voice that carries the reader along effortlessly from chapter to chapter. Both are small books, and both cover much the same ground. Dreaming presents its material in a systematic chapter by chapter, topic by topic, fashion, covering many of the basics of the psychology and physiology of sleep itself, as well as dreaming in particular. 13 Dreams, on the other hand, narrates thirteen dreams from Hobson’s personal journals, using each as a starting point for a free-ranging essay on sleep and dreaming. I would not detract from the pleasure of reading these by describing them here, but I will point out the fascinating Prologue in which Hobson publishes for the fist time an autobiographical account, penned posthumously by Freud himself, of the latter’s efforts as a young man to create a “Project for a Scientific Psychology” founded entirely on an understanding of the physiology of the brain. In this little jewel of an essay, Freud admits to the Project’s failure, sadly because cause the requisite knowledge of the brain was not forthcoming until he was too old to take advantage if it.

I now turn my attention to Dreams. In it we learn in a few short chapters, without the usual encrustations of academic scholarship (the serious investigator will have to look elsewhere for rich citations), much of the history of research on sleep, dreaming, and the brain. Hobson and McCarley’s well-known Dreaming, like all conscious experience, is the direct product of neuronal activity of the brain activation-synthesis hypothesis, first published in 1977, plays a major role in this history. The original form of this hypothesis argued that dreams are the result of powerful pulses of adrenergic stimulation to the optic cortex, arising from the brain stem in the form of high voltage pontine-geniculate-occipital (PGO) spikes that also stimulate rapid eye movement (REM). The noisy character of these “PGO waves” during dreaming was said to produce unpatterned activity in the optic cortex which, in Hobson and McCarley’s words, “may be making the best of a bad job” by producing the dream imagery we experience. The implications of this theory for any content based interpretative view of dreaming are stark and obvious: don’t waste your time!

Since the introduction of the original activation-synthesis hypothesis Hobson’s work at the Harvard Medical School has led to a variety of modifications to the original notion. His present thinking is based more on studies of neurochemistry and the ever-advancing findings of brain imaging studies. A current assessment of the dreaming brain emphasizes the importance of heightened emotions, stimulated by cholinergic hyperstimulation of limbic structures; coupled with a deregulation of attention, working memory, and reasoning, resulting from aminergic demodulation of pre-frontal areas of the brain (especially the dorsolateral prefrontal cortex). During dreaming a widely distributed shift form adrenergic to cholinergic Hobson has proven the value of form analysis beyond any shadow of a doubt dominance results in the disinhibition of cortical networks resulting in a hyperassociative flow of images combined with the release of long-term memory representations. Sensory input is blocked by presynaptic inhibition and motor output by postsynaptic inhibition, while at the same time top-down cortical and frontal control is lost to disinhibited subcortical network activation that releases heightened subcortical emotional and instinctual activation. The dream experience is irrational, hyperassociative, and emotional. Its content is ladened with long-term memories, but there is little working memory during the dream itself, and little or no self-reflection. Hobson believes it is most like a state of delirium.

Interestingly, Hobson now admits to the reality of dream experiences outside of REM sleep, but based on reports form the dream laboratory argues that they are less intense than REM dreams, often approximating a kind of vague, directionless, rumination over the events of the day.

Both of these books seem to have the same two main agendas. The first is to present a readable summary of the state of the art in research on REM sleep dreaming and the brain, and the second is to convince the reader that content and especially interpretative approaches to the study of dreams are pre-scientific and pointless. Freud is his whipping boy for this because, he argues, Freud would have much preferred a brain based approach to dreaming if he could have had it. Instead he chose the path of symbolic content analysis, making many foolish errors along the way. To put Hobson’s view in a nutshell, dreaming, like all conscious experience, is the direct product of neuronal activity of the brain. Insofar as we understand the chemistry and physiology of that activity, we understand dreaming. The boundary conditions for Hobson’s argument are that (1) the brain acts for its own reasons, some of which enter into consciousness and some of which does not, and (2) once these physiological reasons are understood scientifically there is nothing more to add. The brain’s business is its own. Our understanding of dreams is only diminished by wrong-minded attempts to plumb them for symbolic content, or worse yet to read them in terms of any kind of anomalous influence.

Over and over through both books Hobson emphasizes the importance of the analysis of form over that of content. The former examines general features such as the intensity of visual imagery, strength and quality of emotion, presence of irrational thought, absence of working memory, “bizarreness” of dream sequences, delusional beliefs, and so on.

Hobson has proven the value of form analysis beyond any shadow of a doubt, but to me at least it is less clear why he is so stridently opposed any kind of content or symbolic analysis. Judging from these pages, he seems to have given far too little attention to such approaches to warrant an authoritatively dismiss. In one of the few systematic justifications he makes for this position he admits, near the end of Dreaming, that he once firmly believed he could see meaning in a sequence of dream subplots, even across scene changes. But he then rejects the notion based on a study in which “highly trained, practicing psychoanalysts” failed to match-up randomized dream fragment reports to their original sequences. But this finding hardly proves that the dreams contain no symbolic material, or even that there was no coherency to the original sequences. I am reminded of a nearly forgotten investigation from the 1950s in which a team of psychiatrists interviewed a large number of lobotomized and non-lobotomized patients at the Lexington Veterans Administration psychiatric Hospital. They failed to distinguish those in one group from those in the other. The moral here is that one usually has to know what one is looking for in order to find it.

© 2005 Allan Combs

Book Information

Dreaming: An Introduction to the Science of Sleep
By J. Allan Hobson
Oxford University Press; 2002. 170 pages, index.;
Cloth 19.80 USD, ISBN 0-192803-04-2;
Paper 15.95 USD, ISBN 0-192804-82-0.

13 Dreams Freud Never Had: The New Mind Science
By J. Allan Hobson
Pi Press; 2005. 204 pages, index.;
Cloth 24.95 USD, ISBN 0-131472-25-9.