Auditory Hallucinations and the Bicameral Mind

Robert Olin, Lancet, 1999, 354, 166.

Sir Jay Goldstein,1 a foresighted thinker in the field of neurosomatic disorders, such as chronic fatigue syndrome, recently made me aware of an important book from 1976 by Julian Jaynes: The origin of consciousness in the breakdown of the bicameral mind.2 According to Jaynes’ daring hypothesis, man had no consciousness until 1000 BC. Before that time, language had developed slowly for a long period: commands from 40,000 BC, nouns from 25,000 BC, and names from 10,000 BC, at the time of the emergence of agriculture. Language, the speech areas, evolved in the left hemisphere (in right-handed) which, as Jaynes underlined, is a mystery since most human structures are bilateral and a neurological organisation necessary for language also exists in the right hemisphere, but with no observable function.

Jaynes proposes that the bicameral mind in man operated between 10,000 BC and 1000 BC. The left hemisphere was the site for speech, the right for hallucinations, which expressed voices and commands of gods and demons. The breakdown of the bicameral mind was according to Jaynes caused by “the weakening of the auditory by the advent of writing, the inherent fragility of hallucinating control, the unworkableness of gods in the chaos of historic upheaval, the positing of internal cause in the observation of differences in others… and a modicum of natural selection.” Then consciousness and self-awareness evolved-and (hopefully) still does.

Jaynes founded his theory on psychohistorical analysis and on such neurobiological knowledge that was available around 1970. As a psychologist, an important part of Jaynes’ theories were based on observations of schizophrenic patients. Neuroimaging techniques of today have illuminated and confirmed the importance of Jaynes’ hypothesis. Belinda Lennox and colleagues (Feb. 20, p. 644)3 used spatial and temporal mapping of neural activity in a right-handed schizophrenic patient to show that his auditory hallucinations occurred in various parts of his right hemisphere, but not in his left which “could explain why the activations are misinterpreted as alien”. Similar findings were reported by Dierks and co-workers.4 Thus Jaynes’ bold hypothesis on schizophrenia has been revived. But, in a broader context, his theories might be important with regard to two questions. Can differences in the evolution and the transition of the unicameral to the bicameral mind to present man with consciousness explain the horrors of our civilisations? What will, as evolution inevitably proceeds, the fourth “camera” contain?


Goldstein, JA. Betrayal By The Brain. Haworth Medical Press, New York; 1996.

Jaynes, J. The Origin of Consciousness in the Breakdown of the Bicameral Mind. Houghton Mifflin Company, Boston; 1976.

Lennox, BR, Bert, S, Park, G, Jones, PB, and Morris, PG. Spatial and temporal mapping of neural activity associated with auditory hallucinations. Lancet. 1999; 353: 644.

Dierks, T, Linden, DE, Jandl, M et al. Activation of Heschl’s gyrus during auditory hallucinations. Neuron. 1999; 22: 615-621.