In psychology, bicameralism is a hypothesis which argues that the human brain once assumed a state known as a bicameral mind in which cognitive functions are divided between one part of the brain which appears to be "speaking", and a second part which listens and obeys.
The term was coined by psychologist Julian Jaynes, who presented the idea in his 1976 book The Origin of Consciousness in the Breakdown of the Bicameral Mind, wherein he made the case that a bicameral mentality, that is to say a mental state in which there are two distinct sections of consciousness, was the normal and ubiquitous state of the human mind as recently as 3000 years ago. He used governmental bicameralism to metaphorically describe such a state, in which the experiences and memories of the right hemisphere of the brain are transmitted to the left hemisphere via auditory hallucinations. This mental model was replaced by the conscious mode of thought, which Jaynes argues is grounded in the acquisition of metaphorical language.
According to Jaynes, ancient people in the bicameral state would experience the world in a manner that has similarities to that of a modern-day schizophrenic. Rather than making conscious evaluations in novel or unexpected situations, the person would hallucinate a voice or "god" giving admonitory advice or commands, and obey these voices without question; one would not be at all conscious of one's own thought processes per se.
Jaynes inferred that these "voices" came from the right brain counterparts of the left brain language centres—specifically, the counterparts to Wernicke's area and Broca's area. These regions are somewhat dormant in the right brains of most modern humans, but Jaynes noted that some studies show that auditory hallucinations correspond to increased activity in these areas of the brain.
Even though Jaynes' theory seems to be more of a cult today, rather than the object of serious academic debate, this is still a bit interesting in terms of what was discussed during the last session. Also, Dolar's text, in particular, did help to clarify an aspect of both Jaynes' and Lacan's work that I had failed to notice prior to reading it - which obviously is the disctinction, or inner tension, between signifying language and asignifying voice.
If anyone is interested in this, Steven Shaviro has a brief but interesting discussion of Jaynes' theory on his blog. It's been a while since I read the book myself, but I remember it as a bit cheesy from time to time. However, anyone who's interested might benefit from checking it out.