Mental Illness & Brain Chemistry

Mental Illness & Brain Chemistry

I mentioned a couple of days ago that I am reading J. Allan Hobson and Jonathan A. Leonard, Out Of Its Mind: Psychiatry in Crisis (Cambridge, Mass.: Perseus Publishing Group, 2001) at the moment. They make an interesting point: that there are strong similarities between dreams and psychosis. This is not only in the sense that both dream state and psychosis involve irrational ideas being accepted by the brain, and seeing things that aren't there, but even at the biochemistry level.

They point out that four neurochemicals play a major part in what happens during dreaming--and in the psychotic brain: serotonin, norepinephrine, acetylcholine, and dopamine. Many of the psychiatric drugs fiddle (with varying degrees of precision) with the levels of these chemicals in the brain. Similarly, alcohol, cocaine, and amphetamines also fiddle with the levels of these chemicals in the brain (pp. 120-3). They make the case that where dreaming is driven by signals from within the brain (perhaps part of the process by which the day's inputs are processed and sorted by the hippocampus pp. 142-3), psychosis is driven by external signals.

Some years back, Drs. Hoffer & Osmond, two Canadian psychiatrists, were arguing for a model of schizophrenia in which the failure of the brain to properly convert norepinephrine played some part in the sensory confusion schizophrenics suffer. One of the doctors took norepinephrine for asthma--and a spoiled batch of it put him in his own hospital with schizophrenic like symptoms for several days, before he recovered. My research for my next book indicates that this theory is now pretty well discounted, but some of the current research is at least in the neighborhood--and fits well with Hobson and Leonard's discussion.