Hemisphere deconnection and unity in conscious awareness.

THE following article is a result of studies my colleagues and I have been conducting with some neurosurgical patients of Philip J. Vogel of Los Angeles. These patients were all advanced epileptics in whom an extensive midline section of the cerebral commissures had been carried out in an effort to contain severe epileptic convulsions not controlled by medication. In all these people the surgical sections included division of the corpus callosum in its entirety, plus division also of the smaller anterior and hippocampal commissures, plus in some instances the massa intermedia. So far as I know, this is the most radical disconnection of the cerebral hemispheres attempted thus far in human surgery. The full array of sections was carried out in a single operation. No major collapse of mentality or personality was anticipated as a result of this extreme surgery: earlier clinical observations on surgical section of the corpus callosum in man, as well as the results from dozens of monkeys on which I had carried out this exact same surgery, suggested that the functional deficits might very likely be less damaging than some of the more common forms of cerebral surgery, such as frontal lobotomy, or even some of the unilateral lobotomies performed more routinely for epilepsy. The first patient on whom this surgery was tried had been having seizures for more than 10 years with generalized convulsions that continued to worsen despite treatment that had included a sojourn in Bethesda at the National Institutes of Health. At the time of the surgery, he had been averaging two major attacks per week, each of which left him debilitated for another day or so.