A brief review is presented of hemispheric specialization for different cognitive modes, and of the symptoms that follow disconnection of the two hemispheres by commissurotomy. Our present knowledge of the hemispheres' cognitive specialization and potential for independent functioning provides a framework for thinking about the interaction of cognitive structures, defensive maneuvers, and variations in awareness. Parallels are noted between some aspects of the mental processes of the disconnected right hemisphere and some aspects of primary process thinking and repression.
The hypothesis is proposed that in normal intact people mental events in the right hemisphere can become disconnected functionally from the left hemisphere (by inhibition of neuronal transmission across the cerebral commissures), and can continue a life of their own. This hypothesis suggests a neurophysiological mechanism for at least some instances of repression and an anatomical locus for the unconscious mental contents.
Galin D. Implications for Psychiatry of Left and Right Cerebral SpecializationA Neurophysiological Context for Unconscious Processes. Arch Gen Psychiatry. 1974;31(4):572–583. doi:10.1001/archpsyc.1974.01760160110022