ABSTRACT
Natural language and consciousness, however, are evolutionarily recent facets of brain function, and they coexist with other systems which are more a part of our biological heritage as vertebrates. These relatively primitive systems, which are also capable of registering experiences and regulating purposeful behaviors, operate largely outside of conscious awareness. Brain damage can lead to a variety of types of disturbance in mental function. In the early 1970s, the effort to manage intractable epilepsy by split-brain surgery was revitalized by Donald Wilson of the Dartmouth Medical School. A series of tests were designed to assess various features of self-consciousness. These observations, it would seem, argue quite convincingly that the self can be split and doubled following brain bisection. These observations of course are only relevant to the extent that it can be shown that in our daily lives the conscious self is confronted with behaviors produced by non-conscious systems.
