Cognitive introspective psychology and related cognitive science can no longer be ignored experimentally, or written off as "a science of epiphenomen… - Roger Sperry

There probably is no more important quest in all science than the attempt to understand those very particular events in evolution by which brains worked out that special trick that has enabled them to add to the cosmic scheme of things: color, sound, pain, pleasure, and all the other facets of mental experience.

I have a very one-track mind that needs to concentrate. I asked myself which issue is more important: whether mental states are more left- or right-hemispheric, or whether they are causal in brain function. From weighing the pros and cons, I decided that the left-brain, right-brain work was well in orbit and that it would be more important to shift my primary focus to consciousness. The mind-brain issues are intrinsically more compelling. They carry strong humanistic as well as scientific implications. I could foresee changes in our world view, guiding beliefs, and social values. In the context of today's worsening world conditions and our imperiled future, this work seemed far more important than whether you can find a brain theory enabling people to learn faster, draw better, make better medical diagnoses, and so on. We're beginning to learn the hard way that today's global ills are not cured by more and more science and technology.

With few exceptions, the bulk of the collected lesion evidence up through the 1950s into the early '60s converged to support the picture of a leading, more highly evolved and intellectual left hemisphere and a relatively retarded right hemisphere that by contrast, in the typical righthander brain, is not only mute and agraphic but also dyslexic, word-deaf and apraxic, and lacking generally in higher cognitive function.