The extent to which observed behavior in the complete commissurotomy
patients is supported by only one hemisphere would depend on individual
differences interacting with a variety of factors such as genetics,
intelligence, and so on. The lesson imparted here is that there is
sufficient functional redundancy in the neocortex so that the capacity
to maintain a wide range of abilities is within the control of one
hemisphere. And, yet, as seen in what is missing in the patients'
behavior, one hemisphere is not quite enough. Nature seems to have
intended that the two hemispheres complement each other, that the full
range of human behavior be best accomplished through interaction
between the left and right hemispheres