Dr. Hoo, if I may- the split-brain studies and related studies show that there are tremendous variances in how individual brains work, how they respond to accidents, etc. So you're right.

What I want to mention is that an important corollary to your point is that an individual brain can tell us a great deal precisely because it is widely variant. Sometimes we just simply don't realize that a certain type of phenomenon or response is possible; we are early enough in the study of the brain to be able to use clues like individual results very aggressively to determine possibilities, and to gain insights from variance itself.

Interestingly, the woman with the damaged left brain at TED had a fairly common reaction, but a more common reaction to her expressed ecstasy, etc. is depression and higher levels of fear and stress. Suicide risk is far more common with broad left-side damage than right. One theory frames the reason in terms of the right hemisphere needing the left to provide a decision-making capability: that issues (sometimes termed exceptions) are brought up by the sensitive right hemisphere, and it relies on the process-centric modules on the left to resolve how to handle the exceptions. Without that input, things may get in suspended animation, if you will, and the lack of resolve on even simple issues causes stress, etc. In the speaker's case, the gestalt capability of the right side seemed to trump any such consideration. That's probably because of where her damage was: when we talk about brain damage, hemispheric talk can get useless pretty fast.

So your point is especially pertinent with this case. There is an important offset to the speaker's implied assertions about the right side that turns her story on its head a little, and makes the whole business healthily complex. I wish she would've done us the courtesy of that insight as well, so the hemispheric myth was aligned better with reality.

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