How odd that Charlie would not know that it is his arm up Mrs. Randthorpe-Fitzgerald's dress. But we all remember that Charlie suffered an infarction of his right insular cortex following a stroke last spring. Yes, of course, Charlie must be suffering from left sided neglect -- he doesn't know that his left arm is actually his.
But wait a minute! It is Charlie's right arm that is up Mrs. R-F's dress. Charlie, you dog! And why is Mrs. R-F smiling?
island into itself, and is in many ways like a separate brain. But the insula happens to be crucial to a person's sense of self, and to his consciousness. Here is how:
It is remarkable to think that such a small, hidden patch of cortex could be so pivotal to the "soul" of each human being. Al Fin has long championed the concept of "Embodied Cognition", the idea that a mind must have a body in order to be functionally conscious. Particularly when one's consciousness rests so crucially upon a sense of self.
The insula is also thought to be important in the act of decision-making including, perhaps, the making of moral decisions. That makes sense, given the importance of the insula to one's internal body sense, or "gut sense."
Many of our decisions are based upon gut instincts, as it were. Some acts and people "make us sick", while others leave us weak, strong, or make our heads hurt. The way our bodies feel about things can influence us far more than we realise.
And so we leave the insulae of one armed Charlie and Mrs. R-F in the parlour, performing an ancient "dance of the insular cortices."
Meanwhile we may contemplate how it would be possible to insert an insula-like processor into a machine brain, to give it a sense of embodiment. It would be but a bare beginning, of course. But it would be a rational beginning.