The Tell-Tale Brain: A Neuroscientist's Quest for What Makes Us Human

Much more bizarre is the Couvade syndrome, in which men in Lamaze classes start developing pseudocyesis, or false signs of pregnancy. (Perhaps mirror-neuron activity results in the release of empathy hormones such as prolactin, which act on the brain and body to generate a phantom pregnancy.)

Even Freudian phenomena such as projection begin to make sense: You wish to deny your unpleasant emotions, but they are too salient to deny completely so you ascribe them to others; it’s the I-you confusion again. As we will see, this is not unlike a patient with somatoparaphrenia “projecting” her paralyzed arm to her mother. Lastly, there is Freudian countertransference, in which the psychoanalyst’s self starts fusing with the patient’s, which can sometimes land the psychoanalist in legal trouble if the patient is of the opposite sex.

Obviously, I am not claiming to have “explained” these syndromes; I am merely pointing out how they might fit into our overall scheme and how they may give us hints about the manner in which the normal brain constructs a sense of self.

AUTISM

In Chapter 5, I presented evidence that a paucity of mirror neurons, or the circuits they project to, may underlie autism. If mirror neurons do indeed play a role in self-representation, then one would predict that an autistic person, even a high-functioning one, could probably not introspect, could never feel self-esteem or self-deprecation—let alone experience self-pity or self-aggrandizement—or even know what these words mean. Nor could the child experience the embarrassment—and the blush—that accompanies the state of being self-conscious. Casual observations of autistic people suggest that all this might be true, but there have been no systematic experiments to determine the limits of their introspective abilities. For example, if I were to ask you what’s the difference between need and desire (you need toothpaste; you desire a woman or man), or between pride and arrogance, hubris and humility, or sadness and sorrow, you would typically think for a bit before being able to spell out the distinction. An autistic child may be incapable of these distinctions while still being capable of other abstract distinctions (such as “What’s the difference between a Democrat and a Republican, other than IQ?”).

Another subtle test might be to see whether a high-functioning autistic child (or adult) can understand a conspiratorial wink, which usually involves a three-way social interaction between you, the person you are winking at, and a third person—real or imaginary—in the vicinity. This requires representing one’s own as well as the other two people’s minds. If I give you a sly wink when telling a lie to someone else (who can’t see the wink), then I have an implied social contract with you: “I am letting you in on this—see how I am tricking that person?” A wink is also used when flirting with someone, unbeknownst to others in the vicinity, although I don’t know if this is universal to all cultures. (And, lastly, you wink to someone to whom you are saying something in jest as if to say, “You realize I am only are joking, right?”) I once asked the famous high-functioning autist and writer Temple Grandin whether she knew what winking meant. She told me that she understands winking intellectually but doesn’t ever do it and has no intuitive feel for it.

More directly relevant to the framework of the present chapter is the observation made by Leo Kanner (who first described autism) that autistic children often confuse the pronouns “me” and “you” in conversation. This shows a poor differentiation of ego boundaries and a failure of the self-other distinction which, as we have seen, depends partially on mirror neurons and associated frontal inhibitory circuitry.

THE FRONTAL LOBES AND THE INSULA

Earlier in this chapter, I suggested that apotemnophilia results from a mismatch between somatosensory cortices S1 and S2, on the one hand, and on the other the superior (and inferior) parietal lobules, the region where you normally construct a dynamic image of your body in space. But where exactly is the mismatch detected? Probably in the insula, which is buried in the temporal lobes. The posterior (back) half of this structure combines multiple sensory inputs—including pain—from internal organs, muscles, joints, and vestibular (sense of balance) organs in the ear to generate an unconscious sense of embodiment. Discrepancies between different inputs here produce vaguely articulated discomfort, as when your vestibular and visual senses are put in conflict on a ship and you feel queasy.