Stephen Campbell
Feb 29, 2020
5/10
A fascinating premise and setup, but the execution is tedious
>The Capgras Delusion has been known since the turn of the century but has been treated as a curiosity, an anomaly. The standard explanation, which you find in most psychiatry textbooks, is a Freudian one and the idea is something like this: this young man, like most young people, when he was an infant, growing up, he had strong sexual attraction to his mother, the so-called "Freudian Oedipus complex". But then along comes a blow to the head, and suddenly and inexplicably these sexual urges come flaming to the surface, and he finds himself sexually attracted to his mother. And he says, "My God, if this is my mother how come I'm attracted to her? How come I'm aroused? This must be some other strange woman."
>Now this is an ingenious explanation but it doesn't quite work, because I've seen a patient who has the same delusion about his pet dog. He'll look at his pet dog and say, "Doctor, this is not Fifi. It looks just like Fifi, but in fact it's been replaced by another identical dog". So how does a Freudian explanation account for this, unless you start talking about the inherent bestiality in all human beings or something like that? So what really causes the Capgras Delusion? Well, it turns out that when you look at an object, the message goes to the temporal lobes – to the visual centres in the temporal lobes. But seeing is a multi-level process. After you've recognised it, you also need to respond to the object emotionally. This is obvious when you look at a Picasso or a Rembrandt or any beautiful picture. Even when you look at, say, your mother's face, the appropriate emotional warmth has to be evoked. Or when you look at a lion you have to be afraid. And all of this is part of the visual process, but happening in a different part of the brain.
>Now, what I've suggested is that what's going on in this patient is the message gets to the temporal lobe cortex, so the patient recognises his mother as being his mother and evokes the appropriate memories. But the message doesn't get to the amygdala, because the fibres going from the temporal cortex to the amygdala into the emotional centres are cut, as a result of the accident. Therefore, there is no emotion. There is no warmth. And he says, "If this is really my mother why is it I'm not experiencing any emotions? There's something not quite right here. Maybe she is some other strange woman pretending to be my mother."
- V.S. Ramachandran