Theories and Models in Cognitive Psychology
Donald A. Norman
University of California, San Diego
As I learn more, I know less. If I had been invited to write this chapter 10 or even 5 years ago, I would have had a lot to write. Then I knew the answers. I could have told you what the cognitive mechanism was. The problem is that the more the field progresses, the less I know. Today I will simply give a short commentary of my view of evoked potentials, which is bound to be controversial, along with a commentary on my view of cognitive mechanisms, which is also bound to be controversial.
The main point to those who study evoked potentials is: "Welcome to Cognitive Psychology." I'm impressed by how much all of you are like all of us. I have been following the evoked potential literature for a number of years for several different reasons. For one, I find it interesting. It is obvious that there is a relationship between what goes on in the brain and what goes on in the mind. ERPs give direct measurements of ongoing events that we cannot get by behavioral measurements. By combining electrical recording with the behavioral measurement and with observations of introspections and beliefs, we obtain a more complete picture. In fact I don't think that we ought to be in two fields. We are all interested in related issues: We should be one field.
The thing that bothers me, though, is that those who study ERPs have awfully simple notions about the mechanisms of the brain. This is very surprising to me. I thought that anybody who knew anything about neurological circuits would be more sophisticated, not more simple. Look at the brain. It is quite clear that there is not a simple, sequential, linear stage of operation. You have all those millions and billions of neurons, billions of neuronal connections, and