Is economics missing psychology?

Freakonomics has a link to a post from Cato blogger Will Wilkinson on the lack of coherent psychological theory in economics, despite comments from economists that people are acting from fear, thus leading to increased problems in the recent economic crisis .

Will has some interesting points, my favorite being:

For example, if individuals’ decisions about consumption, savings, and debt are rooted in beliefs about their future incomes — a view I think most economists share — then it would seem that an economy-wide decline in personal consumption would indicate that a lot of individuals have more or less simultaneously revised their expectations about their future economic prospects. As far as I can tell no one has a theory of the events that predict revisions in an individual’s estimates of her lifetime income, much less a theory of how the perception of events predicts the magnitude of these revisions.

Economists aren't trained in psychology. In fact, every time I tried to take a class outside my department, such as the few classes I took in sociology, I got a lot of strange looks from some of my professors.

As researchers of human action, economists are in desperate need of a good dose of psychology training. Perhaps the recent financial crisis, and the range of criticisms economists have received from it, might encourage this.