Slide 2-2

A time unit has a start and an end. A temporal task could be as simple as calling a friend when they get home from work. The detail is not to call too soon or wait longer than necessary. In psychology, this is called a fixed-interval schedule. The first response after the scheduled time elapses is reinforced.

The way this functional relationship is studied is to repetitively present a task which provides a reinforcer (food) for the first response after a fixed period of time.

Slide 2-3

The worst case solutions are: continuous responding, or waiting longer than the requirement. The ideal is to respond once at exactly the instant that the reinforcer first becomes available.

The behavior actually obtained is many responses throughout the latter portion of the interval.

We could say, of course, "oh, the bird just doesn't know what time it is." Unfortunately, that answer misses the whole point. If that is offered as an answer, then the question simply becomes why doesn't the bird know what time it is?

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Date Last Reviewed : May 26, 2003