What is the primary basis for interval schedules of reinforcement?

The primary basis for interval schedules of reinforcement is indeed the time elapsed before reinforcement. In interval schedules, the reinforcement is delivered after a certain amount of time has passed, regardless of how many responses occur during that time. This means that the behavior is rewarded based on the passage of time rather than the frequency of responses.

For instance, in a fixed interval schedule, the first response after a specific duration of time is reinforced. This leads to a pattern of behavior where individuals may increase their response rate as the time for reinforcement approaches, inherently tying the behavior to the timing rather than the number of actions taken within that period.

Other options, while related to reinforcement in general, do not specifically address the mechanics of interval schedules. The number of responses pertains more to ratio schedules, the consequences of behavior are a broader concept that encompasses all forms of reinforcement rather than being specific to either interval or ratio schedules, and the types of behaviors might be relevant for understanding what can be reinforced, but they don't define the basis of the interval schedule itself.