Noncontingent Reinforcement
Noncontingent reinforcement (an example of which is time-based reinforcement) is a style of reinforcement that is not directly tied to any particular behavior and where a research subject might be given a food reward on a regular schedule without the requirement of any specific activity. This schedule of reinforcement can be used to reinforce multiple positive forms of interaction.
An example of this might be to socialize puppies and kittens to human interaction by positively interacting with them every 20 minutes in order to encourage the understanding that contact with humans is positive and desirable. The interaction would occur regardless of the behavior of the animal.