If the onset of a light reliably signals the onset of food, a rat in a Skinner box will work to turn on the light. In this case, the light is a reinforcer.

If the onset of a light reliably signals the onset of food, a rat in a Skinner box will work to turn on the light. In this case, the light is a unconditional reinforcer.

Explanation:

In behavioral psychology, conditioning is implemented as an outcome that will enhance the future behavior of an individual whenever a particular antecedent stimulus precedes that behaviour, also relate with enhancement of memory.

There are two forms of reinforcement, defined as positive reinforcement and negative reinforcement; positive is where a bonus on the presentation of the desired behavior is given, and negative eliminates an unwanted factor in the setting of the individuals whenever the required behavior is accomplished.