What specific type of stimulus added in positive punishment decreases the frequency of the behavior?

In the context of behavior analysis, a positive punisher is a stimulus that is introduced following a behavior, which then leads to a decrease in the frequency of that behavior in the future. The term "positive" in positive punishment refers to the addition of a stimulus, not to the nature of the stimulus itself being good or bad.

When a positive punisher is applied, it typically serves to provide an aversive consequence that discourages the unwanted behavior. For example, if a child touches a hot stove and feels pain, the pain is a positive punisher. After experiencing this stimuli, the child is less likely to touch the stove again.

This concept is different from negative punishment, where a stimulus is removed to decrease a behavior, and from socially mediated or unconditioned stimuli, which do not directly pertain to the mechanism of adding a stimulus to decrease behavior frequency in the framework of positive punishment.