Definition
Automatic Positive Reinforcement occurs when a behavior results in something pleasant or satisfying being added (a reinforcing stimulus), which increases the likelihood that the behavior will happen again in the future. This happens without any external influence or consequence provided by another person.
Example
A child hums to themselves because they enjoy the sound of their own humming. The pleasant sensation or sound reinforces the behavior, making it more likely the child will hum again. The behavior is automatically reinforced because the reinforcement (the enjoyable sound) comes directly from the behavior itself, without anyone else providing a consequence.