Prediction Error

Prediction error is a mismatch between what the brain expects to happen and what actually occurs. When reality differs from expectations, the brain generates a signal indicating that its current understanding or internal model may need updating. These signals help drive learning, attention, and adaptation by prompting the brain to revise assumptions based on new information. Larger prediction errors reflect greater discrepancies between expectations and reality and may lead to stronger learning updates. Prediction errors can occur across many experiences, including sensory events, emotional experiences, social interactions, and expectations about safety or relationships. For example, hearing a sudden loud bang may create a large prediction error, prompting alertness while the brain attempts to determine the source. Also see Prediction, Revision, and Reward Prediction Error.