Affect is the behavioral expression of emotion and affect regulation is a set of processes individuals use to manage emotions and their expression to accomplish goals. However, structures involved in affect regulation are among the last to mature in the developing brain; therefore, many adolescents may not be adequately equipped to regulate their affect. Consequently, adolescents are at increased risk of adverse health outcomes associated with poor affect regulation.
Embryologically, the central nervous system develops from bottom to top and from inside to out.1 The limbic system, which engages flight, fight, or freeze behaviors and is located deep within the cerebral hemispheres, is the first part of the brain to develop, whereas the prefrontal cortex, which is the seat of affect regulation, judgment, deductive reasoning, and discernment, does not fully develop until approximately 26 years.1 Therefore, youthful brains are underdeveloped with respect to affect regulation. Metaphorically, emotions and their expression are the “gasoline” that propels the lives of adolescents and adults, and judgment steers the vehicle on course and applies the brakes when necessary to maneuver through life. In other words, youth are neurodevelopmentally predisposed to being “all gasoline, no brakes, and no steering wheel.”