The brain is the one organ that processes, regulates, and responds to EVERYTHING in our environment.  It becomes the foundation of who we are and who we will become, the basis of our personality, and directs our interaction with the world around us.  Characteristics of our brain are determined by our unique genetics, what we experience, what we learn (consciously and unconsciously), and our health.  

A healthy functioning nervous system monitors our environment, organizes it, prioritizes that information, tells us what is most important or dangerous, thus directing our responses.  Most of us can sit in a sports arena, watching the game and be able to tune out or inhibit the noise, the crowd, the lights, the excitement, and all the stimulation except what we choose to focus on.  Think about how overwhelming it would be if you had to consciously process all that sensory input.  We would not be able to sit comfortably in the arena!

A primary role of the brain function as a regulator is to inhibit our body’s response to sensory input (e.g., sight, sound, touch).  High levels of sensory stimulation are not a negative thing, for most of us, as we are able to regulate / inhibit the stimulation.  If that ability to inhibit is impaired, we are forced to consciously process a barge of sensory information.  The can result in a feeling of over-stimulation / over-arousal.   

Possibly the most prominent behavior problems are a result of an individual’s inability to regulate levels of arousal (e.g., moods, emotions, level of alertness, focus / concentration).  An injury to the brain or emotional/behavioral disorder commonly disrupts that process. 

In observing these children, adolescents, or adults, the following words come to mind to describe their behavior, “irritable”, “over-reacts”, “has a short fuse”, “can’t let go”, “temper tantrum”, “is hot headed”, and the list goes on.  These are typically individuals unable to self-regulate, not because of a “character flaw” or psychopathology, but rather a “neurogenic irritability”, a neurobehavioral characteristic, an inability to self-calm.  Such individuals may become easily over-stimulated, their alarm system goes off, their behavior out of control. The extreme level of over-stimulation may also increase to a point of becoming angry, impulsive, exhibit poor judgment, or inappropriate behavior, potentially aggressive or violent.