This article begins a regular series on how brain research can help us understand young people and ourselves as well. The intent is to alert the reader to important information from recent research on the brain. This initial installment explores the concept of the triune brain, a term coined by neuroscientist Paul MacLean. This refers to three major brain structures which specialize in survival, emotions, and reasoning. These various brain structures and pathways develop and change as the child grows and interacts with the world. Neuroscience confirms that those in closest contact with the child will have the most profound influence on the nature of brain growth and development. Human connections underlie brain connections. The three major brain structures are the: (1) survival brain; (2) emotional brain; (3) logical brain. Working from the bottom up, the most basic brain structure is dedicated to physical survival. This area develops first in the growing fetus. It is sometimes called the reptilian brain because this structure is shared by all living creatures, even those most primitive. This area includes the brain stem, which connects to the spinal cord, and the cerebellum, which handles motor behavior and has a role in emotional calming. The survival brain controls our automonic functions like heartbeat, respiration, reproduction, and the like. Most important to our concern with behavior, the survival brain activates fight and flight reactions and distress cries if danger is detected. The emotional brain is wrapped around the survival brain like a girdle (limbus in Greek) and is called the limbic system. This area is the seat of emotions such as fear, anger, and love. The emotional brain sorts incoming stimuli as pleasurable or threatening. The sentry or danger detector of the emotional brain is the amygdala. It scans for any sign of threat, separating friend from foe. The amygdala sits atop the hippocampus (Greek for seahorse, signifying its shape), which stores emotionally charged events in our memory. The logical brain or neocortex is last to develop. In humans, this makes up the major portion of the brain that distinguishes us from most other animals. In particular, the prefrontal area (behind the forehead) plays a key role in planning, weighing alternatives, making decisions, and regulating emotional impulses. (Contains 1 note.)