A Word on the Reptilian Brain

. . . 'She was full of reptiles.' --Joseph Conrad (Lord Jim)

Evolution. 1. Collectively, those early parts of the human brain which developed during the reptilian adaptation to life on land. 2. Of particular interest are modules of the forebrain which evolved to enable reptilian body movements, mating rituals, and signature displays.

Usage I: Many common gestures, postures, and nonverbal routines (expressive, e.g., of dominance, submission, and territoriality) elaborated ca. 280 m.y.a. in modules of the reptilian brain. The latter itself evolved from modules and paleocircuits of the amphibian brain.

Usage II: In the house of the reptile, it makes a difference whether one crouches or stands tall. Flexing the limbs to look small and submissive, or extending them to push-up and seem dominant, is a reptilian ploy used by human beings today. Size displays as encoded, e.g., in boots, business suits, and hands-on-hips postures, have deep, neural roots in the reptilian forebrain, specifically, in rounded masses of grey matter called basal ganglia.

Literature: "Of these the vigilance I dread, and to elude, thus wrapt in mist of midnight vapor, glide obscure, and pry in every bush and brake, where hap may find the serpent sleeping, in whose mazy folds to hide me, and the dark intent I bring." --John Milton (Paradise Lost, Book IX; 1667)

Reptilian ritual. In Nonverbal World, the meaning of persistence (e.g., repeated attempts to dominate) and repetition (e.g., of aggressive head-nods or shakes of a fist) are found in underlying, reptilian-inspired rituals controlled by the habit-prone basal ganglia (a motor control area identified as the protoreptilian brain or R-complex by Paul D. MacLean [1990]).

Reptilian routine. According to MacLean (1990), our nonverbal ruts start in the R-complex, which accounts for many unquestioned, ritualistic, and recurring patterns in our daily master routine. Like a fence lizard's day--which starts with a cautious commute from its rock shelter, and ends with a bask in the sun--our workday unfolds in a series of repetitive, nonverbal acts. Countless office rituals (from morning's coffee huddle, e.g., to the sacred lunch break) are performed in a set manner throughout the working days of our lives.