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.

Prehistory. As reptiles adapted entirely to life on land, terrestrial legs grew longer and stronger than those of aquatic-buoyed amphibian ancestors. In the reptilian spinal cord and brain stem, antigravity reflexes worked to straighten limbs through extensor muscle contractions which lifted the body higher off the ground. Advances in the forebrain's basal ganglia enabled reptiles to walk more confidently than amphibians--and to raise and lower their bodies and broadsides in status displays. The reptile's high-stand display, e.g., presages our own pronated palm-down cues of emphasis while speaking.

Neuro-notes I. 1. The protoreptilian brain, as defined by MacLean, consists of systems a. in the upper spinal cord, b. in the midbrain, and c. in the forebrain's diencephalon and basal ganglia (Isaacson 1974). 2. "The major counterpart of the reptilian forebrain in mammals includes the corpus striatum (caudate plus putamen), globus pallidus, and peripallidal structures [including the substantia innominata, basal nucleus of Meynert, nucleus of the ansa peduncularis, and entopeduncular nucleus]" (MacLean 1975:75).

Neuro-notes II. 1. As a footnote, the relatively high nonverbal IQ of the reptilian basal ganglia was recruited for the development of intelligence in birds, specifically, in the hyperstriatum and neostriatum (rather than, as with mammals, in the cerebral cortex). 2. "Within the avian telencephalon, the dorsal ventricular ridge (DVR) contains higher order and multimodal integration areas. Using multiple regressions on 17 avian taxa, we show that an operational estimate of behavioral flexibility, the frequency of feeding innovation reports in ornithology journals, is most closely predicted by relative size of one of these DVR areas, the hyperstriatum ventrale (Timmermansa et al. 2000:196).


1. An involuntary motor system of the reptilian brain used to initiate body movements, facial expressions, and postures. 2. Large, rounded masses of forebrain, used subconsciously to adjust, coordinate, and smooth out body movements, e.g., for speaking, smiling, walking, and pointing.

Usage: For neuroanatomist Paul D. MacLean, the basal ganglia are important parts of our reptilian heritage. Territorial gestures and postural displays, e.g., of dominance and submission, are shaped by these subcortical structures. Such status signs are analogous, MacLean thinks, to nonverbal displays of modern reptiles used to show physical presence, to challenge competitors, and to attract mates (MacLean 1990).


1. The [basal ganglia's] putamen is mainly connected to the premotor and motor cortex and overactivity [i.e., oversupply of dopamine] in this pathway is thought to account for the physical tics in Tourette's syndrome" (Carter 1998:67).

2. The [basal ganglia's] caudate nucleus has more connections to the orbital cortex--an area concerned with higher order planning of activity.

Overactivity in this pathway [i.e., dopamine excess] is thought to result in obsessive-compulsive disorder [OCD]" (Carter 1998:67).

3. Studies ". . . suggest the existence of certain pathophysiologically important abnormalities in central neurocircuitries, especially in cortico-striatal [i.e., basal ganglia]-thalamic circuitry, in OCD" (Arai 2000).

Anatomy. Our basal ganglia represent a more ancient motor system than what was to develop millions of years later in the brain's neocortex. Less skilled, e.g., than the neocortex's primary motor area, the basal ganglia control basic movements such as the human arm-swing. While walking, we automatically swing our arms because the basal ganglia assume we are still quadrupeds.

Evolution. In early reptiles, the basal ganglia's archistriatum (i.e., the "most ancient" striatum, or amygdala) and paleostriatum (i.e., the [merely] "ancient" striatum, or globus pallidus) evolved to show identity, power, and submission through programmed movements and postural displays (see ANTIGRAVITY SIGN, CROUCH). In early fishes, the precursor circuits of our present basal ganglia were linked to the primeval "smell brain," and led to swimming motions toward positive chemical signals (e.g., food and mates) and away from negative chemical signs (e.g., of enemies; see AROMA CUE).

Neuro-notes I.

Apart from our conscious awareness, the basal ganglia set patterns for key body postures and expressive cues. They turn-on and switch-off ancient spinal circuits for locomotion and postural communication, e.g., and hindbrain circuits for facial expressions and emotional displays (see PALEOCIRCUIT). Basal-ganglia damage from Parkinson's disease shows in a rigid, expressionless, masklike face and a stiff, shuffling gait with non-swinging motionless arms.

Neuro-notes II.

1. ". . . the apparent site of that extra brain power [required for the ability to speak a second language, whether mastered as a child or as an adult] is a deep brain region called the putamen [of the basal ganglia] . . ." (Barinaga 1995:1437).

2. ". . . 'there is some sort of extra control of articulation' required for them to speak their second language" (Barinaga 1995:1437).

Neuro-notes III.

1. "Firstly, the BG provide internal motor cues that enable the release of submovements from the SMA [supplementary motor area; see STEEPLE, Neuro-notes II], for execution by the motor cortex. The cue (phasic neuronal activity) interacts with the SMA (sustained neuronal activity) to string submovements together in the correct timing sequence. The second function is to contribute to cortical motor set (sustained neuronal activity) which maintains whole movement sequences in readiness for running and execution. This contribution may be to the SMA, premotor area or to both" (Iansek et al. 1995).

2. "The BG is only utilized in these two functions when the movements or sequences are skilled and require few attentional resources for their performance" (Iansek et al. 1995; see NONVERBAL LEARNING).

3. "In Parkinson's disease a defective cue leads to slowing of skilled movement sequences and associated instability of submovements (each submovement cumulatively decreases in amplitude and velocity). This is the phenomenon of hypokinesia. A defect in the contribution to motor set leads to an inability to initiate whole skilled movement sequences (akinesia)" (Iansek et al. 1995; italics added).


To HiddenMysteries Internet Book Store

Search Query
Search this Reptilian Agenda Website

HiddenMysteries and/or the donor of this material may or may not agree with all the data or conclusions of this data.
It is presented here 'as is' for your benefit and research. Material for these pages are sent from around the world. Reptilian Agenda Website is a publication of TGS Services
Please direct all correspondence to
TGS HiddenMysteries, c/o TGS Services,
22241 Pinedale Lane, Frankston, Texas, 75763

All Content © HiddenMysteries - TGS (1998-2005) Internet Store ~ HiddenMysteries Information Central
Texas National Press ~ TGS Publishers Dealers Site

All Rights Reserved

Please send bug reports to

FAIR USE NOTICE. This site may at times contain copyrighted material the use of which has not always been specifically authorized by the copyright owner. We are making such material available in our efforts to advance understanding of environmental, political, human rights, economic, democracy, scientific, and social justice issues, etc.. We believe this constitutes a 'fair use' of any such copyrighted material as provided for in section 107 of the US Copyright Law. If you wish to use copyrighted material from this site for purposes of your own that go beyond 'fair use', you must obtain permission from the copyright owner.

In accordance with Title 17 U.S.C. Section 107, the material on this site is distributed without profit to those who have expressed a prior interest in receiving the included information for research and educational purposes. For more information go to:

United States Code: Title 17, Section 107 Notwithstanding the provisions of sections 106 and 106A, the fair use of a copyrighted work, including such use by reproduction in copies or phonorecords or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use the factors to be considered shall include - (1) the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes; (2) the nature of the copyrighted work; (3) the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and (4) the effect of the use upon the potential market for or value of the copyrighted work. The fact that a work is unpublished shall not itself bar a finding of fair use if such finding is made upon consideration of all the above factors.