Threesology Research Journal
The Triune Brain

(The Study of Threes)

Simply stated, Paul MacLean's triune brain hypothesis distinguishes that the human brain is 3 brains in 1:

triune brain concept

To enhance our appreciation of brain development with respect to categorizing attributes that may help us to better distinguish between a criminal and non-criminal brain, we need to elaborate on a means to help us in differentiating characteristic related to these 3 different brain sections:

Attributes of the brain hemispheres show a distinctive (but somewhat overlapping) partitioning along a 1-patterned, 2-patterned, 3-patterned formula, with the earlier brain structures exhibiting a smaller numerically identifiable value, just as we find in the development of Primordial Germ Layers to the extent that we humans, as a complex organism, grow from 3 Germ Layers, and less complex organisms grow from fewer than 3 layers. This topic is discussed further in the Brain Attributes page.

Left and Right brain hemisphere attributes

***Note: Much of the brain illustration shown above was adapted from page 106 of Dean Falk's book entitled "Brain Dance," 1992.

3-patterned formula to brain hemisphere attributes:

When we look at the assigned culturally recognized attributes of the brain, we can see a distinct (over-lapping) 1-patterned, or 2-patterned, or 3-patterned arrangement:a

Left Hemisphere
(Predominantly 3-patterned)


Major Premise
Minor Premise

Time Sequencing:
Past~ Present~Future


Right Body Side:
Tri-cuspid heart valve
Three-lobed lung
Right Hemisphere
(Predominantly 2-patterned)

Macro versus Micro
Whole versus Part
Inner versus Outer

Major Scale vs Minor Scale
Loud versus Soft (Quiet)
Consonance vs Dissonance

Visuospatial: (Art)
Background vs Foreground
Light vs Dark (Contrasts)
1 Dimension vs 2 Dimensions

Pain versus Pleasure
Positive vs Negative
Love versus Hate

Left Body Side:
Bi-cuspid heart valve
Two-lobed lung
Human Heart

The correlations of two and three being made on this page are not typical considerations. However, I did come across a single reference concerning the tricuspid valve:
--- Why does the right side of the heart have a TRICUSPID valve? ---

Human Lungs

In recognizing that the left lung is smaller than the right lung (which provides room for the heart), let us conjecture that this is due to some past earlier developmental sequence just as we find the 1-layer, 2-layer, 3-layer sequential development of the 3 primordial germ layers (Ectoderm- Mesoderm- Entoderm) in primitive to more complex organisms. Hence, difference in size (dimorphism) as well as a two/ or three prominence may provide another link towards understanding developmental processes. Does this mean that the recurring smallness of the female to the male in many species indicates that females came before the male in terms of species-specific evolutionary development during particular environmental circumstances? If so, will there be an increased development towards a 3 to 1 "fusion" ratio?

In ancient times, it was once thought that a male child was generated from the right testicle and a female child from the left testicle. This right side = male and left side = female is in keeping with the cross-referencing pattern related to brain hemisphere functioning controlling the opposite side of the body, as seen when a person has a stroke.

(Predominantly 1-Patterned)

(Self)-Preservation~ (Self)-Procreation~ (Self)-Preeminence

Some additional two-patterned references found in music:
  • Tension and Release
  • Staccato and Legato
  • Slow and Fast
  • Ascending and Descending

An analogy to the above 3 divisions (Reptilian~ Mammalian~ Neo(New)-Mammalian) can be made with the ancient view of the world once held by Nordic peoples who thought the three roots and three limbs of the Yggdrasil tree held Earth, Hell, and Heaven together. In their own way, they were illustrating a fundamental organizational structure of the brain that matures along a 1~ 2~ 3 maturational development sequence. It is because of this underlying basic formula that humans tend to organize world views in a three-patterned manner, in singular and multiple representations thereof.

For those of you who have a penchant for taking the obvious for granted, please note that the Nordic peoples are part of the Indo-European family, and it is this (3rd born) family, moreso than (2nd born) Asians and (1st born) Africans which has the greatest proclivity for developing three-patterned views of the world:

Yggdrasil tree

Note: When we use the left hemisphere attribute "analysis" to define qualities of the right hemisphere, we often-times assign an additional third criteria in one form or another. When we use the right hemisphere attribute 'viewing' (recognizing) to define qualities of the left hemisphere, we often-times alter the 3-part descriptions into 2-part 'portraits'. For example, (generally speaking):

Left "analyzing" Right: Holistic may acquire the additional term "Synergy" or "Unity"; Music can develop a Triadic structure; Art acquires a 3rd dimension and 3-color (trichromatic) theory; Emotion is assigned words such as Compassion, Patience, and Empathy.

Right "viewing" Left: Math may be seen as Give & Take; Logic may become a Mind/Body dichotomy; Time is related to Life & Death; Language is perceived as High & Low pitch.

Left "analyzing" Reptilian attributes may develop three criteria which distinguish a (3 in 1) singular nature, such as arousal, motivation, and emotion.

Right "viewing" Reptilian attributes may picture the basic drives as the seat of emotion whereby a type of kinship alliance is formulated in order to maintain the idea of a dual brain by not permitting the "Reptilian Brain" a separate entity status.

In adding to the above, we could include the following remarks (taken out of their original context because they are related to the present discussion):

"To further complicate the process, it has been suggested that we have 3 major components in our brain function - instinct, emotion, and intellect. The 3 layers of function correspond to the major layers of brain matter that have been added as we evolved through various stages. Evolution didn't throw much away as humans evolved - our brains have added new layers on top of what was already there instead of the more difficult total restructuring or replacement. We still harbor a primitive reptilian brain at our cores that runs a lot of our subconscious systems like digestion, respiration and circulation. Along the way we picked up a number of only marginally compatible and integrated layers, evolving our conscious minds only with the addition of the outermost layer."

--- Perception and Behavior --- by Kort E Patterson

Your Questions, Comments or Additional Information are welcomed:
Herb O. Buckland