The Neuroscience of Personality

[ooo]

Last week I received my copy of "The Neuroscience of Personality", Dario Nardi's book about his MBTI researches. This book has many merits, first of which is that it's the first study conducted to prove the typology theories, and in doing so it uses scientifical engines (EEG[1]) that allow us to have a real view of the most important thing involved in psychology: the mechanism of our brains.

I'll be glad to share the saucy things I've discovered with you, in the hope of reaching new insights and drop some theoretical stereotypes that in the end help no one, and I believe just can cause hate and damage.

By analyzing this, you'll see that both MBTI and Socionics offer good perspectives, but they're both flawed in some parts; possibly it's by the combination of the 2 that some steps ahead will be realized. Let's start.

The neocortex can be divided in around 16 regions, Prefrontal (Fp), Frontal (F), Temporal (T), Parietal (C, P), and Occipital (O); each of these regions is further divided for the left and right hemispheres.

Fp1: Chief Judge
Fp2: Process Manager
F7: Imaginative Mimic
F3: Deductive Analyst
F4: Expert Classifier
F8: Grounded Believer
T3: Precise Speaker
C3: Factual Storekeeper
T4: Intuitive Listener
C4: Flowing Artist
T5: Sensitive Mediator
P3: Tactical Navigator
P4: Strategic Gamer
T6: Purposeful Futurist
O1: Visual Engineer
O2: Abstract Impressionist

Each MBTI type analyzed followed recurring patterns in the brain activity, in common with the individuals of the same type.
Here's how each brain alights according to types:


The colors show in blue the regions most used, in light blue the commonly used, in grey the ones still used in some occasions, and in black the ones almost left unused.

The first thing that we can notice when looking at the EEG scans is about the P/J dichotomy; all the types that use a dominant rational function, either extroverted or introverted, show a higher activity in the Fp1 area. Translating MBTI terms in Socionics, this means that the MBTI IP types are actually J types, confirming the "infamous" J/P switch for the introverts.

The entire Prefrontal region is nevertheless used by all the types in a significant amount, and both Fp1 and Fp2 result as greatly used, in particular, this is how much each type favors Fp1 and Fp2:

ISFP: Fp1 68%, Fp2 32%
ENFJ: Fp1 63%, Fp2 37%
ENTJ: Fp1 63%, Fp2 37%
ISTP: Fp1 59%, Fp2 41%
INFP: Fp1 52%, Fp2 48%
ESFJ: Fp1 52%, Fp2 48%
ESTJ: Fp1 52%, Fp2 48%
INTP: Fp1 51%, Fp2 49%
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INFJ: Fp1 49%, Fp2 51%
ENTP: Fp1 48%, Fp2 52%
ENFP: Fp1 48%, Fp2 52%
INTJ: Fp1 48%, Fp2 52%
ESFP: Fp1 48%, Fp2 52%
ISTJ: Fp1 47%, Fp2 53%
ESTP: Fp1 46%, Fp2 54%
ISFJ: Fp1 45%, Fp2 55%

Translating all these results into Socionics we'll have that Rationals rely on Fp1, while Irrationals rely more on Fp2.

What distinguishes the Introverts from the Extroverts is, in general, a greater activity in the frontal part for the Extroverts, while Introverts tend to use more the regions in the back of the brain; anyway, this is not a rule and there are different exceptions.

Another important dichotomy that shows through the scans is that Sensory types tend to use more the left regions (analytic), and Intuitive types use more right regions (holistic).

Thinking types show more activity in the regions of reasoning ( F3, F4, P3, P4 ); Feeling types have more access to C4, whereas Thinking types use C3 more.

Although we can identify the regions of the brains and ascribe them to the main functions of each type, we can't assign a cognitive process to those regions. For example, region F7 handles several functions including mimicking others' behaviors, asking "what if?" and drawing conclusions based on context. These elements sound like the definition of Extraverted Intuition, but most people show some activity in this same region, and this doesn't mean that most of them use Extraverted Intuition. An important consideration to make is that brain activity does not equal behavior/preferences. An example to this is that most people who enjoy brainstorming activities do not show the holistic Christmas tree pattern that is typical of Ne types and that shine at trans-contextual thinking [see below].
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Further on, every type uses some region in common with his "opposite" type. An ISFP (FiSe) relies on some of the same regions used by an INTJ (NiTe) or an ENTJ (TeNi), and this happens for every type with the same modalities we find for the Socionics organization of the quadras, confirming like this both the quadras of Socionics and the J/P switch again.

Another interesting thing happens when we look at the brains of an INFP (FiNe) and an ESTP (SeTi), they are complementary. This last point raises some questions: 1) Are they duals? 2) Why does the duality theory used in socionics give the greatest importance to matching rationals with rationals and irrationals with irrationals, over every other dichotomy (and isn't this against a duality-complementary theory itself?)? 3) Does this mean that when switching to socionics, EIIs will naturally complete SLEs, and so forth for everybody else?

It's interesting even to notice that the INFP and ESTP brains are the only ones to be perfectly complementary.

Something to ponder on.



[1]EEG, or electroencephalogram, involves the recording of spontaneous electrical activity along the scalp produced by the firing of neurons within the outer layer of the brain, the neurocortex, associated with numerous cognitive functions including language, memory, thought and consciousness. Although EEG cannot delve into the middle or deep layers of the brain, those deeper cognitive functions can still be detected by the activity in the neocortex.


Notes-
58 subjects were used for the final results published in the book, but many more have been analyzed, in the arc of 5 years, from 2006 to 2011. All the subjects were selected among the students of the UCLA, they were 18-25, healthy and with an usually high IQ. All the subjects were self-typed, and only the subjects who had no doubts about their MBTI type have been tested.
The test lasted several hours and different activities, from meditation to writing, to speed-date, were performed while the subjects were wearing their EEG cap.
Up to today, the results have not been debunked by Dario Nardi, or anyone else.

Dario Nardi's test still remains one of the most accurate assessments for the Junghian elements.