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MBTI 4 functions-ENFP / ENFJ
SITE: Anatomy of the Brain
DIFFERENCES
Many ACoAs don’t know or understand that males & females really do think / act differently in certain ways – & not just because of social conditioning. Missing this awareness causes a great deal of confusion & frustration in personal, social & business relationships.
Many studies have looked at what happens in the M vs F brain when we act or think about things. While there are all kinds of variations among each gender, & that our early years (with family, religion & culture) does have a profound effect, we start with differences in bio-chemicals (estrogen vs testosterone) & brain wiring.
EXP: When Cher’s ‘daughter’ had his sex change & added testosterone to the hormonal mix, at first Chaz became more argumentative (& assertive), compared to how he had treated his long-term mate until then. (‘Becoming Chaz‘)

✴︎ Research tells us that some social stereotypes are based on actual biology – BUT have nothing to do with over-all intelligence! – only skills, tendencies & preference.
“Every individual can have both M & F characteristics”, but scientists don’t yet know how much each person has of M or F-like patterns of brain connectivity.
And study results do not apply to individuals but rather to the 2 genders as a whole. Broad indicators can be compared to the biological differences between Introverts & Extrovert.
Other M / F differences relate to:
1. Personality TYPES // 2. Family ROLES // 3. Birth ORDER // 4. LEARNING Preferences …..
NOTE: Since variations in human behavior are dealt with in other posts, this series focuses mainly on physical structures.
SEE: “20 M/F Differences, Backed by Science”
Some BRAIN MAPPING studies
• One study at the U of Penn used diffusion-tensor-imaging (DTI) of water molecules in the brain’s white matter, made up of axons – the “wires” that connect neurons. ➡️ Tractographic images of neural connections via DTI
They scanned nearly 1,000 young people (ages 8-22), mapping neural circuitry, showing all the signals that travel like busy road traffic (connectivity) – focused on the 4 hemispheres, (2 cerebrum & 2 cerebellum)
• Psychologist Stuart Ritchie’s research at the U of Edinburgh, MRI-scanned over 5,000 men & women (ages 44-77), drawn from 500,000 participants in the UK Biobank‘s long-term bio-med study. The volume of 68 specific areas were examined, including the thickness of the cerebral cortex (wrinkly outer layer important in consciousness, language, memory, perception…..), white matter, resting state connectivity & cognitive testing.
▪︎ Ruigrok et.al. in Germany, studied 2,186 MRI scans (age range 21–90) for sex differences in grey matter (GM) volume, in many parts of the brain. Neither age nor longer education affected their conclusion – that size & quantity of GM was located in different part of the F & M brains.
• Research at Madrid’s Consejo Superior in Madrid looked at the cortex with stereo-logical correlative light & electron microscopy, searching for which structures may underpin M vs F variations in cognitive function (thinking). Differences were found in the density of synapses, which are the junctions between neu
rons that allow cells to communicate with each other
• A 2013 researchers from UCLA and Universidad Autónoma de Madrid used 3D high-resolution structural brain MRI scans of automated segmentation of the hippocampus. 104 healthy participants (ages 18-27) took a series of IQ tests measuring abstract, verbal & spatial intelligence, along with working memory, executive control, attention & processing speed
• Looking for gender differences re. the prevalence, age of onset, & symptomatology of many neuro-psychiatric conditions, Amber Ruigrok, et.al, at the U of Cambridge in the UK looked at overall brain volume & density, in 6 age-categories (18-59) – of the amygdala, hippocampus, & insula – areas implicated in sex-biased mental illnesses
Male & female brains differ right down to the genetic level. Every male cell contains a Y chromosome, while F brains usually do not. 😾
M & F brains process the same neuro-chemicals, but in different degrees :
▪︎ serotonin – which, among other things, helps us sit still
(Ms are less inclined that Fs)
▪︎ testosterone – the sex & aggression chemical
(Ms tend to be more physically impulsive & aggressive)
▪︎ estrogen – a F growth & reproductive chemical
▪︎ oxytocin – a bonding-relationship chemical……
(Ms process less of it)
▪︎ glucose – for thinking, memory & learning
(Fs ‘burn’ more glucose, so their brains heat up more)
NEXT: M-F brains #2

































