Biological Introversion/Extraversion

[INTJMom]

Well, I learned about the Biological model of I/E in my Theories of Personality class. I asked my teacher how well it related to Jung's version and she told me that there was some overlap but overall it is an unexplored area. So I thought I would do some casual exploration...

Basically, I's are more quickly and strongly aroused when exposed to external stimulation. Introverts are also more easily overwhelmed by the stimulation of parties, loud music, or social gatherings while extraverts find this kind of stimulation pleasant. On the other end of the coin, extraverts are quickly bored by slow-moving movie plots and soft music while introverts often find these subtle sources of stimulation engaging. When trying to study in a library, research has found that introverts typically will pick quiet study rooms away from all stimulation while extraverts prefer to sit out in the open amidst the stimulation.

Another difference, according to the biological model, is that extraverts are much more sensitive to the idea of rewards. This leads to impulsive behavior which makes them more likely to be found on a roller coaster or at a party. However, this also means that if an extravert thought going on a walk alone would be pleasing, they would be more likely than an introvert to actually do it.

Although I do not wish to address this piece of information as I do the others, research in the biological approach has found that extraverts are happier. This is, in short, due to their ability to appreciate and pursue social experience (commonly found to be a key factor in overall happiness) and their ability to appreciate rewards. As far as rewards go, research has found that extraverts are more pleased with their own accomplishments than introverts, and do not react as badly to failure as introverts. (Of course the problem I see with this is that social experience and rewards do not even begin to describe what constitutes happiness. These two things are items that are measurable by experimentation while I'm sure at least some of the things introverts find happiness in are not as easily measurable. I personally don't see happy as something experienced but rather something obtained.)

So, in summary: Introverts are much more sensitive to stimulation than extraverts.

So, I wish just wondering if whoever reads this feels like it is in some way descriptive of their MBTI I/E preference? I personally feel like the biological model of an introvert fits me well.

Thanks.

I think these descriptions fit the MBTT models well.

I agree with you about the happiness thing.

 

[wedekit]

I know you don't want to really go into this one, but what makes you believe 'happiness' is something someone must achieve, or obtain?

Because personally, I consider myself a 'happy person'. I wake up on an ordinary day, and my default mood is, at least, 'pleasant', and most of the time the rest of my day I feel 'happy' (although exactly what 'happy' is depends on who's talking about it - here I mean something along the lines of a 'pleasant contentness'). I haven't done anything to achieve this, I just am.

I'd be curious to know what your definition of happiness is, what your normal state of being is, and how one goes about achieving 'happiness'?

Happiness for me is satisfaction in all aspects of my life. I agree that happiness depends on who is talking about it. We all have different ideas, and I'm sure in one way or another we are all correct. By working towards my goals and looking with hope to the future I consider myself a happy person. By carefully exploring who I am as a person and making choices that reflect who I wish to be, I consider myself living a happy life; even if at that moment I am not a happy person.

I know you said you don't wish to address this as much as the rest but, to me, it is critically important. These ascertions are so invalid that I have to question all the rest that went before it in the testing. It smacks of major subjectivity, thus, indicating the rest may not be that objective. Happiness or lack of it is based on social activity? As a "biological introvert," I strongly disagree. Happiness is a by-product of actualizing choices. As for "rewards," stated as pertaining to I/E... to me its a matter of quantity vs quality. I find the extrovert less intense. Their experience more diffuse. Example: Strong background activity or loud background noise while conversing with multiple people disallows biological/mental intense focus on any of them.... preferred by the extrovert as "energizing." For an introvert, these are described as "distracting" implying a desire for intense focus. Following that line of thought, what an introvert experiences has more intensity and that includes happiness. Abundance is offset by a deeper experience of less. Therefore, I would say, they are equal but arrived at differently.

All of what I stated comes directly from a text book called "Theories of Personality", so I assume that even though it is subjective it is a prominent theory within the field of Psychology. It was a subsection within the Biological I/E approach that discussed that extraverts test (through experimentation) as happier than introverts. It's not my opinion. It's the opinion of the experimenters.

I imagine past surveys asked people about different aspects of their life (i.e. social activity and response to rewards) and then asked them to rate their happiness on a scale 1 to 10. People probably consistently rated themselves happier when they also rated social activity and positive responses to rewards high. They are just going with what they can at least show evidence for. They can't state anything they don't have evidence for without losing all credibility, and since they made it into a text book chapter I would assume that they do have adequate evidence to say what they have. Plenty of people probably don't agree with what they claim to have found (including me), but they can't deny these claims because they use the same kind of statistical testing all psychologists use and they have come up with significant results. That's all that can be said.

I honestly think I should have omitted that part from my post.

 

[ygolo]

Is it possible that someone can "switch" part way through life? (Not on purpose, mind you)

Can someone be a biological introvert or extrovert for most of their life, and due to long-term illness (or recovering from long-term illness or some other long-term change in biochemistry) switch to being the other?

 

[Thursday]

hmm
i hate listening to music on a stereo
but in my headphones its the best

i heard introverts have a problem with facial expressions.....
but i am very good with them and conveying emotions with them

is that more of a bodily intelligence thing, being aware of one's self, or what ?

and i heard introverts don't have a lot of energy,yet i have a surplus
whats up with that ?

 

[Wandering]

Basically, I's are more quickly and strongly aroused when exposed to external stimulation. Introverts are also more easily overwhelmed by the stimulation of parties, loud music, or social gatherings while extraverts find this kind of stimulation pleasant. On the other end of the coin, extraverts are quickly bored by slow-moving movie plots and soft music while introverts often find these subtle sources of stimulation engaging.

According to this, I (INFJ) am more biologically Extraverted than my ENFJ husband Not that I'm very biologically extraverted, but he's very strongly b. introverted - except when he gets into a B.E. mood, like when he's jamming with friends, in which case he will love loud noises and music and social gatherings. But the rest of the time, those things completely overwhelm him, to the point of making him physically ill and/or mentally depressed.

Another difference, according to the biological model, is that extraverts are much more sensitive to the idea of rewards. This leads to impulsive behavior which makes them more likely to be found on a roller coaster or at a party. However, this also means that if an extravert thought going on a walk alone would be pleasing, they would be more likely than an introvert to actually do it.

On this point, my husband would be the B.E. one while I'd be the B.I. one. Rewards don't motivate me one bit, that's even a major problem in my life, but they do somewhat motivate him.

As far as rewards go, research has found that extraverts are more pleased with their own accomplishments than introverts, and do not react as badly to failure as introverts.

And here we go back to me being the B.E. one: my husband reacts very badly to failure or even to *perceived* failure, and he always seems shy/reluctant to genuinely appreciate his own accomplishments as though he didn't actually do anything really worthwhile. I'm always having to tell him that he did do great and that he should feel proud of what he accomplished.

 

[Seanan]

All of what I stated comes directly from a text book called "Theories of Personality", so I assume that even though it is subjective it is a prominent theory within the field of Psychology. It was a subsection within the Biological I/E approach that discussed that extraverts test (through experimentation) as happier than introverts. It's not my opinion. It's the opinion of the experimenters.

I imagine past surveys asked people about different aspects of their life (i.e. social activity and response to rewards) and then asked them to rate their happiness on a scale 1 to 10. People probably consistently rated themselves happier when they also rated social activity and positive responses to rewards high. They are just going with what they can at least show evidence for. They can't state anything they don't have evidence for without losing all credibility, and since they made it into a text book chapter I would assume that they do have adequate evidence to say what they have. Plenty of people probably don't agree with what they claim to have found (including me), but they can't deny these claims because they use the same kind of statistical testing all psychologists use and they have come up with significant results. That's all that can be said.

I honestly think I should have omitted that part from my post.

Thanks Wedekit (sp?) I guess that's why I've seen opinions, statistical and scientific "proofs" change so often and much of it is diametrically opposed to another. Much of society is putting little stock in it anymore as a result. I'm not sure of all the reasons why this happens but do know internal "politics" is often involved. And, of course, it seems to happen most in the rather subjective field of psychology. Anyone who has raised kids and kept up with the prevailing "research" on that can attest the changes.... each with their "sound" backup.

 

[Little Buddha]

I'm currently writing an article about introversion/extraversion based on results of neuropsychological research and the results have now generated strong evidence. The biological basis for I/E seems to have something to do with cortical arousal, more specific the level of dopamine in the cortex. Researchers claim that introverts have a naturally higher level of dopamine i the cortex and thus have a lower threshold for stimuli (especially noise and visual stimuli) before getting dopamine overloaded. This may come through as sensitivity towards loud noises and visually messy places (i.e. shopping malls).

As a biological introvert I very easily get overwhelmed by places with lots of people (i.e. a shopping mall, a discotheque or Cairo) generating uncontrolled movements, assymetrical noises and numeral visual stimulants.
This renders me in a state of total confusion and subsequently results in fatigue if I stay in places like that for too long.
After an experience like that I normally regenrate by lying flat on the bed starring at the ceiling and staying totally and utterly self absorbed for a long time.

Regarding the extraverts staying home rather than go to a party I guess it's got to do with what kind of intellectual stimulation you find among a bunch of drunk people and thus lies beyond the biological I/E question.
My boyfriend, an ENTP, feels the same way about parties thus seeking stimulation in what generates new ideas and creativity in his mind (this might include staying home saturday night writing or reading), rather than wasting time on superficial unsatisfying conversations.

I think "happiness" is such a complex idea. It's strictly subjective and I guess one must achieve happiness in pursuing his own values.
For instance, if someone finds happiness in reading the newspaper he could experience happiness on a daily basis. If someone finds happiness in personal freedom, it might be more difficult to achieve when you have an obligation to work, daily necessary routines etc.

 

[Eric B]

That's very interesting, and makes a lot of sense. Introversion and extraversion seem to be driven by needs that are are "hard wired" into the brain, as apart of the rest of the chemistry of the brain that shapes who a person is. The other scales of People/Task-orientation and Cooperative/Pragmatic (which tie in with T/F and J/P) would stem from this as well.

 

[Little Buddha]

Oh, another point: There are some inconsistency among researchers in the field of neuroscience and personality. Roughly you can group them into neuropsychologists and neurogeneticists.
The former focuses mainly on taskperformance (including behaviour studies) combined with physiological measurements (i.e. salivation, heart rate, perspiration, brain blood flow, brain waves) whereas the latter focuses mainly on genetic analyses (mapping and defining genes) combined with questionnaires on whether you like parties, being social and so on.

This results in different discourses among the research groups, which then again makes it somewhat difficult to compare and combine the research results generated by the two groups. The results often get mixed up in the public because reporters or other intermediaries often don't recognize this relation.
One thing though they both agree upon is that it's got something to with dopamine levels.

Personally I prefer the neuropsychologist view because it is by far the most objective way of studying I/E. They rarely involve the opinions of the tested person thus more or less minimizing subjectivity in the test results.

So I guess, what I want to say is that the questions about attending parties, being happy, reactions to reward, liking or disliking fast music or generally how you feel about something and so on leaves little evidence, as some of the comments posted previously clearly indicates.

Ps. I'm very much an introvert but I also like death metal.

 

[GZA]

Thats very interesting... I'll reread it and comment more later. I do think I probably don't go for things as fearlessly as many people, and it may be due to introvertedness (or possibly a host of other factors). I'm working on fixing it though.

 

[Seanan]

Thats very interesting... I'll reread it and comment more later. I do think I probably don't go for things as fearlessly as many people, and it may be due to introvertedness (or possibly a host of other factors). I'm working on fixing it though.

When you say "fearless" are you just referring to "shyness" in social situations? I don't think that's the same thing as introversion. I relate very much to the biological aspects of sensory overload, etc. That sensory overload is physically and mentally draining... so any "shyness" is really irrelevant.

 

[spirilis]

I recall a couple years ago finding the website of a Jungian type expert named Katherine Benziger, and one of the articles on her website mentioned this theory in detail based on a study she linked--something to do with sensory sensitivity and the spinal cord I think, with the hint that this may influence one's tendency towards introversion and extroversion. Then her website was totally redone and I lost the links. Now it looks nothing like the previous revisions-- benziger.org (kudos to anyone who finds an article there matching what I just described)

There was another article there which talked about the perils of "falsification of type"... living and playing out roles in your life that are not ideal for your particular personality type, and the kind of anxiety/mental disorders that can be attributed to such.

---
edit: nm, not that hard to find
benziger.org has articles - click the link, go to "More Information" (the site doesn't seem to let you link to its content)

"The Physiology of Type: Introversion and Extroversion"

and for the other one-
"The Physiology of Falsification of Type"
And this is also cool--not sure if I'd seen it before: "The Physiology of Type: Jung's Four Functions"
Wow, this last link is very interesting. I need to make a new post out of this.

 

[GZA]

When you say "fearless" are you just referring to "shyness" in social situations? I don't think that's the same thing as introversion. I relate very much to the biological aspects of sensory overload, etc. That sensory overload is physically and mentally draining... so any "shyness" is really irrelevant.

I agree with you wholeheartedly that shyness and introversion are not the same... that actually might be my number one most disliked misconception about introversion, actually.

I suppose "fearlessly" wasn't the right word. What I mean is that some people I know and just get up and go after something because they are more immersed in the space around them. I am more like an observer, I feel like I'm outside of my surroundings, so I have to kind of break the attachment to really go after something sometimes... Its not neccesarily a social thing, either.

 

[Seanan]

I agree with you wholeheartedly that shyness and introversion are not the same... that actually might be my number one most disliked misconception about introversion, actually.

I suppose "fearlessly" wasn't the right word. What I mean is that some people I know and just get up and go after something because they are more immersed in the space around them. I am more like an observer, I feel like I'm outside of my surroundings, so I have to kind of break the attachment to really go after something sometimes... Its not neccesarily a social thing, either.

I think I know what you mean. For instance, in a crowd or social gathering, I usually see something about to happen when others don't because I'm not immersed in the activities... yes, I'm observing. That has actually protected me in a couple of situations when something really bad happened. Is that it?

 

[Jade Curtiss]

I know you said you don't wish to address this as much as the rest but, to me, it is critically important. These ascertions are so invalid that I have to question all the rest that went before it in the testing. It smacks of major subjectivity, thus, indicating the rest may not be that objective. Happiness or lack of it is based on social activity? As a "biological introvert," I strongly disagree. Happiness is a by-product of actualizing choices. As for "rewards," stated as pertaining to I/E... to me its a matter of quantity vs quality. I find the extrovert less intense. Their experience more diffuse. Example: Strong background activity or loud background noise while conversing with multiple people disallows biological/mental intense focus on any of them.... preferred by the extrovert as "energizing." For an introvert, these are described as "distracting" implying a desire for intense focus. Following that line of thought, what an introvert experiences has more intensity and that includes happiness. Abundance is offset by a deeper experience of less. Therefore, I would say, they are equal but arrived at differently.

Exactly. Introverts receive greater satisfaction from focused, selective endeavors that they can explore in-depth, while extraverts enjoy a variety of stimulating activities without feeling the need to focus too deeply on any one subject. Breadth vs depth and extensive vs intensive are two keyword contrasts between extraversion and introversion. This matter also seems to be affected by P/J preference as well to an extent, with ExxPs/sanguines being the most scattered ("dabblers"), and IxxJs/melancholics being the most focused.

The biological basis for introversion/extraversion is pretty complex, involving several factors, but it certainly exists. The Introvert Advantage by Marti Olsen Laney is an excellent book on introversion that is extremely comprehensive in describing the outer traits of each orientation, and giving advice for introverts on how to manage their life effectively in an extraverted society. One section also goes into detail on the research done on the biological basis for each orientation.

The physiological basis for this aspect of temperament is connected to the D4DR gene, known as the "novelty seeking gene" located on the 11th chromosone. Studies found that self-reported extraverts had longer D4DR genes and were less sensitive to the neurotransmittor dopamine (involved in energy levels, physical activity, alertness, active learning and motivation) meaning they required greater stimulus to satisfy their need for dopamine and adrenaline levels, which increase dopamine. Introverts had shorter D4DR genes which were more sensitive to dopamine and thus didn't require as much excitement to satisfy their needs as extraverts.

Another test had participants injected with tiny amounts of radiation which were monitered and shown to take different pathways through the bloodstream and brain depending the individual's temperement. The introvert's brain showed higher activity levels and the blood took a longer, more complex route through the brain compared to the extravert's. The introverted path traveled through the hippocampus (involved in long-term memory), frontal lobe, and ended at the amygdala while the extraverts ended quickly at the temporal and motor center, which is connected to short-term memory. The extravert's pathway was activated by dopamine while the introvert's was activated by the neurotransmitter acetycholine, which is involved in sustaining a calm and alert feeling, long-term memory, and increases positive feelings when engaged in thinking and reflecting. Acetycholine gives introverts "hap hits" when they can rest in peaceful contemplation.

Extravert's autonomic nervous system was also found to correlate with activation of the sympathetic system (commonly called the "fight or flight" response) while introversion correlated withe the parasympathetic nervous system, a "cool-down" mode where bodily functions relax and digestion occurs. Various other biological responses were connected to each autonomic nervous system, such as pupils dilating or constricting and blood pressure and heart rate increasing or decreasing.

I've also heard there is biological evidence for the P/J difference, which I find interesting because I've always identified most strongly with the Introversion and Percieving preferences, which happen to be the two dichotomies with a (somewhat) proven physiological basis...

 

[Eric B]

Considering that both E/I and J/P are said to be the first letters that develop (become apparent) in a child, that would make sense that they would have biological connections. And while E/I is "expressiveness", which is about the stimulation you [actively] "seek", the other factor would be "responsiveness", which is about how much you [passively] "want", and J/P would figure in that. (Such as being more open vs being more decisive).