When
we took the personality test at the beginning of the semester, I knew without a
doubt that the first letter would be an I for introversion. The other letters might change
depending on my mood that day, but the introversion aspect always remains the same. Other people might have known with
certainty that they would be categorized as extroverts, and still others might
have been unsure of their classification.
Personality tests are by no means 100% accurate all of the time, but
they can provide some generally useful information. For example, how people interact in a group can be based in
part on personality types. Knowing
people’s strengths and weaknesses beforehand can improve the overall efficiency
of the group.
There are certainly a lot of
factors that contribute to an individual’s personality type, a nature/nurture
dynamic that often gets discussed when analyzing someone’s behaviors and
actions. I found some interesting
research done on dopamine and its relation to extroversion. Dopamine is usually associated with
being a neurotransmitter in the brain involved in a variety of different
signaling pathways, including reward motivated behavior (Baik 2013). In terms of how this relates to
personality, studies have been done that look at dopamine sensitivity in
individuals identified as extroverted or introverted. Extroverted individuals are believed to have higher dopamine
sensitivity when it comes to rewards resulting in what could be described as a
more intense feeling when achieving some sort of goal. One particular study looked at MRI data
from extroverts and introverts to observe how different regions of the brain
responded to a gambling/reward scenario. The researchers concluded that individuals identified as
extroverts demonstrated “increased activation in reward-sensitive regions when
receiving rewards” (Cohen 2005). This
type of positive reinforcement could potentially influence reward-seeking
behaviors and encourage the taking of more risks in search for external
gratification.
Obviously dopamine alone cannot be
solely attributed to why certain people are considered extroverts and others
introverts. There are many shades
of gray even when categorizing people based on their personalities. It is interesting to consider, however, the
different physiological mechanisms that influence our behaviors and how we
interact with one another.
Baik JH. Oct. 2013. Dopamine signaling in reward-related
behaviors. Frontiers in Neural Circuits 7: 152.
Cohen MX, Young J, Baek JM, Kessler C, Ranganath C. Nov.
2005. Individual differences in extraversion and dopamine genetics predict
neural reward responses. Cognitive Brain Research 25: 851-861.
Last semester I had the privilege of taking Psychology of Personality at Regis University. I was able to learn so much about myself as well as recognize certain traits in others. After taking that course, I can concur that personality is multifaceted! What I enjoyed the most about that course was learning about the BIG 5 personality traits. You have already mentioned one, the spectrum of extroversion. The other traits are neuroticism, openness to experience, consciousness, and agreeableness. These traits can easily be remembered by thinking of the words OCEAN or CANOE. One should always remember that these traits all lie on a spectrum. Thus, you will either score high, midline, or low on each of the five traits. Additionally, just because you score high on one trait does not indicate you will score high or low on another. This individual array of scoring on these spectrums is what makes personality so different and yet quite similar!
ReplyDeleteHi Seella,
ReplyDeleteFirst off, I like this post. I've always been interested in the scientific side of personality. It's weird to me that we can all be classified into specific categories based on our physiology.
My first thought about this post is rooted in our lecture. As you probably have noted from our lecture, the response to a neurotransmitter depends on what type of messenger system is coupled with the receptor in question. I wonder, is it that introverted people have less of a certain variety of g-protein receptors associated with dopamine than our extroverted companions?
Seella,
ReplyDeleteThat was a great article. As an introvert, I have always been curious what kind of biology is behind personality. Ben's question also made me think about how intricate these outward expressions of personality are, even down to a neurotransmitter receptor. After researching, I found an article by Wacker et al. that found differences in brain activity based on extroversion and dopamine receptors. It is amazing to think about how many details come together to form personality!
Wacker J, Chavanon M, Stemmler G. Investigating the dopaminergic basis of extraversion in humans: a multilevel approach. Journal of Personality and Social Psychology. 91(1): 171-187, 2006.