According to the Lilienfeld text, results from a University of Minnesota study show that genes play a big role in personality. Researchers at the U of M collected a sample of 130 identical and fraternal twins that grew up apart. It was found that identical twins reared apart tend to be very similar in their personality traits. They're also a lot more similar than fraternal twins reared apart. When compared with twins that grew up together, it's shown that identical twins grown up apart are about as similar as identical twins grown up together- suggesting that shared environment plays little or no role in adult personality. Although shared environment plays some role in childhood personality, this role generally subsides as we grow older. This is important to understand, because although there may be some studies showing that shared environment has a big impact- you should check to see whether they were studying children or adults, since as we grow older the connection between environment and personality is generally lost. Something I wonder about is how big of an impact genes have on personality when looking at siblings, not just twins? Would there be any correlation between genes and personality with siblings that grew up separately? Would the environment play a bigger role, since unlike twins, siblings do not share all the same genetic material? Would HOW siblings are being raised have a bigger impact?
chav0084: November 2011 Archives
In an article by David Womack, he focuses on smiling. He mentions how at the artificial intelligence lab at MIT, researchers are engaged in understanding the relationship between facial expressions and emotional states for the purpose of creating advanced robot interfaces. Ironically, the fact that computers do not have to feel the emotions they display gives them a big advantage. Smiles are not all created equal. A true or zygomatic smile requires the contraction of special zygomaticus muscles in the face that are directly linked to the cerebral cortex. The close connection between these muscles and emotion means that a zygomatic smile is very difficult to fake. Humans are also very good at detecting false smiles. We can tell from a young age when people are "faking it." According to the facial feedback hypothesis, you're likely to feel emotions that correspond to your facial features. So if you are smiling, then you are more likely to feel happy. One finding that supports the facial feedback hypothesis is the cartoon study that we did for psych discussion. People were instructed watch cartoons holding a pencil in their mouths, either between their lips or between their teeth. People with the pencils in their lips were therefore prevented from smiling. It turned out that the people with the pencils in their teeth, who could smile, rated cartoons funnier than those who could not. Although there are studies such as this one that support the hypothesis, it's not certain that these effects work by means of facial feedback to the brain. This is a problem with ruling out rival hypotheses- these effects can be explained by other things, such as classical conditioning.
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