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Current time:0:00Total duration:5:33

Video transcript

alright let's talk about yet another theory of personality called the biologic theory but let me first start off by saying that there are many variations to this theory some relate more specifically to the brain and others like the evolutionary approach the evolutionary psychology approach is more concerned with behavior rather than treats so for example the evolutionary psychology theorizes that males and females have different meeting strategies that influence the costs associated with passing on genetic material such as our for example men have lots of sexual partners but women are more selective due to the costs of pregnancy now this case I just said is probably the most dominant psychological and biological theory to date and bus is one of the major psychologists associated with it now taking all of this aside the biologic theory suggests that important components of personality are inherited so that's the keyword important components are inherited or determined in part by our genes and I'm not talking about those things we wear but I'm talking about the things that are buried deep within our cells nucleus and to study biologic and genetic effects on personality researchers always turn to look at twins because twin studies are used in many psychological theories to tease out environmental versus genetic characteristics now more specifically they look at identical twins and that's because they have the same genetic makeup so that will eliminate one factor of variation so look at identical twins who were raised apart from each other or in different environments now results show that even though the twins were reared separately at an early age they still had similar personalities certain traits that we give credit to the trait theory for categorizing were more influenced by heredity than others were in one example is the social potency trait in social potency is the degree to which a person assumes leadership and mastery roles in a social situation so this was found to be common in both twins that were raised separately and another trait called traditionalism which is the tendency to follow Authority was also shown to be common with both twins but at the same time there were other trades that had weaker genetic components and some examples of this is the tree of achievement it was stronger and one twin versus another and same with closeness so some researchers have even gone further to look at specific genes to try and relate to our personality one example is that people with a longer dopamine 4 receptor gene are more likely to be thrill-seekers so basically if you have this gene you may love roller coasters and probably want to skydive one day hey that sounds a lot like me no but don't think that just because you have a gene you're destined to have that personality we all know that so just because you have a longer dopamine 4 receptor gene doesn't mean you will be a thrill seeker for sure there are a lot of other things such as environmental factors that are coupled with genes that account for variation like looking back at this case of the identical twins obviously there were parts of their personality that we can attribute to how they were reared and differences in their environment growing up now another key word to know with this theory and many other theories is the word temperament now temperament is an innate disposition and that's why I bring it up with the biologic theory because of that word innate and it usually means brought up by genetics or it's inherited so temperament is anything from our mood to our activity level and it's usually consistent throughout our life and temperament is not solely just associated with the biologic theory it's also associated with several other theories including the trait theory so biologic principles can underlie important concepts in many personality theories so overall important takeaway of this tutorial is that our inherited genes to some degree lead to our traits which then in turn lead to our behavior or our personality but this isn't an end-all be-all relationship our genes don't always determine our total personality there has to be other things that account for this and that includes environmental factors