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Current time:0:00Total duration:7:58

Video transcript

you've probably heard of IQ which means intelligence quotient you may even have taken an intelligence test which is supposed to measure how intelligent you are but what does intelligence mean for a term that's used so widely we have kind of a hard time defining it does it mean street smarts book smarts creativity psychologists even though they still have some disagreements tend to define intelligence as a mental quality allowing you to learn from experience solve problems and use your knowledge to adapt to new situations intelligence tests use numerical scores to measure your aptitude for those types of tasks and compare them to how well other people do so if intelligence is made up of different aptitudes then is it multiple abilities or is it just one one theory is that there's just one general intelligence evidence to support this theory comes from the fact that people who score really well in one type of test such as verbal ability also tend to score really well and other types of tests such as math now you might be better at one of these categories than the other relative to yourself but relative to other people you probably have about the same level of skills in both areas the factor underlying these consistent abilities is referred to as the G factor you can think of G for general intelligence although there's some good evidence for G there's also some support for theories of multiple intelligences a psychologist named Robert Sternberg proposed a theory of three main types of intelligence analytical intelligence what we might think of as academic abilities are the ability to solve well-defined problems creative intelligence the ability to react adaptively to new situations and to generate novel ideas and practical intelligence the ability to solve ill-defined problems such as how to get that book case of the curvy staircase into your apartment when someone tells you their IQ school or what they're really telling you is they're analytical intelligence the scores are scaled so that an average person's score is 100 so depending on where you are in relation to 100 you can tell how you compare to the population at large you may be wondering how intelligence affects people's lives obviously people with high analytical intelligence tend to do well in school however people who score high on any of the intelligence skills we've mentioned so far don't really tend to have better marriages raise their kids better or achieve greater mental and physical well-being than people who score lower for this reason another psychologist proposed that there's another type of intelligence called emotional intelligence this ability helps you perceive understand manage and use emotions in your interactions with others yet another way of thinking about intelligence is in terms of two major categories fluid intelligence and crystallized intelligence fluid intelligence is our ability to reason quickly and abstractly such as when we're solving novel logic problems crystallized intelligence on the other hand refers to our accumulated knowledge and verbal skills the main difference here is that fluid intelligence tends to decrease as we move into older adulthood whereas crystallized intelligence tends to increase or stay the same with all this talk about different definitions of intelligence you are probably wondering how it ever gets measured interestingly the first person to develop an intelligence test actually didn't even mean for it to be an intelligence test alfred Binet was just trying to establish a child's mental age in order to measure children's intellectual development and predict how well they would do in school later on a psychologist at Stanford University modified Benes original test and extended it to teenagers and adults one thing that the Stanford psychologist noticed was that Benes original test items which were originally designed for French children didn't seem very predictive of California children's abilities after he modified the test and for we people forgot about that difference and started using the new version to judge how generally intelligent immigrants coming into the US were now you can probably see the problem with that even from just a language perspective if a test is trying to measure verbal ability then you might be able to do just fine in your native language but it's a lot harder in a language you don't know since then more pans have been taken to try to make intelligence tests more applicable to people from all different cultures but it's an ongoing issue one last consideration that's inherent in any question of traits or talents but particularly popular with intelligence is the question of nature versus nurture that is how much is intelligence due to your genes and how much is due to your environment another experience we study this question by looking at heritability which is the proportion of variability in a trait that's due to genes specifically we usually study hair ability with twin and adoption studies meaning we look at the correlation between intelligence scores and identical twins to people with the exact same genes who grew up in different environments we also look at the correlation in scores between identical twins raised together as well as the correlation and scores between fraternal twins raised together since we have a mix of same in different genes and environment we compare those correlations and try to determine what proportion of the variability in those scores we can attribute to genes and what proportion is attributable to the environment what we know from these studies is that of those three groups there's the strongest correlation and IQ scores between identical twins raised together that alone doesn't really tell us about any differences between nature and nurture though so let's keep going identical twins raised apart still have a high correlation but not as high suggesting some environmental influence on intelligence fraternal twins raised together have an even lower correlation though suggesting that there is also a genetic component so the short answer is both nature and nurture contribute to intelligence since we tend to have more control over the nurture aspect than the nature aspect there's been a lot of research into what types of environments promote intelligence especially for children interestingly although we know some environmental situations that impair normal cognitive functioning there's no recipe for structuring an environment to make a genius when children are deprived of exposure to language or interaction with people their intellectual development is impaired however there's not a direct relationship tons and tons of language exposure helps a child compared to no exposure but it doesn't necessarily make that child a genius perhaps even more important than just intelligence score is your attitude toward intelligence some people have what's called a fixed mindset they think that intelligence is biologically set and unchanging others have what's called a growth mindset meaning that they think intelligence is changeable if you learn more people with a growth mindset tend to be more motivated and able to accomplish more in their careers than people with a fixed mindset so whatever your IQ score is or isn't try to keep in mind that you can always grow and always learn