Cognition: Thinking, Intelligence, and Language 295development (Trzaskowski et al., 2014; von Stumm & Plomin, 2015). Some observations
suggest IQ scores are steadily increasing over time, from generation to generation, in
modernized countries, a phenomenon called the Flynn effect (Flynn, 2009).
THINKING CRITICALLYHow might you determine whether flute-playing ability is a highly heritable trait? If you want to
improve your flute playing and someone tells you that musical ability is heritable, should you stop
practicing?
The response entered here will be saved to your notes and may be
collected by your instructor if he/she requires it.SubmitTHE BELL CURVE AND MISINTERPRETATION OF STATISTICS One of the other factors
that has been examined for possible heritable differences in performance on IQ tests
is the concept of race. (The term race is used in most of these investigations as a way
to group people with common skin colors or facial features, and one should always
be mindful of how suspect that kind of classification is. Cultural background, educa-
tional experiences, and socioeconomic factors typically have far more to do with sim-
ilarities in group performances than does the color of one’s skin.) In 1994, Herrnstein
and Murray published the controversial book The Bell Curve, in which they cite large
numbers of statistical studies (never published in scientific journals prior to the book)
that led them to make the claim that IQ is largely inherited. These authors go further
by also implying that people from lower economic levels are poor because they are
unintelligent.
In their book, Herrnstein and Murray made several statistical errors and ignored the
effects of environment and culture. First, they assumed that IQ tests actually do measure
intelligence. As discussed earlier, IQ tests are not free of cultural or socioeconomic bias. Fur-
thermore, as the video Intelligence Tests and Stereotypes explains, just being aware of nega-
tive stereotypes can result in an individual scoring poorly on intelligence tests, a response
called stereotype threat (Steele & Aronson, 1995). So all they really found was a correlation
stereotype threat
condition in which being made aware
of a negative performance stereotype
interferes with the performance of
someone that considers himself or
Watch the Video Intelligence Tests and Stereotypes herself part of that group.CC