Understanding Psychology (10th Ed)

Key Concepts 
Are traditional IQ tests cultur-
ally biased? 
Are there racial diff erences in 
intelligence? 
To what degree is intelligence 
infl uenced by the environ-
ment and to what degree by 
heredity?
M O D U L E 2 8
Group Diff erences in Intelligence: 
Genetic and Environmental 
Determinants 
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 Module 
28 
Group Diff erences in Intelligence: Genetic and Environmental Determinants 
301
For example, the traditional Western value of “rugged individualism” means that 
correct answers to test items may require a test-taker to reason independently of a 
particular social context. In contrast, the African cultural value of communalism, in 
which one’s group is valued more than individuals, may leave test-takers from that 
tradition unable to answer a question that provides no information about the social 
context (Greenfi eld, 1997; Kwate, 2001).
In an attempt to produce a culture-fair IQ test, one that does 
not discriminate against the members of any minority group, 
psychologists have tried to devise test items that assess 
experiences common to all cultures or emphasize questions 
that do not require language usage. However, test makers 
have found this diffi cult to do because past experiences, 
attitudes, and values almost always have an impact on 
respondents’ answers (Fagan & Holland, 2009).
For example, children raised in Western cultures group things on the basis of what 
they are (such as putting dog and fi sh into the category of animal ). In contrast, members 
of the Kpelle tribe in Africa see intelligence demonstrated by grouping things according 
to what they do (grouping fi sh with swim ). Similarly, children in the United States asked 
to memorize the position of objects on a chessboard perform better than African 
children living in remote villages if household objects familiar to the U.S. children are 
used. But if rocks are used instead of household objects, the African children do better. 
In short, it is diffi cult to produce a truly culture-fair test (Sandoval et al., 1998; Serpell, 
2000; Valencia & Suzuki, 2003). 
The efforts of psychologists to produce culture-fair measures of intelligence relate to 
a lingering controversy over differences in intelligence between members of different 
racial and ethnic groups. In attempting to identify whether there are differences 
between such groups, psychologists have had to confront the broader issue of 
determining the relative contribution to intelligence of genetic factors (heredity) and 
experience (environment)—the nature-nurture issue that is one of the basic issues of 
psychology. 
Richard Herrnstein, a psychologist, and Charles Murray, a sociologist, fanned the 
fl ames of the debate with the publication of their book The Bell Curve in the mid-1990s 
(Herrnstein & Murray, 1994). They argued that an analysis of IQ differences between 
whites and blacks demonstrated that although environmental factors played a role, 
there were also basic genetic differences between the two races. They based their 
argument on a number of fi ndings. For instance, on average, whites score 15 points 
higher than blacks on traditional IQ tests even when socioeconomic status (SES) is 
taken into account. According to Herrnstein and Murray, middle- and upper-SES 
blacks score lower than middle- and upper-SES whites, just as lower-SES blacks score 
lower on average than lower-SES whites. Intelligence differences between blacks and 
whites, they concluded, could not be attributed to environmental differences alone.