There may be no such thing as a "universal" intelligence test, according to a recent study.

New research from scientists at the University of Granada in Spain suggests that a universal test of intelligence quotient does not exist. Results in this type of test are determined to a strong degree by cultural differences.

For the study, scientists from the University of Grnada's Brain Mind and behavior Research Center conducted a study of 54 individuals aged between 18 and 54 years: 27 were Spanish and the other 27 were Moroccans residing in Spain. The groups were selected to ensure that clear cultural differences existed between them: they spoke different languages (Spanish versus Arabic), professed different religions (Christians versus Muslims), had different traditions, and came from very different geographical contexts (Europe versus Africa).

During the study, both groups underwent different tests of intellectual capacity: for example, a test of non-verbal intelligence, and various neuropsychological tests that measure functions such as visual memory and executive functions.

Despite the two groups being similar in terms of sex, educational level and socio-economic status, the results showed that in the test of non-verbal intelligence, the Spanish group obtained a higher IQ score than the Moroccan group. Moreover, the neuropsychological skills used in each subtest were clearly dependent on the country of origin of each participant. In other words, the same test can measure different cognitive functions in individuals from different cultures.

In the light of the results of this study, the authors suggest that the non-verbal tests cannot be considered culture-free and confirm the importance of validating the tests in their cultural context.