Here Paul Black comments on the paper by Clark in this issue. Black first comments that the Clark paper highlights two possible factors that might effect trends of change over time. The first is that the population has become more adept at dealing with the types of challenges IQ tests present to them. Such explanations must be analyzed in light of…

Clark, Lawlor-Savage, and Goghari (this issue) point out that evidence of IQ rises had been documented decades before it was named the Flynn effect. These previous studies, however, were conducted sporadically and in isolated samples. Flynn (1984, 1987) examined them in a large-scale manner and was able to show their systematic and global nature.…

Average intelligence quotient (IQ) scores have been rising throughout the 20th century and likely before--a pattern now known as the Flynn effect. The central thesis of this paper is that the Flynn effect does not represent genuine increases in general intelligence but rather an increasing aptitude for the types of modern thinking that modern life…

Patterns of maintenance of ability across the life span have been documented on tests of knowledge ("Gc"), as have patterns of steady decline on measures of reasoning ("Gf/Gv"), working memory ("Gsm"), and speed ("Gs"). Whether these patterns occur at the same rate for adults from different educational…

Research on secular trends in mean intelligence test scores shows smaller gains in vocabulary skills than in nonverbal reasoning. One possible explanation is that vocabulary test items become outdated faster compared to nonverbal tasks. The history of the usage frequency of the words on five popular vocabulary tests, the GSS Wordsum, Wechsler…

Many Flynn effect (FE) studies compare scores across different editions of Wechsler's IQ tests. When construct changes are introduced by the test developers in the new edition, however, the presumed generational effects are difficult to untangle from changes due to test content. To remove this confound, we use the same edition of Wechsler…

In 1977 Draw-a-Person test was administered to fifth grade school children in a city and its surrounding rural villages in Turkey. In 2010, more than thirty years later, the test was administered again to a corresponding group of fifth grade children in the same locations. It is rare that we get scores from the "same" population over a…

The "Flynn effect" is a surprising finding, identified by James R. Flynn, that IQ test scores have significantly increased from one generation to the next over the past century. Flynn now brings us an exciting new book which aims to make sense of this rise in IQ scores and considers what this tells us about our intelligence, our minds…