Is there any evidence of historical slowing of reaction time? No, unless we compare apples and oranges

In this paper, we reconsider a tendency of historical slowing of simple reactions to visual stimuli declared by Woodley et al. (in press). We begin by reconstructing a pendulum similar to that used by Galton and question whether such an instrument could indeed be appropriate for purposes of RT measurement. Next, we screened the other studies used in Woodley's meta-analysis and note the important properties of these studies that make the RTs that they report incomparable to each other. We claim that there is no evidence of the trend of historical increase in RT after these differences between studies are taken into account. Overall, we conclude that any cross-study comparison of RTs is uninformative and cannot provide any evidence for speculating on the topic of historical change in intelligence. © 2013 Elsevier Inc.