Cognitive Speed and Subsequent Intellectual Development:

The hypothesis that a measure of intellectual speed assessed at one point in time would predict intellec-tual achievement at a later point in time was evaluated with a time-lagged cross-correlational analysis, an application of causal modeling techniques. Longitudinal data for 32 males and females, tested in 1944 (mean age 19.5 years) and in 1972 (mean age 46.7 years), supported the hypothesized relationships with an associated p <.01. The Relations Factor of the Army Alpha Examination — consisting of scores from a highly speeded simple analogies test and a short-term memory test — administered at age 20 was highly predictive of both verbal and numerical ability in middle age. The results highlight the cognitive intellec-tual aspect of the speed of behavior. In addition, these findings supplement Hunt's studies of the rela-tionships between speed of cognitive processing and psychometric abilities in young adults, and empha-size the importance of cognitive speed for subsequent intellectual development. Implications for the intellectual speed hypothesis of Birren and the utilization of time-lag designs in longitudinal research are discussed. I MPLICIT in the development of psycho-metric intelligence tests, as well as much cognitive processing research, is the desire to understand and predict the development o