The present study evaluated the effect of caffeine (225 mg) on cognitive performance in young, middle‐aged, and old subjects in a placebo‐controlled parallel groups design (n=60). Groups were matched for level of education and sex. Positive effects of caffeine, as compared to placebo, were found in middle‐aged subjects in the first trial of the word learning test. In contrast, caffeine had negative effects on the speed of searching short‐term memory in young subjects. Caffeine had no effect on the intercept, which is an indicator for sensorimotor speed, of a memory scanning task. The middle‐aged subjects appeared to regularly consume twice as much caffeine as the young and old subjects. These results were similar to earlier findings in a large population study. Although statistical analyses with habitual caffeine consumption as a covariate did not yield different results, a caffeine withdrawal effect was hypothesized to be responsible for the reduced cognitive performance of middle‐aged subjects receiving placebo. The habitual use of large amounts of caffeine by middle‐aged subjects may be a means to overcome the age‐related decrease in cognitive functioning that is caused by changes in information processing.
|Number of pages||8|
|Publication status||Published - 1 Jan 1998|