Caffeine (4 mg/kg) influences sustained attention and delayed free recall but not memory predictions

Abstract

This experiment was conducted to examine the influence of a moderate dose of caffeine (4 mg/kg) on delayed memory, metamemory, and sustained attention. One hundred and forty-two volunteers ingested either caffeine or placebo during a study session which included three different memory tasks (free recall, cued recall, and recognition), and they made predictions of future memory performance. On day 2, participants again ingested either caffeine or placebo and completed memory tests. Sustained attention performance was measured on both days, and caffeine reliably improved hit rates and response latencies. A reliable drug-state interaction was detected only in the free recall test of memory. Caffeine did not affect the magnitude or accuracy of memory predictions, but there was some evidence that expectancies about caffeine were related to cognitive performance. Overall, caffeine's impact on memory and metamemory was not robust in this study. Copyright 2001 John Wiley & Sons, Ltd.

Effect of caffeine on prospective and retrospective duration judgements

“…Because the cognitive effects of caffeine can vary with time of day (Anderson and Revelle, 1994;Kelemen and Creeley, 2001), all testing was conducted at approximately the same time of day (the afternoon). Participants were also instructed to abstain from caffeine for 4 h prior to the experiment and to not eat or drink anything for 1 h before arriving.…”

Identifying experimental methods to determine the effect of pain on attention: a review of pain, caffeine, alcohol and nicotine studies

“…For example, the detection of a single digit is significantly impaired by increasing doses of alcohol (Rohrbaugh et al, 1988). Caffeine has also been found to increase the number of correct hits for both single and multiple digit versions of the task (Brice and Smith, 2001;Kelmen and Creeley, 2001). However, findings relating to caffeine-related improvements (speeding) in reaction time are less conclusive.…”

“…Caffeine Kelmen and Creeley (2001) 120 Between groups; Placebo versus caffeine (4 mg/kg) across two days (Caffeine-Caffeine, Caffeine-Placebo, PlaceboCaffeine, Placebo-Placebo).…”

The effect of black tea on human cognitive performance in a cognitive test battery

“…Trial making is a complex task that requires sustained attention, alertness, speeded motor activity to be activated at the same time. Previous studies showed a positive effect of caffeine on sustained attention [36] alertness [25] and motor activity [43] separately. Trail making test confirms our hypothesis that a merging of facilitation events might produce a combinatory effect on cognitive processing.…”

“…However, previous studies reported inconsistent results. These studies used different tasks [25,26], varied the dosage of caffeine and L-theanine in the tea [26][27][28], tested participants in different cognitive tasks [8,20,29,30]. Therefore, we aimed to identify the influence of BT consumption on human cognitive functioning, testing the participants in a wide range of cognitive tasks with a low dose that is 50 mg and 15 mg respectively.…”