Experimental investigation of the effects of caffeine consumption on eyewitness memory

Many factors are researched for their potential impact on eyewitness memory (EM) and its reliability. Despite regular consumption of caffeine for its simulant effects, current knowledge on caffeine and memory is limited, particularly on EM. The aim of this experiment was to investigate the effects of caffeine on quality and accuracy of EM recall. It was hypothesised that increased levels of caffeine consumed would improve the accuracy and quality of EM and line-up identification (LI). An experiment was conducted with 97 participants, each of whom self-allocated into one of three beverage-consuming groups (k=3, no caffeine, some caffeine, high caffeine). Participants viewed a mock crime video following the consumption of caffeinated beverages and completed an EM recall questionnaire alongside a target-present LI. A one-way MANCOVA and Chi-Square test were conducted to test the hypotheses. Results indicated caffeine consumption did not significantly affect EM quality or accuracy. These contradicted findings of previous research. An unexpected confidence-accuracy effect did occur with the LI. Experimental strengths of this study were discussed. Practical implications indicated caffeine consumption does not affect EM accuracy or reliability; however, dosage limitations suggested need for future experimental research. The present study contributes to gaps in psychopharmacological research on forensic proceedings.