Centre for Occupational and Health Psychology, School of Psychology, Cardiff University, UK
J Psychopharmacol. 2013 Jan;27(1):71-6. doi: 10.1177/0269881112460111. Epub 2012 Sep 26.
Research has shown that extraverts performing a working memory task benefit more from caffeine than do introverts. The present study aimed to replicate this and extend our knowledge by using a lower dose of caffeine (65 mg) and a range of tasks related to different components of working memory. In addition, tasks assessing psychomotor speed and the encoding of new information were included to determine whether caffeine-extraversion interactions were restricted to working memory tasks. A double-blind design was used, with 128 participants being randomly assigned to caffeinated or de-caffeinated coffee conditions. The results showed that caffeine interacted with extraversion in the predicted direction for serial recall and running memory tasks. Caffeine improved simple reaction time and the speed of encoding of new information, effects which were not modified by extraversion. These results suggest possible biological mechanisms underlying effects of caffeine on cognitive performance.
研究表明，在执行工作记忆任务时，外向者从咖啡因中获益多于内向者。本研究旨在通过使用较低剂量的咖啡因（65 毫克）和一系列与工作记忆不同成分相关的任务来复制这一结果，并扩展我们的知识。此外，还包括评估心理运动速度和新信息编码的任务，以确定咖啡因-外向性相互作用是否仅限于工作记忆任务。采用双盲设计，将 128 名参与者随机分配到含咖啡因或不含咖啡因的咖啡条件下。结果表明，咖啡因与外向性的相互作用在序列回忆和运行记忆任务中呈预期方向。咖啡因提高了简单反应时间和新信息的编码速度，而外向性并没有改变这些效应。这些结果表明，咖啡因对认知表现的影响可能存在生物学机制。
