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Psychopharmacology

, Volume 225, Issue 2, pp 251–274 | Cite as

Caffeine as an attention enhancer: reviewing existing assumptions

  • Suzanne J. L. EinötherEmail author
  • Timo Giesbrecht
Review

Abstract

Rationale

Despite the large number of studies on the behavioural effects of caffeine, an unequivocal conclusion had not been reached. In this review, we seek to disentangle a number of questions.

Objective

Whereas there is a general consensus that caffeine can improve performance on simple tasks, it is not clear whether complex tasks are also affected, or if caffeine affects performance of the three attention networks (alerting, orienting and executive control). Other questions being raised in this review are whether effects are more pronounced for higher levels of caffeine, are influenced by habitual caffeine use and whether there effects are due to withdrawal reversal.

Method

Literature review of double-blind placebo controlled studies that assessed acute effects of caffeine on attention tasks in healthy adult volunteers.

Results

Caffeine improves performance on simple and complex attention tasks, and affects the alerting, and executive control networks. Furthermore, there is inconclusive evidence on dose-related performance effects of caffeine, or the influence of habitual caffeine consumption on the performance effects of caffeine. Finally, caffeine’s effects cannot be attributed to withdrawal reversal.

Conclusions

Evidence shows that caffeine has clear beneficial effects on attention, and that the effects are even more widespread than previously assumed.

Keywords

Caffeine Attention Simple attention Complex attention Attention networks Habitual caffeine consumption Withdrawal 

Notes

Acknowledgement

The authors are employees of Unilever, which markets tea and tea-based beverages.

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© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.Sensation, Perception and BehaviourUnilever R&D VlaardingenVlaardingenThe Netherlands

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