Dietary Caffeine, Performance and Mood: Enhancing and Restorative Effects after Controlling for Withdrawal Reversal

Vol. 52, No. 1, 2005

Free Abstract Article (References) Article (PDF 201 KB)

Original Paper

Dietary Caffeine, Performance and Mood: Enhancing and Restorative Effects after Controlling for Withdrawal Reversal
Jack E. James, M. Elizabeth Gregg, Marian Kane, Frances Harte

National University of Ireland, Galway, Ireland

Address of Corresponding Author

Neuropsychobiology 2005;52:1-10 (DOI: 10.1159/000086172)

Key Words

Caffeine
Performance
Mood
Sleep restriction
Withdrawal reversal

Abstract

This study aimed to determine whether sustained (i.e. dietary) use of caffeine has net effects on performance and mood compared with sustained abstinence, and whether dietary caffeine restores performance and mood adversely affected by sleep restriction. Participants (n = 96) alternated weekly between ingesting placebo and caffeine (1.75 mg/kg) three times daily for 4 consecutive weeks, while either rested or sleep restricted. Performance involved either a single task requiring sustained vigilance or a varied battery of brief psychomotor and cognitive tasks, and mood was assessed using the Profile of Mood States. Caffeine had no significant net enhancing effects for either performance or mood when participants were rested, and produced no net restorative effects when performance and mood were degraded by sleep restriction.

Author Contacts

Prof. Jack E. James
Department of Psychology
National University of Ireland, Galway
Galway (Ireland)
Tel. +353 91 512 016, Fax +353 91 521 355, E-Mail j.james@nuigalway.ie

Article Information

Published online: June 3, 2005
Number of Print Pages : 10
Number of Figures : 1, Number of Tables : 2, Number of References : 39

Medline Abstract (ID 15942257)

Download Citation

Cited In

This journal is part of the first subject package of the Karger

Journal Archive Collection

Information on packages (PDF)
Free sample issues

For non-native English speakers and international authors who would like assistance with their writing before submission, we suggest American Journal Experts for their scientific editing service.