A comparison of the effects of transcranial direct current stimulation and caffeine on vigilance and cognitive performance during extended wakefulness.

Abstract

BACKGROUND:

Sleep deprivation from extended duty hours is a common complaint for many occupations. Caffeine is one of the most common countermeasures used to combat fatigue. However, the benefits of caffeine decline over time and with chronic use.

OBJECTIVE:

Our objective was to evaluate the efficacy of anodal transcranial direct current stimulation (tDCS) applied to the pre-frontal cortex at 2 mA for 30 min to remediate the effects of sleep deprivation and to compare the behavioral effects of tDCS with those of caffeine.

METHODS:

Three groups of 10 participants each received either active tDCS with placebo gum, caffeine gum with sham tDCS, or sham tDCS with placebo gum during 30 h of extended wakefulness.

RESULTS:

Our results show that tDCS prevented a decrement in vigilance and led to better subjective ratings for fatigue, drowsiness, energy, and composite mood compared to caffeine and control in sleep-deprived individuals. Both the tDCS and caffeine produced similar improvements in latencies on a short-term memory task and faster reaction times in a psychomotor task when compared to the placebo group. Interestingly, changes in accuracy for the tDCS group were not correlated to changes in mood; whereas, there was a relationship for the caffeine and sham groups.

CONCLUSION:

Our data suggest that tDCS could be a useful fatigue countermeasure and may be more beneficial than caffeine since boosts in performance and mood last several hours.

• Authors: Lindsey K McIntire, R Andy McKinley, Chuck Goodyear, Justin Nelson
• Journal: Brain stimulation (Brain Stimul) 2014 Jul-Aug Vol. 7 Issue 4 Pg. 499-507 ISSN: 1876-4754 [Electronic] United States
• PMID: 25047826 (Publication Type: Comparative Study, Journal Article, Randomized Controlled Trial)
• Copyright: Published by Elsevier Inc.

Chemical References

• Caffeine

Topics

• Adult
• Affect (drug effects, physiology)
• Attention (drug effects, physiology)
• Caffeine (pharmacology)
• Cognition (drug effects, physiology)
• Fatigue (physiopathology, psychology, therapy)
• Female
• Humans
• Male
• Memory, Short-Term (drug effects, physiology)
• Psychomotor Performance (drug effects)
• Reaction Time (drug effects, physiology)
• Sleep Deprivation (physiopathology, psychology, therapy)
• Sleep Stages (drug effects)
• Surveys and Questionnaires
• Time Factors
• Transcranial Direct Current Stimulation
• Wakefulness (drug effects, physiology)