The impact of blackcurrant juice on attention, mood and brain wave spectral activity in young healthy volunteers

Abstract

There is a growing body of evidence from randomized controlled trials which indicates that consumption of berries has a positive effect upon the cognitive function of healthy adults. It has been recommended that studies combining cognitive and physiological measures be undertaken in order to strengthen the evidence base for the putative effects of flavonoid consumption on cognitive outcomes. This pilot study utilized a randomized, double-blind and placebo controlled crossover design to assess the influence of the acute administration of anthocyanin-rich blackcurrant juice, standardized at 500 mg of polyphenols, on mood and attention. Additionally, this trial used electroencephalography (EEG) to assess if any changes in cognitive performance are associated with changes in localized prefrontal cortex neuronal activity in nine healthy young adults. Outcomes from the pilot EEG data highlight an anxiolytic effect of the consumption of a single serve blackcurrant juice, as indexed by a suppression of α spectral power, and an increase in the slow wave δ and θ spectral powers. There was also an indication of greater alertness and lower fatigue, as indexed by an increase in β power and suppression of α spectral power. Outcomes from the CogTrack™ system indicated a small acute increase in reaction times during the digit vigilance task.

Keywords:

• Blackcurrants
• Attention
• Computerized cognitive testing
• CogTrack
• EEG

Acknowledgements

Anthony Watson, Edward Okello, Helen Brooker, Keith Wesnes & Sophie Lester contributed to the design of the project, interpretation of results and preparation of this manuscript. Gordon McDougall wrote the methods for and conducted LC/MS analysis of the blackcurrant drinks. The authors wish to acknowledge the School of Agriculture, Food and Rural Development, Newcastle University for the use of the NU-Food Research Facility and the James Hutton institute for the time and costs associated with LC/MS analysis. Authors would also like to acknowledge Wesnes Cognition Ltd for the free use of the CogTrack system which is proprietary to Wesnes Cognition Ltd (www.wesnes.com).

Disclaimer statement

Contributor None.

Funding None.

Conflicts of interest None.

Ethics approval Ethical approval was granted by the Faculty of Science, Agriculture and Engineering Ethics committee, Newcastle University. October 2015.

ORCID

A. W. Watson http://orcid.org/0000-0001-6124-9182

H. J. Brooker http://orcid.org/0000-0002-7908-263X

G. J. McDougall http://orcid.org/0000-0002-2285-0124

K. A. Wesnes http://orcid.org/0000-0002-4498-8511