Neural Effects of Green Tea Extract on Dorsolateral Prefrontal Cortex

Exploratory Behavior Clinical Trial

Status Completed

Clinical Trial Summary

Green tea is being recognized as a beverage with potential benefits for human health and on cognitive function. In vitro and in vivo studies provide preliminary evidence that green tea intake may play a positive role in improving effects on cognitive functions. The investigators aim to examine the neural effects of green tea extract on brain activation in humans.

Clinical Trial Description

As functional neuroimaging provides a means of examining how green tea extract acts on the brain, we used functional magnetic resonance imaging (fMRI) to study healthy volunteers while they performed a working memory task following intra-gastric administration of either 250 ml or 500 ml Rivella green® (RG), a milk whey based green tea extract containing soft drink, or Rivella blue® (RB), a milk whey based soft drink without green tea extract as sham condition in a double-blind, controlled design. Based on the literature on pharmacological and behavioural effects of green tea, we hypothesized - a priori - that green tea extract would subtly modulate the engagement of the dorsolateral prefrontal cortex (DLPFC), a brain region critically involved in many cognitive functions such as working memory processing.

A double-blind, controlled, within-subject study with counterbalanced order of substance administration using an established protocol (6-8) was conducted over 4 sessions (250 ml or 500 ml Rivella green® (including green tea extract; RG), 250 or 500 ml Rivella blue® (RB). Each participant was scanned four times with a one-week interval between scans. The order of substance administration across sessions was counterbalanced across subjects, such that equal numbers followed each substance sequence. ;

Study Design

Allocation: Randomized, Endpoint Classification: Pharmacodynamics Study, Intervention Model: Crossover Assignment, Masking: Double Blind (Subject, Investigator), Primary Purpose: Prevention

Related Conditions & MeSH terms

• Exploratory Behavior

• NCT number: NCT01615289
• Study type: Interventional
• Source: University Hospital, Basel, Switzerland
• Status: Completed
• Phase: N/A
• Start date: July 2010
• Completion date: January 2012