Neural Effects of Green Tea Extract on Dorsolateral Prefrontal Cortex
Study Details
Study Description
Brief 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.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
Detailed 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
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Active Comparator: Green tea extract, 250 ml Single intragastric instillation of 250 ml green tea extract |
Dietary Supplement: Single intragastric instillation of 250 ml green tea extract
Intragastric instillation by feeding tube
|
| Active Comparator: Green tea extract, 500 ml Intragastric instillation of 500 ml green tea extract solution |
Dietary Supplement: Single intragastric instillation of 500 ml green tea extract
Intragastric instillation by feeding tube
|
| Placebo Comparator: Control solution, 250 ml Intragastric instillation of 250 ml control solution |
Dietary Supplement: Single intragastric instillation of 250 ml control solution
Intragastric instillation by feeding tube
|
| Placebo Comparator: Control solution, 500 ml Single intragastric instillation of 500 ml control solution |
Dietary Supplement: Single intragastric instillation of 500 ml control solution
Intragastric instillation by feeding tube
|
Outcome Measures
Primary Outcome Measures
- Functional magnetic resonance imaging (fMRI) in healthy volunteers while they performed a working memory task [0 and 45 min]
Whole brain analysis with a cluster-level threshold was followed by an a priori defined region of interest analysis of the dorsolateral prefrontal cortex including a cluster-level threshold and family-wise error adjustment for multiple comparisons.
Eligibility Criteria
Criteria
Inclusion Criteria:
- right-handed healthy males, no drugs, non-smoking
Exclusion Criteria:
- drug abuse, smoker, left-handed
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | University Hospital | Basel | Switzerland | CH-4031 |
Sponsors and Collaborators
- University Hospital, Basel, Switzerland
Investigators
- Principal Investigator: Christoph Beglinger, MD, University Hospital, Basel, Switzerland
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- EKBB 32/09