Green tea is known to contain antioxidants and nutrients that many believe enhance health and lower the risk of cancer. New research now finds that green tea may enhance cognitive functions — especially a person’s working memory.
The Swiss findings could have clinical implications down the road for treating cognitive impairments in psychiatric disorders such as dementia.
Findings from the new research are published in the journal Psychopharmacology.
The main ingredients of green tea have been thoroughly studied in cancer research. Recently, scientists have also been inquiring into the beverage’s positive impact on the human brain.
Different studies were able to link green tea to beneficial effects on cognitive performance.
However, the neural mechanisms underlying this cognitive enhancing effect of green tea remained unknown.
In the new study, European researchers found that green tea extract increases the brain’s effective connectivity, meaning the causal influence that one brain area exerts over another.
“Our findings suggest that green tea might increase the short-term synaptic plasticity of the brain,” said researcher Stefan Borgwardt, M.D., Ph.D.
This effect on connectivity also led to improvement in actual cognitive performance: Subjects tested significantly better for working memory tasks after being administered green tea extract.
For the study, healthy male volunteers received a soft drink containing several grams of green tea extract before they solved working memory tasks. The scientists then analyzed how this affected the brain activity of the men, using magnetic resonance imaging (MRI).
The MRI showed increased connectivity between the parietal and the frontal cortex of the brain. These neuronal findings correlated positively with improvement in task performance of the participants.
The research results suggest promising clinical implications.
For example, modeling effective connectivity among frontal and parietal brain regions during working memory processing might help to assess the efficacy of green tea for the treatment of cognitive impairments in neuropsychiatric disorders such as dementia.
Source: University of Basel