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L-theanine: Learning and cognition

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With a chemical structure very similar to glutamine, L-theanine is an amino acid with a reputation for being a relaxing agent without causing sedation. 

Found mainly in green tea, multiple studies have shown L-theanine notably increases relaxation as assessed by neural measurements such as alpha waves. Animal neurochemistry studies suggest that L-theanine increases brain serotonin, dopamine and GABA levels and has affinities for several glutamate receptor subtypes. These properties may also go to explain how L-theanine exerts its neuroprotective effects. Behavioural studies in animals suggest improvement in learning and memory. 

Overall, L-theanine displays a neuropharmacology suggestive of a possible neuroprotective and cognitive enhancing agent. This certainly makes it a worthwhile consideration as a supplement for learning and memory. 

In this infographic we examine L-theanine as it relates to cognition, learning and focus. We also explore the areas of the brain and the specific neurotransmitters that L-theanine has been shown to influence. 


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Melissa Lee
Melissa is a designer turned nutritionist, who has combined the two modalities to create purposeful designs for various health publications and websites. Having initially studied Multimedia Systems Design, she then went on to complete a BHSc in Nutritional Medicine which led to her involvement in the integrative medicine industry and eventually to FX Medicine.