In a recent study, four groups of participants were told to commit to memory a list of 72 words. Two groups clenched one fist before memorizing and again before remembering the words. The other two groups switched the hand they clenched. The group that made a right-handed fist when memorizing the words and a left-handed fist when recalling them outperformed the other three. The study authors think that making a fist activates brain regions that are associated with memory.
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