A study that has recently gone to press (Bilaut et al., in press) suggests that elite freediving may cause mild, but persistent short term memory loss. The study subjected elite freedivers (>6 min static breath hold), novice freedivers (>4 min static breath hold) and a control group to specific psychological tests.
The time to complete the tests was positively correlated with freediving static performance. In simple words this suggests that a better breath-hold means a slower brain.
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