On January 4, PJ Eby sent around an email linking an... interesting... website. The claim on the particular webpage he linked was as follows:
the normal span of your breath is critical to how well your mental faculties can function
the best activity for increasing your breath span is held-breath underwater swimming
this also results in an increase in intelligence caused by a permanent increase in blood flow to the brain
being fully underwater is important to the practice because it induces the diving reflex response
This site is part of a sales pitch, so many of the claims are stated in hyperbolic language. I've already noted one factual error: the webpage claims that being underwater triggers the diving reflex, while in fact (or at least, according to Wikipedia) the diving reflex is triggered when one's face is immersed in water colder that 21 °C.
But there is a testable claim here: learn to hold your breath for longer periods of time -- particularly in conditions that elicit the diving reflex -- and you will see increased intelligence. I know that some readers of LW regularly train and test their intelligence, so I offer this as an easily implemented potential method. The possible gains seem to me to outweigh the costs of the training and the low prior probability of the claim.
Reading the part about breathing reducing attention during reading caused me to pay attention to my breathing while reading which reduced my attention, suggesting that breathing during reading reduces attention. Very clever, Mr. Wenger! As JoshuaZ points out, breathing seems unnoticed when one isn't actively thinking about it.
One also has to take into account the probability that this training has negative consequences, which, knowing the effects of hypoxia on neurons, is not negligible.
On January 4, PJ Eby sent around an email linking an... interesting... website. The claim on the particular webpage he linked was as follows:
This site is part of a sales pitch, so many of the claims are stated in hyperbolic language. I've already noted one factual error: the webpage claims that being underwater triggers the diving reflex, while in fact (or at least, according to Wikipedia) the diving reflex is triggered when one's face is immersed in water colder that 21 °C.
But there is a testable claim here: learn to hold your breath for longer periods of time -- particularly in conditions that elicit the diving reflex -- and you will see increased intelligence. I know that some readers of LW regularly train and test their intelligence, so I offer this as an easily implemented potential method. The possible gains seem to me to outweigh the costs of the training and the low prior probability of the claim.