fMRI technology brain blood flow, 02 consumption and dive time

[cdavis]

Divers have noticed that calming the mind increases breath hold time. I'd always thought this was primarily because of lower muscular tension lowering c02 production, but turns out that the brain itself(a major 02 burner) is largely responsible.The brain can increase or decease blood flow to areas of the brain that are working. That is what fMRI technology measures and clearly shows. Presumably those areas are burning more 02. Calm the mind and the brain burns less 02 and produces less c02 in the core where it has the most effect on desire to breath.

Very cool.

I'd love to see a fMRI study that would shed light on how much calming produces how much less co2

 

[Kars]

Great info, great question!

btw I always inform my students how much O2 a brain can use, just let them think of something really nice... , as opposed to just passively observing, and notice the difference. The positive nice thought cost much more O2 then the passive observing mindset.

 

[Ronnie]

I used to work with critically head injured kids. We'd totally anaesthetise them partly to dampen the metabolic demands of the brain. Same basic principle.

Zazen type meditation might be useful? Something I need to get into. I wouldn't be surprised if quite a lot of members of this board practised meditation in some form or another.

 

[Apneaddict]

My best holds and easiest holds (one in the same) are ones where my mind is empty for the majority of it - almost in a trance like state or super relaxed and asleep.

The holds where I'm aware and conscious of every second that passes are ones where I'm contracting like mad and doubt that they have ever gotten over 4:30 like this and they are a LOT of work!

 

[cdavis]

Ditto to Apneaaddict.

I don't get to a "meditative", almost asleep state very often, but when I do, I know a long dive is coming next. Did not realize how much of that was less brain c02 production.

Connor

 

[Kars]

Same here!