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Fatigue Is a Brain-Derived Emotion that Regulates to Ensure Protection (2012)

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Re: Fatigue Is a Brain-Derived Emotion that Regulates to Ensure Protection (2012)

#61

Post by lj3 »

saiya-jin wrote: post #42
lj3 wrote: post #31

Earlier quoted context omitted.

When I was 16, I was 130. That's after I spent three years in the weight room every day putting on muscle. I played every sport my school offered at least once, but I played football for 8 years. I never regretted it and I encourage everyone, especially the indoor geeky types, to try out for sports. Any sport. Even historical sword fighting. ;) It's an important experience that fewer kids are getting exposed to in th…

there are sports which will cripple your health in long run, almost guaranteed. many contact sports, it football comes to mind. some of my high school classmates are semi-cripples because of it (they can walk around, and that's about it). depression can be seen in their eyes - once you know what having a healthy and strong body means, and then losing it forever. I've done my share of team/contact sports in my youth.…

> there are sports which will cripple your health in long run, almost guaranteed. many contact sports, it football comes to mind.

Did you play football? The danger of permanent crippling injury has been blown way out of proportion by helicopter parents and the news. Of all the kids I played with and all the kids I coached (volunteer), only one of them ever wound up partially crippled. That kid in particular would routinely do daredevil stunts in his spare time. By the time he injured his knee, he was missing teeth, had blown his eyebrows off three times, and messed up that knee at least twice before stepping foot on the field.

Football is a safe sport, considerably safer than not playing. I hear on the news about concussions and crippling injuries, but I never see it in real life. Those things are pretty rare, especially when compared to vehicle accidents. I've seen far more lifetime permanent injuries come out of the soccer camp, to be honest.

Re: Fatigue Is a Brain-Derived Emotion that Regulates to Ensure Protection (2012)

#62

Post by gwern »

halayli wrote: post #21
gwern wrote: post #10

'Protection' might be the goal of physical fatigue, but it doesn't work for intellectual effort - what are you being 'protected from breaking' by not being able to write another line of code? Carpal tunnel? In that case, it looks more like it's about conserving energy or rotating to another task after having spent so much time on one task: "A Meta-Analysis of Blood Glucose Effects on Human Decision Making" http://www…

What about mental fatigue? The more you workout your brain the more it needs to rest. How would you like your brain to tell you that it needs to rest other than feeling fatigue? I find myself consistently productive over long spans without a burnout effect when I am sleeping at consistent hours, and working for consistent hours a day. When I overwork my productivity becomes inconsistent so I stopped doing that. I lea…

Why does your brain need to rest? What exactly 'builds up' and why don't regular tasks like the visual perception of the world cause this? And so on.

Re: Fatigue Is a Brain-Derived Emotion that Regulates to Ensure Protection (2012)

#63

Post by gwern »

dietrichepp wrote: post #13
gwern wrote: post #10

'Protection' might be the goal of physical fatigue, but it doesn't work for intellectual effort - what are you being 'protected from breaking' by not being able to write another line of code? Carpal tunnel? In that case, it looks more like it's about conserving energy or rotating to another task after having spent so much time on one task: "A Meta-Analysis of Blood Glucose Effects on Human Decision Making" http://www…

Perhaps from bad decisions? As I stay awake, the quality of my code drops pretty fast, social decisions get worse, I say the wrong thing to people, et cetera.

This is question-begging. 'We get fatigued because we get fatigued.'

Re: Fatigue Is a Brain-Derived Emotion that Regulates to Ensure Protection (2012)

#64

Post by gwern »

cel1ne wrote: post #35
gwern wrote: post #10

'Protection' might be the goal of physical fatigue, but it doesn't work for intellectual effort - what are you being 'protected from breaking' by not being able to write another line of code? Carpal tunnel? In that case, it looks more like it's about conserving energy or rotating to another task after having spent so much time on one task: "A Meta-Analysis of Blood Glucose Effects on Human Decision Making" http://www…

"The brain makes up 2% of a person's weight. Despite this, even at rest, the brain consumes 20% of the body's energy. The brain consumes energy at 10 times the rate of the rest of the body per gram of tissue. The average power consumption of a typical adult is 100 Watts and the brain consumes 20% of this making the power of the brain 20 W." http://hypertextbook.com/facts/2001/JacquelineLing.shtml

The resting metabolism is very high, because the brain is expensive to build and run. But it's not much more expensive to run on one task rather than another. This is one of the major flaws in the blood glucose theory of willpower as discussed by Kurzban: some additional sugar can't be 'gasoline' for the brain because the brain doesn't use up that much more energy working on something than not working on something. (As one might guess from the basal rate of 20%! Not much room left. Or from thermodynamics: when you walk or do physical exercise, you can feel your body heat up from how much energy you are burning. Your head doesn't heat up while doing arithmetic.)

Re: Fatigue Is a Brain-Derived Emotion that Regulates to Ensure Protection (2012)

#65

Post by oxryly1 »

This is an interesting method of building resiliency -- or anti-fragility -- into a complex system without adding complexity via a system of feedback for each component (or some other such cleverness).

(I.E.: Have an overarching "intense activity" timer or measuring device signal that the system is likely to suffer breakdown... just because it probably will.)

The key intelligence here comes from the fact that the human fatigue system evolved alongside the human organism, and thus has millions of years of results built in. As a result it's fairly accurate.

Re: Fatigue Is a Brain-Derived Emotion that Regulates to Ensure Protection (2012)

#66

Post by forgetsusername »

ArkyBeagle wrote: post #27
mrexroad wrote: post #25

My first thought was, "oh, reminds me of the SEAL's 40% rule... so if they're trained to ignore that limit, why don't they get hurt?" Then, in first google result [1], I read this: “I first met “SEAL” at a 100-mile run in San Diego and I was running this race as part of a six-person relay team with friends and he was running the entire race by himself,” Itzler said. “Who is this guy? I’ve never seen anything like it.…

Where does this come from in the larger culture? I can see why people who are soldiers or ... athletes at the varsity or pro level might be interested in it but why would anyone want to basically injure themselves as a ... hobby? I've worked with runners who had serious injury, soccer players who came in with bruises that you'd associate with a severe beating... I'm thinking "geez, it's gonna suck when you're 62." Be…

>but why would anyone want to basically injure themselves as a ... hobby?

Some people enjoy testing personal limits, physical and mental.

Re: Fatigue Is a Brain-Derived Emotion that Regulates to Ensure Protection (2012)

#67

Post by Noseshine »

digi_owl wrote: post #57
Noseshine wrote: post #49

Earlier quoted context omitted.

Having taken neuroscience courses for interest in the subject, the holes in our knowledge far exceed the knowledge - even if the introductory book is over a thousand pages (but that's how it is in most fields these days, and yet you only learn basics). For example, only very recently we found that the brain literally cleans itself (by flushing) during sleep ( http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3880190/ ). Yo…

Brings to mind the claim that we have X hours of focused mental effort we can spend each day. Go beyond that and we start dropping back to fight or flight instincts etc.

However, I don't think that is actually a real theory in neuroscience, it's more a made-up everyday rule. I doubt it is valid, except in the most general kind of way.

Re: Fatigue Is a Brain-Derived Emotion that Regulates to Ensure Protection (2012)

#68

Post by forgetsusername »

saiya-jin wrote: post #42
lj3 wrote: post #31

Earlier quoted context omitted.

When I was 16, I was 130. That's after I spent three years in the weight room every day putting on muscle. I played every sport my school offered at least once, but I played football for 8 years. I never regretted it and I encourage everyone, especially the indoor geeky types, to try out for sports. Any sport. Even historical sword fighting. ;) It's an important experience that fewer kids are getting exposed to in th…

there are sports which will cripple your health in long run, almost guaranteed. many contact sports, it football comes to mind. some of my high school classmates are semi-cripples because of it (they can walk around, and that's about it). depression can be seen in their eyes - once you know what having a healthy and strong body means, and then losing it forever. I've done my share of team/contact sports in my youth.…

>there are sports which will cripple your health in long run, almost guaranteed.

So will sitting on your chair in front of a computer 8 hours a day. Everything in moderation.

Re: Fatigue Is a Brain-Derived Emotion that Regulates to Ensure Protection (2012)

#69

Post by coredog64 »

uola wrote: post #54
mathattack wrote: post #28

Earlier quoted context omitted.

Interesting. I've trained with many Seals - they have ungodly cardio. I've never seen any that big, as the extra muscle kills their cardio.

Something seems fishy about that story. Not only are special forces people usually smaller, but getting hurt is a big no no. It will stop your training and severely jeopardize any mission you're on. Most special forces teaches the opposite of "if it's not hard we don't do it" i.e. to use your tactical advantage. That said, getting in to US special forces probably isn't that selective these days with having had to fil…

Anyone in any branch would be subject to charges for negligently incurring injury. I've heard a story about some guys in the Air Force who were written up for getting terrible sunburn while boating.

Re: Fatigue Is a Brain-Derived Emotion that Regulates to Ensure Protection (2012)

#70

Post by natdempk »

uola wrote: post #54
mathattack wrote: post #28

Earlier quoted context omitted.

Interesting. I've trained with many Seals - they have ungodly cardio. I've never seen any that big, as the extra muscle kills their cardio.

Something seems fishy about that story. Not only are special forces people usually smaller, but getting hurt is a big no no. It will stop your training and severely jeopardize any mission you're on. Most special forces teaches the opposite of "if it's not hard we don't do it" i.e. to use your tactical advantage. That said, getting in to US special forces probably isn't that selective these days with having had to fil…

The story wasn't told well in that post, but it is legit. I've heard him speak in person before. The way he tells it, he had three years of non-deployable time so it was the quickest way for him to accomplish his goal of getting into the Badwater ultramarathon to raise money for charity. Not ideal, but he knew that he would have time to fully recover from it.
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