Why is thinking or using our muscles hard?

One question with two prongs. Why does doing things feel “hard” or difficult to us?

  1. Why is thinking difficult? If thinking is nothing more than electrical signals buzzing around in the brain and chemical reactions. Why does it seem so “hard?” My father used to make us play the math game where he would start with a number, say, 35 and then make us multiply it by a number, then subtract by another number, divide, add, etc. It is great for mental arithmetic skills, but this game is downright draining and I begged for relief after only a minute or so. Anyone knows people will do just about anything NOT to think, even if it is their best interest, because thinking is difficult!

  2. Why is using our muscles hard? From my simplistic understanding, muscles are composed of thousands (millions) of little muscle fibers and cells which physical change shape when undergoing certain chemical reactions. This allows them to pull. If the muscles have the required fuel to complete the “pull,” and the pull is below the threshold of the muscles ability, why does muscular work feel “hard” to us? It ought to feel no more difficult to us than a standard mechanical device feels about performing a duty (a cog in a gear box).

Chemical reactions are not “hard.” They just happen. Why do they seem difficult for us to perform?

It seems our brain and muscles are setup at some level to provide resistance to their own purpose.

  1. I’m not sure I agree. Lots of people enjoying thinking for the sake of it, and don’t find it “hard” or unpleasant. I prefer to be mulling something over in my head rather than leaving it sitting idle.

  2. WAG: It is in the body’s interests to conserve fuel in case we really need it. Presumably this is evolution’s way of reminding us not to use it up unnecessarily. Plus, even using muscles at well below capacity does cause fatigue, as meatbolites such as lactic acid are produced.

  1. Thinking is not “hard” per se but some people find it boring. Much easier to relax and not expend cognitive effort. You are thinking all the time when you are awake. Thinking you want a doughnut, thinking that girl is cute, thinking about taking a shower, thinking about that girls some more and so on. Ordering your thoughts to go through a math problem is more difficult as it is a task with a series of steps and you need to keep a bunch of things in mind at once (add two numbers, remember result, divide [break the problem into simpler steps, solve each one, combine results then recall previous answer and combine that, etc.]).

  2. Using muscles expends energy. Muscles release toxins when they are used which result in fatigue as your body endeavors to clear them out.

I don’t know if I can agree with that. It feels downright hard to me.

Maybe this delvs into the definition of thinking, but I frequently think about nothing. I can just stare at a wall and receive visual input. No gears a turnin’.

Maybe you’re out of practice. :slight_smile:

Seriously - I know plenty of people who wouldn’t find number exercises like those in the OP difficult at all, because they do them all the time. I’d really have to fire up my brain, because I rarely have to do math in my head that’s more difficult than “how much is 20% of this check?” On the other hand, I watch a lot of movies with subtitles and therefore am in practice, so I really don’t get it when people say they’re distracting - it’s practice. So is reading in general, and puzzle logic, and a lot of other things.

At this time of the year, I’m doing tax returns just about 'round the clock. I take my breaks over here because I like to keep thinking but I just have to stop thinking about taxes and give my mind a break on something else for a bit. So thinking is definitely effort, whether we find it enjoyable, boring or otherwise. (The same thing is true of sports, if you think about it).

The brain uses approximately 20% of the body’s calories doing all of this thinking. So it’s energetically expensive in a very tangible sense. I imagine that doing a lot of thinking really does tax the brain at the chemical level - it has to keep producing and breaking down neurotransmitters, dealing with waste products, etc. These are the same kinds of things muscles have to do when they’re working.

But when it comes to defining what “feels hard” I think we’re really talking perception not so much tangible effort. If you don’t like something, it feels more difficult.

Well, “hard” is also just electrical signals and chemical reactions…

Slothfulness is a valid evolutionary strategy, that’s my excuse. It conserves energy. For example, look at the, well, Sloth.

Thinking also burns calories, and eventually leads to fatigue. Lets go shopping.

I find math much harder now that my memory is not as good as it used to be. Plus, since it takes time, and my anxiety disorder makes me quite impatient. Plus, it can hurt. I actually understand those guys on TV who talk about their heads hurting after thinking.

Our minds and muscles have limits to their strengths.
We define hard as anything in the neighborhood of those limits.

here’s another perspective that thinking is hard.

i have MS. when my MS fatigue is at its worst, thinking is very exhausting. i have word problems, as in sometimes I can’t think of the word I want. if i struggle to figure out the right word, it is very tiring, and I can put myself in the bed for the rest of the day if I try too hard. it is the same kind of profound exhaustion of all availible, uh…

see here’s an example…

all my, not energy but what energy comes from like in the world, oil and coal and…


phew. gotta rest now. see how that works?

I find these to be excellent questions, particularly the ‘thinking’ question.

As with many things (running, doing chores, refraining from eating) accomplishing your desires (finishing a run, cleaning the kitchen, keeping your weight down) is met with mental resistence. These things may not be especially demanding, but it requires a force of will.

I think the difficulty that often comes with serious cognitive work rests with another part of the brain. The part that wants us to do something else. Some people find soduko fun and will seek to do them, but will find determining what shirt goes with what pants mentally exhausting and will just give up.

I think the feeling that heavy thinking is ‘hard work’ is almost entirely mental. While there may be some legitimate phyiscal toll taken when hard thinking is done, it must be de minimus.

But, to undermine most of the above, I wonder what happens to these artists and great thinkers (Picasso, Nash) who (apparently) drive themselves mad by delving deep into their minds. Is there something to be said for ‘working your brain too hard’?

“Hard” thoughts are those that go against the grain of what our brains evolved to do, i.e. survive in small bands of hunter-gatherers on the African plains.

So we routinely perform all sorts of very complicated computations effortlessly – facial recognition, physical simulation, social cost-benefit analysis. So effortlessly, in fact, that the hard work that our brain is doing is almost invisible to us. We only notice the effort of thinking when we try to apply our social-ape brains to problems they’re not particularly well-suited for.

I, too, have experienced the feelings expressed in the OP. My experiences have occurred in times when I was learning large amounts of data or difficult concepts. The difficulties in doing even ordinary things during those times were akin to times when I was experiencing depression, though without the negative feelings associated with depression.

I wish I could do that. I don’t think I ever find myself without an internal dialogue of some sort going on.

I suspect that a lot of people tense up facial/cranial muscle without realizing it when they are chewing on an idea, and this may lead to some of the physical sensation of strain.