I experienced this so many times in my career. I blamed myself, I cried, I yelled at the walls in my deep frustration. How can I possibly think for 20 minutes, calculate all kind of stuff and than play a move as if I don't care?! Probably you know the look of your coach/team captain, when you tried to explain yourself and to yourself what happened. No matter what you were trying to say, the conclusion might have been more or less the same one: lack of concentration or your restless personality.
A few days ago, one of my friends sent me a link with an article from The New York Times, which gives an interesting insight on the above topic. After many years of researches and experiments, psychologists brought into the light a new perspective on the biases (interference) from people's decisions.
In brief: every single day we are bombarded with all kind of decisions we have to make and the cumulative effect of these decisions is not an obvious one. Virtually, no one has a gut-level sense of just how tiring it is to decide. Big decisions, small decisions, they all add up. Choosing what to have for breakfast, where to go for a walk before the game, whom to speak with, how many things to buy from the supermarket — these all deplete willpower, and there's no obvious symptom of when that willpower is low.
No matter how rational and high-minded you try to be, you can't make decision after decision without paying a biological price. It's different from ordinary physical fatigue — you're not consciously aware of being tired — but you're low on mental energy. The more choices you make throughout the day, the harder each one becomes for your brain, and eventually it looks for shortcuts, usually in either of two very different ways. One shortcut is to become reckless: to act impulsively instead of expending the energy to first think through the consequences. (Sure, play that move! What could go wrong?) The other shortcut is the ultimate energy saver: do nothing. Instead of agonizing over decisions, avoid any choice. Unfortunately in chess, we have to make a move, we can't say "pass" or to take a break and walk around when it's our turn.
In fact, chess is, in its nature, a big decision making process with its almost infinite moves and the emphasis it places on thinking ahead. Of course you get tired at some point, without even realizing it! So many lines, so many branches in the tree, so many decisions while you calculate...even much more than the moves which are actually played on the board. If you add to this, all the other decisions you have to take throughout the day, one might discover that the life of a chess player is all about...choices!
Maybe the coaches will now be a bit more understanding when such an unfortunate thing will happen: a blunder. Of course, this shouldn't exempt you of any responsability:)
"Good decision making is not a trait of the person, in the sense that it’s always there," psychologists say. "It's a state that fluctuates".
And that's why Grandmasters are...Grandmasters. Especially the top ones, counsciously or subcounsciously, discovered the importance of regularity, structuring their lives so as to conserve energy. They have a certain rythm before the game, they establish habits that eliminate the mental effort of making choices. You shouldn't be surprised if you see the same GM walking at the same hour around the same place. Instead of counting on willpower to remain robust all day, they conserve it so that it will be available for the important game. And during the game, we can usually see on their boards a chocolate bar, coffee, Coke, something that contains sugar, to restore their glucose level. Most of the times it will be the same drink, the same candy, the same injection of indulgence...it might seem a bit boring, but in fact it's very smart: your brain can rest in peace.
"The best decision makers," psychologists say, "are the ones who know when not to trust themselves."