As a child, I loved going to the A&P store with my mother. We were newly arrived immigrants and still overwhelmed by the bounty of food available. Shopping for groceries seemed like a trip to Paradise. Unfortunately, Mother always had a list and would not deviate from it, although on occasion she would give in and buy me an "impulse purchase" - maybe a package of pound cake mix or a small package of strawberry Jell-O.
Current research on the relationship between decision making and will power would say that Mother was effectively "conserving" her will power and exhibiting fine "self-control." In fact, not until I read a recent article in the Sunday New York Times Magazine describing social neuroscience (the study of links between brain processes and social behavior) and "ego depletion" (essentially, mental fatigue generated by having had to make many decisions), I would not have thought that making decisions was a very taxing activity at all.
Now I know better. Making decision after decision zaps us mentally, whether it's seemingly as simple as deciding what to pack for a long trip to an unfamiliar place, making out a gift register for a wedding, or whether it's more complicated, like selling or buying a house or finding good assisted-living quarters for a family member.
Researchers say we do not realize we are low on mental energy; we do not feel "tired," but our brain looks for "shortcuts" anyway, and we end up not making the best decisions. For instance, we might think, "Why not tweet that provocative photo? Who's going to notice or really care, anyway?" Or, we may do nothing, taking the path of least resistance: "I won't answer that client's phone call today since I'm not certain how best to approach him on ____ anyway."
In some respects, this research simply verifies what we all already know. For instance, we know that if we're physically fatigued and driving long distances, we perk up with a can of soda pop, a candy bar, or coffee, or all three. Although we do not replenish our loss of mental energy or will power with coffee, something sweet (anything containing glucose - but NOT artificial sweetener) will do the trick and we'll be making better decisions, not get frustrated or lash out at others.
Believe it or not, this holds true even for dogs. If they're in training (to "sit" or "stay" or anything else, of course), they, too, eventually lose will power and have a tendency then to become "turf protective" and aggressive with other dogs. But offer them some glucose and they will recover their equanimity.
For someone who wants to diet, however, things are a little more complicated. In order not to eat, a dieter needs will power. But in order to have will power, a dieter needs to eat. Research has found that the mere expectation of having to exert self-control makes people hunger for sweets. (So, no wonder we have that joking stereotype about policemen eating doughnuts. We recognize that they need to exercise self-control all the time.) The key, as we might guess, lies in getting a steady supply of glucose all day long from eating other nutritious foods.
If you want to test the strength of your will power, do the following: When you are totally mentally fresh, immerse your hand in a bowl of ice water and hold it there for as long as you can. Count the seconds. Then, when you think you are mentally fatigued, immerse your hand again into a bowl of ice water and see how long you can keep it immersed. You should find that the time is much less than when you were mentally fresh.
• Ursula Carlson, Ph.D., is professor emerita at Western Nevada College.