Why are games like Sudoku so mentally satisfying? Do they activate a pleasure center in the brain, or do they merely provide the satisfaction of solving problems?
—Kirk McElhearn, Guillestre, France
Mark A. W. Andrews, professor of physiology and director of the Independent Study Pathway at the Lake Erie College of Osteopathic Medicine, explains:
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THOUGHT-STIMULATING activities such as Sudoku and crossword puzzles elicit positive emotional reactions from many (if not most) people. Science has not yet found a definitive answer as to why we enjoy these games so much, but research into emotions, though in an early state, has yielded some clues.
In your question you hint at a distinction between pleasure and satisfaction. In fact, MRI brain scans have provided evidence that there is indeed a significant difference between these feelings. Pleasure and happiness are passive emotions that happen to us as the result of outside stimuli. Satisfaction, on the other hand, involves an active pursuit—it is the emotional reward we get after adapting to a new situation or solving a novel problem. Studies have found that novelty is important in evoking satisfaction, which helps to explain why, even though all Sudoku puzzles are similar, solving each one of them instills a sense of accomplishment.
MRI scans indicate that a “satisfaction center” exists deep within the brain in a group of structures called the limbic system, which is best known as the seat of emotions and motivation. Specifically, satisfaction is most strongly associated with a structure called the striatum, which is activated by stimuli associated with reward. The striatum, in turn, is connected to areas of the frontal lobe that are involved with directing logical thoughts and actions toward goals. It is this interaction between the “intellectual” cortex and the “emotional” striatum that motivates us and gives us pleasure as a response to solving problems.
The chemical basis of satisfaction appears to be linked to the neurotransmitter dopamine, although it might also involve other neurochemicals. Dopamine plays many crucial roles in our mental and physical health and has long been known to be a factor in drug abuse and other addictive behaviors. In a way, people who say they are “addicted to crossword puzzles” are correct—the “rush” of accomplishment and satisfaction they get from solving each puzzle drives them to solve another.
Is it possible to think two thoughts simultaneously?
—Rich Dobrow, Barnegat, N.J.
Psychologist Barry L. Beyerstein of Simon Fraser University in Burnaby, British Columbia, replies:
THE ANSWER depends on how you define “thought.” If a thought is the perception or operation that you are currently aware of at any specific moment, it does seem that we can attend to only one mental process at once. Psychologists often describe this “selective attention” as functioning like a spotlight that roves about a stage, illuminating one (and only one) actor at a time. Yet if the definition of thought is broadened to include the many other mental operations going on in parallel with the one you happen to be attending to, it follows that we can be thinking more than one thought at a time.
If you have ever driven a car, you know that your brain can handle a wide variety of stimuli simultaneously. An accomplished driver does a huge amount of extremely vital processing outside of his or her awareness—taking in traffic signals, other cars and obstacles on the road while chatting to passengers, listening to the radio, watching the scenery or talking on the phone. The brain is responding to each and every stimulus appropriately, but attention can be focused on only one activity at a time. This small window of awareness we call “consciousness” highlights, for our voluntary supervision and response, only a small fraction of the many operations that are churning away simultaneously in our brain.
Neuroscientists see the brain as a collection of many specialized, semiautonomous modules that work in parallel. Each does its particular job unnoticed, behind the scenes. When a module completes a task, it moves to center stage for a short moment, grabs the so-called executive part of consciousness and displays the fruits of its unattended labors to our window of subjective awareness.
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