Whether it's braving the long line at a trendy new restaurant or waiting a few extra minutes to see if there's a post-credits scene after a movie, the decision to persevere or drop it depends on specific parts of our brain.
Waiting isn't always about self-control. The decision to wait (or not to wait) also involves assessing the value of the potential reward. In an experiment examining wait times in people with lesions in the brain's frontal cortex, psychologist Joe Kable of the University of Pennsylvania and his research team found that subjects with damage to certain parts of the prefrontal cortex were less likely to finish things. to wait.
“[Our] findings suggest that regions of the frontal cortex make computationally distinct contributions to adaptive persistence,” he and his team said in a study recently published in the Journal of Neuroscience.
Wait for it
Kable looked for subjects with damage to three parts of the prefrontal cortex: the ventromedial prefrontal cortex, the dorsomedial prefrontal cortex and the anterior insula. Their behavior was compared with both healthy controls and controls with lesions in the other parts of the frontal cortex.
The ventromedial prefrontal cortex is involved in action control, memory and decision making. The dorsomedial prefrontal cortex is even more important when it comes to decision making; it also plays an integral role in regulating cognition, emotion and action. The anterior insula regulates how subjective feelings are processed. The performance of subjects with lesions in these areas was compared not only with healthy controls, but also with controls with lesions in other parts of the frontal cortex.
Participants seated in front of a computer screen were told that a coin would appear on the screen. That coin would increase in value over time and change color as its value matured. It can then be sold for a 10 cent reward by pressing the spacebar. Even if the coin was not yet mature, the space bar could still be pressed to stop the waiting period and make a new coin appear, even though they missed out on the 10 cents.
What no one who participated in this experiment knew was that the maturation of the coins followed one of two patterns. In the high persistence pattern, the coin could mature at any time over a 20 second period, so waiting was the best strategy. Conversely, in the limited persistence alternative, it was optimal to stop waiting after two seconds if the coin was not mature by then, because if it was not, the coin would not mature for the full 40 seconds. this test was to make as much money as possible in 12 minutes.
