Patience seems to be universally valued as a virtue. Find out how a new study sheds light on how our brains regulate our capacity to delay instant gratification.
My doctor ordered some routine blood work for me and, because of COVID, I arranged to have it done today in a less swamped lab in a smaller neighbouring town. When I arrived at the unfamiliar facility, the reception desk was empty.
I waited for a few minutes, and nobody arrived to serve me. I grew more and more impatient, and finally, I decided to poke my head into the door of the examining area. I was told that someone would be with me in just a moment.
My impatience didn’t accomplish anything. In a minute or two, someone cheerfully checked me in. Within about ten minutes, they had drawn my blood, I had provided my urine sample, and I was out the door and getting on with my day.
Writing This While on Hold with Revenue Canada
I’m writing this while I’m on hold with Revenue Canada. Because of COVID, they too are short-staffed. The wait time is going to be about an hour.
I could hang up and not get my question answered, I could sit on hold, fuming about the delay, or I could do something useful. That’s why I’ve decided to write this story about patience while I practice calmly waiting for a response.
Patience has been seen as a virtue since ancient times. The Book of Proverbs tells us that “”A patient man is better than a warrior, and he who rules his temper, than he who takes a city.”
“A Patient Man Is Better than a Warrior”
Scholars consider the Book of Job to be the ultimate exploration of patience in the face of adversity. In the New Testament, Paul tells his readers that “the fruit of the spirit is love, joy, peace, patience, kindness, goodness, faithfulness, gentleness and self-control. Against such things, there is no law.”
The Greco-Roman philosophers also prized long-suffering people. Socrates famously said, “He who seeks the truth must have infinite patience.”
Marcus Aurelius later said, “”God give me patience, to reconcile with what I am not able to change. Give me the strength to change what I can. And give me the wisdom to distinguish one from another.” Readers will recognize this as the source of what we now call the Prayer of Serenity.
“Three Things: Simplicity, Patience, Compassion.”
The Chinese founder of Taoism, Lao Tzu, told his disciples, “I have just three things to teach: simplicity, patience, compassion. These three are your greatest treasures.” We can see that cultures throughout the world considered patience to be a virtue.
Modern psychologists define patience as the capacity to suppress our impulse for instant gratification. Like the ancient philosophers, they consider patience to be essential to success in life.
Yet, scientists have never fully understood where patience comes from and how it works. Last week, a new study published in the journal Science Advances offered new insights into the age-old question.
Regions of the Brain that Promote Patience
A team of Japanese researchers from the Okinawa Institute of Science and Technology conducted a series of experiments on mice. They believe that they have pinpointed regions in the brain that promote patience using the familiar mood-regulating chemical serotonin.
Dr. Katsuhiko Miyazaki is a co-author of the study. He explained, “Our research shows that release of this chemical messenger also plays a crucial role in promoting patience, increasing the time that mice are willing to wait for a food reward.”
The mice used in the study were specially bred to have serotonin-releasing brain cells with a light-sensitive protein. This allowed the scientists to trigger these brain cells to release serotonin by shining a light on the mice.
Placed the Mice Inside a “Nose Poke”
The researchers then put the mice into situations where they could wait for a food reward. They placed the mice in a feeder called a “nose poke.” The scientists could give the mouse a food pellet to reward them for waiting.
In 75% of the trials, the mouse got a treat. Sometimes the wait time was six seconds, sometimes, it was ten, and sometimes it was random.
In the other 25% of the trials, the mouse didn’t receive a reward at all. The researchers noted how long the mice would wait with and without the light stimulating their serotonin levels.
Mice Waited Longer with Increased Serotonin Levels
When the investigators increased the serotonin levels, the mice were willing to wait longer to receive their treat. This worked best when the mice believed that the reward would come eventually but weren’t sure how long they’d have to wait.
As Professor Miyazaki put it, “For the serotonin to promote patience, the mice had to be confident that a reward would come but uncertain about when it would arrive.” The level of patience induced also depended on which part of the brain the researchers stimulated.
The investigators looked at a part of the brain called the dorsal raphe nucleus. They combined that area with one of three other brain regions, the nucleus accumbens, the orbitofrontal cortex, or the medial prefrontal cortex.
One Brain Area Played No Role in Regulating Patience
When the scientists stimulated the nucleus accumbens, they found no increase in waiting time. This implies that this area of the brain has no role in regulating patience with serotonin.
On the other hand, stimulating the orbitofrontal cortex or the medial prefrontal cortex caused the mice to wait longer, but not in precisely the same way. In the orbitofrontal cortex, serotonin’s release promoted patience as effectively as serotonin activation in the dorsal raphe nucleus.
The result was similar when reward timing was fixed, and when reward timing was uncertain. It was stronger with uncertainty. In the medial prefrontal cortex, the scientists only saw an increase in patience when the reward’s timing was varied, with no effect observed when the timing was fixed.
“Two Brain Areas Calculating Probability of Reward”
“This confirmed the idea that these two brain areas are calculating the probability of a reward independently from each other, and that these independent calculations are then combined to ultimately determine how long the mice will wait,” Professor Miyazaki explained. “This sort of complementary system allows animals to behave more flexibly to changing environments.”
Thanks for having the patience to finish this story. I hope your virtue was rewarded with at least a grain of truth that you found helpful. There’s a bonus.
Beyond patience, a better understanding of serotonin in the brain may lead to more effective treatments for the debilitating and potentially-fatal mental illness of depression. We’ll leave the final word to Professor Miyakazi.
More Effective Treatments for Depression
“This is an area we are keen to explore in the future by using depression models of mice. By pinning down these regions, this could open avenues to provide more targeted treatments that act on specific areas of the brain, rather than the whole brain.”
We always have more to learn if we dare to know.
Scientists reveal regions of the brain where serotonin promotes patience
Serotonergic projections to the orbitofrontal and medial prefrontal cortices differentially modulate waiting for future rewards
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It’s Hard (But Good for You) to Be Humble
Originally published at http://daretoknow.ca on December 9, 2020.