There is no part of the human body as powerful as the mind. While the myth that humans only use 10% of their brainpower has been disproven for quite some time, it is true that there’s still a whole lot that modern science hasn’t figured out about the human mind.
Now, a fascinating new study conducted in Japan is shedding some light on the neurological processes and brain regions involved in our socially-motivated behaviors and desires.
The science behind it
On a subconscious level, humans’ desires can’t help but be influenced by other people. You may have had your eye on a particular coat or trendy brand for weeks, but if everyone and their brother is suddenly wearing that coat, you’re probably not going to be interested in buying it anymore. The same goes for experiences; let’s say you were planning a trip to Miami for six months and looking forward to it non-stop. Well, your sister decided to catch a spontaneous flight to South Beach last weekend and posted about it several times on Instagram. Suddenly your planned trip to Miami doesn’t feel nearly as unique or appealing.
So why are we so easily swayed by what others receive or do? The answer, like virtually everything else when it comes to human nature, lies in the mind. Researchers from the National Institutes of Natural Sciences have made an important first step in understanding socially-motivated desires in humans by looking to our closely-related evolutionary cousins: monkeys.
Human brains and monkey brains are, obviously, not the same. That being said, we share quite a few similarities brain-wise with our hairier primate ancestors.
Throughout their experiments, the research team was able to document that when a monkey knew other monkeys would receive the same reward, their reward just didn’t seem as appealing. These conclusions were drawn by focusing on the monkeys’ lip-licking behaviors. The more a monkey was anticipating a reward the more he or she licked their lips, and conversely, monkeys would lick their lips much less often if they weren’t all that interested in a reward.
Besides just confirming that monkeys’ desires are directly influenced by their peers just like humans, researchers were also able to identify the regions of the primates’ brains at play during these observations.
“We found a clear link between brain activity in the lateral hypothalamus and the licking behavior that represented the subjective value of the reward,” explains the first study author Atsushi Noritake.
The experiment explained
This was accomplished by monitoring the neural activity in the monkeys as each one was presented with a series of pictures that either indicated they would be receiving a reward themselves or that another monkey would get the prize. Some of the monkey’s brain cells activated, or “fired,” much more when they were presented with the chance of receiving a reward for themselves. Those same brain cells showed diminished activity when the monkey thought someone else would be receiving the gift.
A second experiment built upon these initial findings and confirmed that the same brain region (lateral hypothalamus) involved in getting excited about a reward or item also plays a role in the perception of social behaviors that influence how much a monkey values a reward.
Each monkey’s lateral hypothalamus was shut down using an inhibitory drug. While drugged, the monkeys’ lip-licking tendencies didn’t change at all when they thought they were just receiving a reward for themselves. But, after the hypothalamus had been disabled, the monkeys stopped appearing to care if any of their peers were going to be rewarded as well. Their lip-licking tendencies weren’t dependent at all anymore on whether or not another monkey received the same reward.
“Without a functioning lateral hypothalamus, it was as if the monkeys no longer processed what they were seeing as a social situation,” team leader Masaki Isoda concludes. “Thus, we believe that the lateral hypothalamus is necessary for shaping socially motivated behavior, perhaps in coordination with other brain areas such as the medial prefrontal cortex.”
These observations are, of course, limited to primates but they still represent a significant breakthrough in our understanding of the brain’s role in socially motivated desires and behaviors.
It appears that the tendency to become disinterested in an article of clothing as soon as everyone else starts wearing it, or move on from our favorite band after they start being played on the radio, is ingrained in our very evolutionary DNA. Better order those shoes you’ve been coveting before someone else does.
The full study can be found here, published in Proceedings of National Academy of Sciences.