Feeling lonely while in social isolation causes similar changes in the brain as hunger

CAMBRIDGE, Mass. — You may have heard of being “hangry,” a feeling of hunger brought by being angry or irritable. Now, researchers say they’ve discovered that feeling lonely while in social isolation can also cause similar changes in the brain that act like hunger.

Scientists from MIT say the brain craves company in the same way we yearn for a meal when we’re without food. Their findings shed fresh light on why social distancing is so hard. Millions have been deprived of seeing friends, family, and even co-workers as COVID-19 keeps entire nations shut down.

“People who are forced to be isolated crave social interactions similarly to the way a hungry person craves food. Our finding fits the intuitive idea that positive social interactions are a basic human need, and acute loneliness is an aversive state that motivates people to repair what is lacking, similar to hunger,” says study senior author Rebecca Saxe in a university release.

The study, published in the journal Nature Neuroscience, shows social distancing can have serious side effects, including drug addiction. Humans are a social species and interactions trigger the “feel good” chemical dopamine. This substance also floods into the brain’s grey matter when we eat.

Having a craving for company

In the first analysis of its kind, 40 volunteers underwent a series of trials lasting ten hours each. In one, participants sat alone in a room with no one to talk to and with no access to the internet or social media.

“There were a whole bunch of interventions we used to make sure that it would really feel strange and different and isolated,” Saxe explains. “They had to let us know when they were going to the bathroom so we could make sure it was empty. We delivered food to the door and then texted them when it was there so they could go get it. They really were not allowed to see people.”

In the other experiments, the group fasted or behaved normally. After each task, researchers scanned the volunteers’ brains using an MRI machine. The results reveal brains overreacted to pictures of social scenes when subjects were in isolation.

The same neurons lit up when the group also saw creamy, cheesy pasta or refreshing berries when they were hungry. Their cells began producing dopamine. The lonelier or hungrier the participant felt, the greater the response. Researchers say the size of the effect of isolation and fasting appear to be very similar.

“For people who reported that their lives were really full of satisfying social interactions, this intervention had a bigger effect on their brains and on their self-reports,” Saxe reports.

Hunger and loneliness may both impact brain development

Participants also self-reported increased social or food craving after isolation or fasting, respectively. The study notes that hunger can delay development on a cognitive, social, and emotional level. This includes reading, language, attention, memory, and problem-solving capabilities.

Children who experience hunger early on are more likely to perform poorly academically, repeat a grade or require special assistance.

“Chronic social isolation and loneliness are associated with lower physical and mental health but little is known about the consequences of acute mandatory isolation,” study authors write in their report.

Researcher conclude that positive social interactions may be a basic human need, just like food consumption or sleep. Extended periods of isolation, especially during development, can dramatically disrupt behavior and brain function.

SWNS writer Mark Waghorn contributed to this report.