A pair of new, highly realistic experiments have demonstrated that our ability to attend to social interactions changes as we get older, peaking in young adulthood and declining in older age as we look at other people's faces less often. 

For the study, published Thursday in Human Nature Behavior, researchers looked at social attentiveness among 268 participants who spanned three age groups: adolescents (10 to 19 years old), young adults (20 to 40 years old) and older adults (60 to 80 years old). In a groundbreaking experimental paradigm, the participants were tasked with navigating social interactions and bustling real-world environments while wearing eyeglasses that tracked what they were looking at, said Heather Ferguson, a professor of psychology at the University of Kent in the United Kingdom and the study's lead author. 

"The reason this was a really exciting project is because everything we had done — and everything anyone else had done to look at aging effects and social cognition — had been using very artificial, lab-based designs," she told The Academic Times. "This was the first time the questions had been taken out of the lab into fully immersive, unpredictable situations, and the first time we've actually looked what actually happens in real life — not just at people watching other people, or interacting with an avatar or a triangle or something on the screen, which is what often happens in these lab-based studies."

The study marks the culmination of a wide-ranging, five-year research project funded by the European Research Council that ended in February. The project aimed to show how our ability to engage in and draw information from social interactions changes as we age, with the researchers testing hundreds of people who ranged from 10 to 90 years of age. "I was really interested in how that change intersected with what we already know about cognitive decline," Ferguson said. "There's very steep cognitive development during adolescence and a really long, slow decline from about 40 years old that has been shown in older age. When we started this project, very little research had looked at the social domain." 

The team had previously found that the decline of certain cognitive and social skills starts in one's late 30s and early 40s — earlier than previously thought. The team's latest study adds to that picture, finding an age discrepancy in how participants navigated social interactions and physical spaces. In the first task, participants answered a series of questions designed to prompt them to talk about themselves. Then participants asked questions of the experimenter, an important role reversal because speaking is more cognitively demanding than listening. 

"When people are speaking, they tend to spend more time looking away from a person's face, looking at the background, whereas when you're listening, they spend much more time engaged and looking at the person's face," Ferguson said. "Moving attention away from a person's face while you're talking is really indicative that you're finding it difficult just to come up with a conversation, and you're managing that difficulty by attending away from the dynamic, complex information that is provided by the face." 

The researchers found that adolescents and older people performed similarly, spending less time looking at their conversation partner's face — suggesting that people are less able to meet the demands of social interactions during periods of cognitive development and decline. "If you want to be successful in your social interactions, you have to look like you're interested in what the person is saying and show all the right signals," Ferguson explained. "All of that is really effortful."  

In the second experiment, participants were given a map of University of Kent's campus and tasked with getting a leaflet from the college reception office and bringing it back to the lab. Regardless of their route, the participants were confronted with busy corridors full of things to look at. The experimenters monitored how often the participants looked at other people versus obstacles or their map, finding a somewhat surprising result along the way. 

"Overall, all our participants spent surprisingly little time looking at people; only about 5% of the time did they look at people in their environment," Ferguson said. "They were much more likely to look at objects and where they were going, the map — really, anywhere other than at people." That finding is a departure from lab-based studies that have shown that people tend to fixate on others in videos, when there is no risk that the other person will look back, she added.

As in the first experiment, the researchers found that adolescents and older adults paid less attention to people's faces as they walked around campus, providing further evidence that young adults are at the height of their social and cognitive abilities. But it's also possible that the results were influenced by the setting of the experiments, Ferguson said. 

"I would definitely say that your ability to engage and attend to social interactions peaks in young adulthood, but it is possible that there is also a social context effect here," Ferguson said. "The people that participants interacted with during their conversation and most of the people around in the university setting were young adults. There's a possibility that the young adults we tested were more likely to look at other people because they were like them — they were peers in terms of age — and the adolescents and older people were less likely because they were members of outgroups." 

Ferguson called for further research into how sociality and cognition are intertwined, which could help researchers and public health workers better understand loneliness as an accelerant of cognitive decline and raise awareness of the importance of staying socially engaged for older adults. 

"There is a circular relationship there, because aging comes with physical mobility issues, limiting your ability to go out and engage in social interactions," she said. "The less you do it, the less confident you feel about doing it. And when people feel this lack of confidence, they're less likely to engage — and there are all sorts of mental and physical repercussions when that happens."  

The study, "Tracking developmental differences in real-world social attention across adolescence, young adulthood and older adulthood," published May 13 in Human Nature Behavior, was authored by Martina De Lillo, Rebecca Foley, Matthew C. Fysh, Aimée Stimson and Heather J. Ferguson, University of Kent; Elisabeth E. F. Bradford, University of Kent and University of Dundee; and Camilla Woodrow-Hill, University of Manchester.