Connection found between degree of sleepiness and social interaction

A team of researchers from the Karolinska Institutet and Stockholm University has found a connection between how sleepy people are and how much they socialize. In their paper published in Proceedings of the National Academy of Sciences, the group describes their study of sleep and socializing patterns for a group of volunteers and what they learned from it.

Anecdotal evidence has suggested that when people are tired or sleepy, they are less willing to engage in most activities, social or otherwise. And prior research has shown that lack of sleep can lead to cognitive problems, a drop in motivation and behavioral changes. In this new effort, the team in Sweden wondered if there were more to the connection between sleepiness and social interaction. To learn more, they asked 641 working adults (in Sweden) to keep a detailed journal (with entries every 30 minutes when not working) of their sleepiness patterns and social activity for a three-week period.

While analyzing the data from the journals, the researchers found patterns suggesting there were previously unknown connections between sleepiness and socializing. They noticed, for example, that sleepiness and socializing were impacted by the time of day. They found that more social activity in the later parts of the mornings or early afternoons tended to make people sleepier later on. But oddly enough, engaging in more social activity in the evening led to reduced feelings of sleepiness later on. They also found that socializing in the later afternoon tended to push people to sleep a little longer that night. But socializing for a long time in the evening led to a shorter night's sleep. They also found that the impact can be dramatic; social contact can decrease by as much as 70 percent when people are sleepy.

The researchers suggest that their findings, when viewed as a whole, indicate that sleepiness in general leads to reduced desire to interact socially—most particularly during the times when it is possible to do so, such as after work or on weekends. The findings may help explain the increase in loneliness that has been widely reported in Sweden over the past several decades.