Study shows college students have less empathy when they are less alert

A new study to be presented at the SLEEP 2024 annual meeting, held in Houston, Texas, June 1–5, found robust evidence that implicates lower alertness, a key outcome of insufficient sleep, as a predictor of muted empathic responding, which suggests alertness may support both cognitive and affective empathy.

Results show that slower response times on objective alertness tests were significantly associated with lower levels of empathic concern, and that lapses and false starts on these tests were significantly associated with poorer empathic accuracy. Additionally, those who were more objectively alert reported significantly higher affective empathy than the control group.

"Affective empathy is the ability to feel emotions in concordance with another, and cognitive empathy is the ability to understand what another is feeling," said lead author Breanna Curran, who is a psychology graduate student at Iowa State University in Ames, Iowa. "Slightly less alert individuals exhibited muted affective empathy, while only individuals who exhibited attention lapses exhibited poorer cognitive empathy."

Sufficient, healthy sleep is associated with better health outcomes, including improved attention, behavior, learning, memory, emotional regulation, quality of life, and mental and physical health. The American Academy of Sleep Medicine and Sleep Research Society recommends that adults should sleep 7 or more hours a night on a regular basis to promote optimal health.

The researchers collected data from more than 800 college students across three studies. In all three studies, participants first reported on their subjective alertness using the Karolinska Sleepiness Scale, and their objective alertness was measured using the Psychomotor Vigilance Test. Participants then completed the Multifaceted Empathy Test to measure cognitive and affective empathy.

Study 2 replicated Study 1 using more diverse stimuli, and in Study 3 participants were randomly assigned to ingest 300 mg of caffeine or a placebo before completing the tasks. All participants then completed an additional affective empathy test.

Curran noted that the relationship between alertness and both an individual's empathic accuracy and concern helps us to better understand the driving mechanism behind why sleep disruption harms an individual's ability to empathize.

"In an applied setting, this novel finding can aid understanding of an individual's lack of empathy and can inform recommendations for those whose empathy is essential to their occupation," Curran said.

The research abstract was published recently in an online supplement of the journal SLEEP and will be presented Tuesday, June 4, during SLEEP 2024, the annual meeting of the Associated Professional Sleep Societies, a joint venture of the American Academy of Sleep Medicine and the Sleep Research Society.