Yawning May Help the Brain Chill Out The purpose of yawning is
hotly debated, but new study suggests people yawn to cool the
brain FRIDAY, Sept. 30 (HealthDay News) -- Yawning may be a
natural way of regulating brain temperature, a new study
suggests. U.S. researchers examined the frequency of yawns among
80 people in the winter and another 80 people in the summer and
found seasonal variations. Yawning is known to be "contagious,"
the researchers pointed out. After being showed pictures of
other people yawning, nearly half of the participants yawned
while outdoors in winter, compared with less than one-quarter
while outdoors in summer, according to the report published
online Sept. 22 in the journal Frontiers in Evolutionary
Neuroscience. The finding that people yawn less often in the
summer, when outdoor temperatures often exceed body temperature,
suggests that yawning could be a natural brain-cooling
mechanism, said the researchers at Princeton University and the
University of Arizona. "This provides additi