Tests on the influence that a stress-related hormone has on learning in ground squirrels could have an impact on understanding how it influences human learning, according to a University of Chicago researcher.
Jill Mateo, Assistant Professor in Comparative Human Development, has found that when they perform normal survival tasks, ground squirrels learn more quickly if they have a modest amount of cortisol, a hormone produced in response to stress, than those with either high or low levels of cortisol.
In humans, cortisol production is also related to stress and is known to have an impact on learning, but that impact is not well understood, Mateo said. The research on ground squirrels could point to additional avenues of research.
In order to survive, ground squirrels must adapt quickly and learn how to navigate the dangers of their environment so they can find their way back to their burrows. Ground squirrel pups typically emerge from their burrows about the time theyre weaned, at four weeks of age.
Two hundred can emerge at the same time, providing a feast for predators, said Mateo, who studies Belding ground squirrels, native to high elevations in the western United States. In nature, about 30 percent of pups do not survive.
Modest levels of cortisol are apparently linked to their survival, Mateo reports in the article, Inverted-U shape relationship between cortisol and learning in ground squirrels, published in an on-line posting of the journal Neurobiology of Learning and Memory. The inverted U is the shape data forms on a chart. Animals with low levels of cortisol are at the left of the inverted U, and those with high levels are at the right, while those with modest levels and higher learning are in the middle.
In order to test whether animals with low levels have difficulty learning, Mateo simulated a natural setting with a maze and connected it with a box that contained a nest of squirrel pup
|Contact: William Harms|
University of Chicago