Students who overeat as a way to deal with the stress of finals can blame it on biology, a new experiment shows.
The experiment, conducted by three researchers from the University of Michigan and Georgetown University, showed that lab rats with high levels of stress-related hormones craved sugar at three times the normal level.
The masses of students feasting in the Michigan Union during finals season shows the experiment has relevance beyond rats.
“When you’ve stayed up for a while, studying, and you’re hungry, you can’t help it,” Law School student John Le said.
University psychology professors Kent Berridge and Susana Pecina performed the experiment with help from Jay Schulkin, a physiology professor at Georgetown.
BMC Biology, a scientific journal, published their findings yesterday.
The researchers injected rats with corticotropin-releasing factor, a hormone and neurotransmitter produced by both rats and humans under stress. Released by the hypothalamus, CRF travels to a region of the brain called the nucleus accumbens, which controls the response to urges.
The researchers conditioned the rats to associate a noise stimulus with pushing a lever that released sugar pellets. When the researchers exposed the rats to the stimulus, the ones injected with CRF pushed the lever three times more often.
Pecina said the research team hoped to show a link between stress and “motivated behaviors” such as eating, recreational drug and alcohol use and sexual behavior in humans.
The stress of finals might drive students to make poor decisions about motivated behaviors, Pecina said.
“Finals week is tremendously stressful for the student population,” she said. “Students might find themselves engaging in behaviors they might not otherwise engage in.”
Engineering freshman Jonathan Wiebenga said the stress of studying for finals often leads him to eat more.
“I usually have food to snack on while I study,” he said. “Food comforts you somehow.”
Pecina advised that students worried about the consequences of stress should stay away from tempting environments if they hope to avoid harmful behaviors.
“Let’s say I quit smoking, but I enter a place I associate with smoking,” she said. “A high level of CRF might make it harder to resist the temptation.”