Students might have a new excuse for forgetting what they studied come exam time.

Research conducted by the National Institute of Mental Health and Yale University shows that stress may lead to short-term memory loss.

The study found that high amounts of the enzyme protein kinase C, or PKC, which rises when a person is stressed, can impair working memory, according to Dr. Husseini Manji, head of the Mood and Anxiety Disorders Program at the National Institute of Mental Health.

Manji, who helped conduct the study, said normal levels of PKC exist in the brain to help nerve cells release neurotransmitters and are needed to function properly. Too much PKC is what leads to problems. He said stress tends to activate levels of PKC, which prevent cells from working correctly.

"It screws up the ability for nerve cells to function," he said. "They fire erratically and short-term memory is one thing that can be affected."

The discovery of the negative impacts of excessive PKC could lead to better treatments of people who suffer from bipolar disorder and experience mania from high stress levels, Manji said.

"Many people who have bipolar disorder right now become very manic and treatments take weeks to work," he said. "PKC inhibitors could treat them right away in the emergency room."

Eventually, people with bipolar disorder could carry PKC inhibitors with them to prevent manic attacks, Manji said. He hopes the research will continue to develop into better treatments.

"We think it will have a huge benefit if it works," he said. He said treatments to reduce PKC levels are being considered mostly for people who have mental disorders.

People with mental health disorders are not the only ones affected by excessive PKC levels. Since stress can activate PKC, college students can become susceptible to its concurrent side effect of memory loss.

Jeanne Bulgin, counselor at Marquette's Counseling Center, said stress is one of the main reasons why students come to the center.

"Last year we saw over 700 individual students, and all of them were stressed in some way," she said. She added the center has seen an increase in student visits so far this year.

Bulgin agrees stress can be linked to forgetfulness. She said this likely occurs because of a lack of concentration that accompanies stress.

"It may not be memory loss that is associated with stress as much as a difficulty encoding things in your memory because you are distracted from the information," she said.

Julie Schmelzer, a freshman in the College of Communication, said her stress level fluctuates depending on what is going on in her classes.

She said she does forget things sometimes when she is particularly stressed.

"When it comes to the test, you can cram for it and know that you know it, but you just can't remember," Schmelzer said.

Still, students should not prepare to blame poor performances on all exams on their high level of stress.

Dr. E. Fuller Torrey, associate director for laboratory research at Stanley Medical Research Institute, said he would not make the direct link between excessive stress and memory loss among most people.

He said even among people with bipolar disorder, the link between extreme stress and impaired memory is uncelar.

"What they have in common is that abnormal PKC levels can interfere with working memory," he said. "Stress is known to exacerbate but not cause bipolar disorder."

Along with those suffering from bipolar disorder, students looking for excuses for their forgetfulness will have to wait a little longer to see if stress is indeed a viable culprit.