Researchers release GAD study

Feb. 16, 2010, 1:00 a.m.

People with Generalized Anxiety Disorder (GAD) suffer from abnormalities in the way their brains control negative emotions, a new Stanford School of Medicine study found. These findings lend insight into how to better treat the disorder.

According to Amit Etkin, a professor in the School of Medicine, anxiety is normally healthy and adaptive. Patients are diagnosed with GAD only when their worries are “frequent, pervasive and uncontrolled.”

Moreover, patients suffering from GAD tend to avoid things that make the anxiety worse.

“An example is interpersonal conflict,” Etkin stated. “Someone may have said something negative and it may take [the GAD patient] hours of the day before they can get back to rebut their point. They’re just unable to deal with the negative emotions and their mind just spins and spins. They have a deficit in regulating emotion.”

Through the use of functional magnetic resonance imaging (fMRI), a way of monitoring brain activity by registering blood flow to active parts of the brain, Etkin and his team of scientists examined a part of the brain called the amygdala in 17 GAD patients and 24 healthy comparison subjects.

During the scan, the participants were shown a series of pictures of happy or fearful faces overlaid with the word “fear” or “happy.” To create a sense of emotional conflict among participants, the words and faces did not always match.

When the face and accompanying adjective did not match up, subjects took longer to identify the correct expression. The study found that healthy participants were able to adapt to the change quickly relative to GAD patients, who struggled when the preceding image was also incongruent.

A previous study published by Etkin in 2009 determined that the function of the amygdala region is altered in patients diagnosed with GAD.

According to this year’s study, the pregenual anterior cingulate, located in the prefrontal cortex at the front of the brain, lights up during times of emotional conflict among non-GAD patients to inhibit the amygdala, but fails to do so in GAD patients’ brains.

“[The amygdala] has been better studied in animals,” Etkin said. “We wanted to study it more in detail in people.”

These results are expected to lead to better diagnosis of anxiety disorders and the development of more effective strategies to deal with these disorders. Understanding and analyzing GAD is important for advancements in treatment.

“fMRI-using tasks like this that Amit [Etkin] developed and uses here could potentially be used not only as a probe to assess treatment efficacy, but also as biomarkers to predict prognosis and who may respond to particular treatments such as psychotherapy,” wrote Fumiko Hoeft, a psychiatry and behavioral sciences instructor in the School of Medicine, in an e-mail to The Daily.

A chronic disease, GAD can affect anyone, regardless of socioeconomic status, race or educational background. According to Ronald Albucher, the director of Counseling and Psychological Services (CAPS), approximately 13 percent of Stanford students seek help at CAPS. Anxiety is one of the top four reasons why they visit, along with depression, relationship problems and self-esteem issues.

“There were plenty of Stanford students in the study,” Etkin said. “We recruited all over the place.”

“There is no doubt that the environment at Stanford, like any other college, can contribute to worsening the symptoms [of anxiety],” Etkins added.

Nationally, 18 percent of Americans have an anxiety disorder, according to the National Institute of Mental Health.

“We know that anxiety disorders are one of the most common psychiatric disorders,” Albucher said. “The top and most common ones are anxiety and depression.”

“These results make sense,” he added. “We often see that anxiety leads up to depression, so if they are unable to regulate negative emotions then that explains the path leading to depression.”

Ivy Nguyen contributed to this article.

Login or create an account