Science News
from research organizations

Mice give new clues to origins of obsessive-compulsive disorder

Date:
June 10, 2013
Source:
Columbia University Medical Center
Summary:
Researchers have identified what they think may be a mechanism underlying the development of compulsive behaviors. The finding suggests possible approaches to treating or preventing certain characteristics of OCD.
Share:
       
FULL STORY

Using a new technology in a mouse model, the researchers found that repeated stimulation of specific circuits linking the brain's cortex and striatum produces progressive repetitive behavior.
Credit: Image courtesy of Columbia University Medical Center

Columbia Psychiatry researchers have identified what they think may be a mechanism underlying the development of compulsive behaviors. The finding suggests possible approaches to treating or preventing certain characteristics of OCD.

OCD consists of obsessions, which are recurrent intrusive thoughts, and compulsions, which are repetitive behaviors that patients perform to reduce the severe anxiety associated with the obsessions. The disorder affects 2-3 percent of people worldwide and is an important cause of illness-related disability, according to the World Health Organization.

Using a new technology in a mouse model, the researchers found that repeated stimulation of specific circuits linking the brain's cortex and striatum produces progressive repetitive behavior. By targeting this region, it may be possible to stop abnormal circuit changes before they become pathological behaviors in people at risk for obsessive-compulsive disorder (OCD). The study, which was led by Susanne Ahmari, MD, PhD, assistant professor of clinical psychiatry at Columbia Psychiatry and the New York State Psychiatric Institute, was published in the June 7 issue of Science.

While the obsessions and compulsions that are the hallmarks of OCD are thought to be centered in the cortex, which controls thoughts, and the striatum, which controls movements, little is known about how abnormalities in these brain regions lead to compulsive behaviors in patients.

To simulate the increased activity that takes place in the brains of OCD patients, Dr. Ahmari and her colleagues used a new technology called optogenetics, in which light-activated ion channels are expressed in subsets of neurons in mice, and neural circuits are then selectively activated using light delivered through fiberoptic probes.

"What we found was really surprising," said Dr. Ahmari. "That activation of cortico-striatal circuits did not lead directly to repetitive behaviors in the mice. But if we repeatedly stimulated for multiple days in a row for only five minutes a day, we saw a progressive development of repetitive behaviors -- in this case, repetitive grooming behavior -- that persisted up to two weeks after the stimulation was stopped."

She added, "And not only that, when we treated the mice with fluoxetine, one of the most common medications used for OCD, their behavior went back to normal." The current study, as well as others currently being performed by Dr. Ahmari and her team, may ultimately provide clues for new treatment targets in terms of both novel drug development and direct stimulation techniques, including deep brain stimulation (DBS).

The study was supported by grants from NIMH (K08MH087718; K24 MH091555), the Louis V. Gerstner, Jr. Scholars Program, the Irving Institute for Clinical and Translational Research, the Gray Matters Foundation, the Leon Levy Foundation, and a NARSAD Young Investigator Award.


Story Source:

The above post is reprinted from materials provided by Columbia University Medical Center. Note: Materials may be edited for content and length.


Journal Reference:

  1. S. E. Ahmari, T. Spellman, N. L. Douglass, M. A. Kheirbek, H. B. Simpson, K. Deisseroth, J. A. Gordon, R. Hen. Repeated Cortico-Striatal Stimulation Generates Persistent OCD-Like Behavior. Science, 2013; 340 (6137): 1234 DOI: 10.1126/science.1234733

Cite This Page:

Columbia University Medical Center. "Mice give new clues to origins of obsessive-compulsive disorder." ScienceDaily. ScienceDaily, 10 June 2013. <www.sciencedaily.com/releases/2013/06/130610095150.htm>.
Columbia University Medical Center. (2013, June 10). Mice give new clues to origins of obsessive-compulsive disorder. ScienceDaily. Retrieved August 27, 2015 from www.sciencedaily.com/releases/2013/06/130610095150.htm
Columbia University Medical Center. "Mice give new clues to origins of obsessive-compulsive disorder." ScienceDaily. www.sciencedaily.com/releases/2013/06/130610095150.htm (accessed August 27, 2015).

Share This Page: