New research reveals that the electrical stimulation of a brain structure in mice relieves behaviors related to autism, thus identifying a possible new treatment for the disorder.
One common symptom of autism spectrum disorder (ASD) is repetitive behaviors that sometimes lead to self-harm — such as when people bang their heads against the wall and bite or punch themselves continually. When these behaviors are severe they may not respond to conventional treaments, including medication and behavioral therapy. Sometimes they are addressed with some success with electroconvulsive therapy (ECT), a procedure that can perturb memory.
deep brain stimulation (DBS) successfully treated a mouse model of repetitive self-harm, with the potential for fewer side effects and less frequent anesthesia than ECT. The team was led by Irving M. Reti, M.D., and included BBRF Scientific Council member and 1997 NARSAD Independent Investigator grantee Jay M. Baraban, M.D., Ph.D. Both are at the Johns Hopkins University School of Medicine.
The researchers utilized genetically modified mice that engage in autism-like behaviors including unusually high levels of stereotyped self-grooming behavior which sometimes causes scarring. ECT reduced self-grooming in the mice, just as it reduces acts of self-harm among people with autism. The researchers tested DBS by implanting the brains of the mice with electrodes that applied electrical activity to a region called the subthalamic nucleus, a group of cells deep in the brain that helps to control movement.
This reduced excessive self-grooming in the mice, without impacting other movements or social behavior in the animals, suggesting that the effect is specific to repetitive self-harm. Moreover, the stimulation showed an impact almost immediately after being applied, and worked even more quickly the second time the mice underwent the procedure. This finding raises the possibility that the brain becomes sensitive to stimulation of the subthalamic nucleus, such that the electrical activity could be applied less often over time to achieve the same therapeutic effects.
The experiments, more broadly, support the idea that repetitive self-harm in humans stems from irregularities in the brain’s motor control center (a collection of structures called the basal ganglia). More studies using deep brain stimulation can further elucidate the nature of these behaviors, the researchers say.
Read the paper.