Mapping Technique Allows Researchers to Identify Brain Network

A new report published in the August issue of The Journal of Clinical Investigation revealed that imaging techniques can be used to identify brain patterns that are abnormal or indicate disease. Investigators at The Feinstein Institute for Medical Research made use of a new image-based strategy to identify and measure placebo effects in randomised clinical trials for brain disorders.

Led by David Eidelberg, MD, a team of researchers at the Feinstein Institute's Center for Neurosciences developed a method of analySing brain patterns through imaging techniques. The technique has been successful in identifying specific networks in the brain which suggest that a patient is at a risk or has Parkinson's disease and other neurodegenerative disorders. Parkinson's disease is the second in the list of common neurodegenerative diseases in the U.S. The symptoms are varied; the patients may experience tremors, slowness, rigidity, difficulty in walking, impaired balance and coordination, depression and sleeping disorders. They have difficulty in performing simple daily household tasks.

To date, Parkinson's disease is diagnosed by a skilled healthcare professional who usually is an experienced neurologist. He determines through clinical examination the probability of someone going to develop the disease or has already developed and is suffering from it. There has been no cure found until now for the disease, medications have, however, proved to improve the symptoms.

Dr. Eidelberg pointed that one of the major challenges in developing new treatments for neurodegenerative disorders such as Parkinson's disease is that it is common for patients participating in clinical trials to experience a placebo or sham effect. "When patients involved in a clinical trial commonly experience benefits from placebo, it's difficult for researchers to identify if the treatment being studied is effective," he added.

Dr Eidelberg explained that in a new study that he and his colleagues conducted, they had used "a new image-based strategy to identify and measure placebo effects in brain disorder clinical trials."

In the study he conducted, the researchers sought to identify specific brain circuits underlying the response to sham surgery in Parkinson's disease patients participating in a gene therapy trial is using their network mapping technique. It was seen that "blinded" patients with favourable responses to fake surgery showed long-tern signs of activation within this network, while patients treated conventionally with psychoactive medication or that experienced further disease progression, showed no activation. "Several regions contributing to this network have previously been noted to exhibit increases in local activity in response to placebo," the study noted.

Finally, an individual subject's network expression value measured before the treatment predicted his/her subsequent blinded response to sham treatment. This suggests that this novel image-based measure of the sham-related network can help reduce the number of subjects assigned to sham treatment in randomised clinical trials for brain disorders by excluding those subjects who are more likely to display placebo effects under blinded conditions.