Light Treament On The Brain To Reduce Nerve Pain

Today's interesting post from sciencedaily.com (see link below) looks at how a small area of the brain can be stimulated by directed light frequencies to control pain signals in the neurons. The difficulty lies in making sure that we still sense the pain signals that we need to sense (touching a hot surface, avoiding injury etc) and that not all pain signals are 'switched off' by the process. The ever-heroic lab mice are the current recipients of the research but hopefully it will eventually translate into something practical that humans can use. It would certainly be less invasive than many other treatments.

Optogenetic stimulation of the brain to control pain demonstrated in study 
Date: February 26, 2015 Source: University of Texas at Arlington 

Summary:

New research reveals for the first time how a small area of the brain can be optically stimulated to control pain. Researchers found that by using specific frequency of light to modulate a very small region of the brain called the anterior cingulate cortex, or ACC, they could considerably lessen pain in laboratory mice.

A new study by a University of Texas at Arlington physics team in collaboration with bioengineering and psychology researchers shows for the first time how a small area of the brain can be optically stimulated to control pain.

Samarendra Mohanty, an assistant professor of physics, leads the Biophysics and Physiology Lab in the UT Arlington College of Science. He is co-author on a paper published online Wednesday by the journal PLOS ONE.

Researchers found that by using specific frequency of light to modulate a very small region of the brain called the anterior cingulate cortex, or ACC, they could considerably lessen pain in laboratory mice. Existing electrode based ACC stimulation lacks specificity and leads to activation of both excitatory and inhibitory neurons.

"Our results clearly demonstrate, for the first time, that optogenetic stimulation of inhibitory neurons in ACC leads to decreased neuronal activity and a dramatic reduction of pain behavior," Mohanty said. "Moreover, we confirmed optical modulation of specific electrophysiological responses from different neuronal units in the thalamus part of the brain, in response to particular types of pain-stimuli."

The research focused on chemical irritants and mechanical pain, such as that experienced following a pinprick or pinch. Mohanty said the results could lead to increased understanding of pain pathways and strategies for managing chronic pain, which often leads to severe impairment of normal psychological and physical functions.

"While reducing the sensation for chronic pain by optical stimulation, we still want to sense certain types of pain because they tell us to move our hands or legs away from something that is too hot or that might otherwise hurt us if we get too close," Mohanty said.

Young-tae Kim, a UT Arlington associate professor of bioengineering and study co-author, said the research could "possibly lead to less invasive methods for treating more severe types of pain without losing important emotional, sensing and behavioral functions."

Story Source:

The above story is based on materials provided by University of Texas at Arlington. Note: Materials may be edited for content and length.

Journal Reference:
Ling Gu, Megan L. Uhelski, Sanjay Anand, Mario Romero-Ortega, Young-tae Kim, Perry N. Fuchs, Samarendra K. Mohanty. Pain Inhibition by Optogenetic Activation of Specific Anterior Cingulate Cortical Neurons. PLOS ONE, 2015; 10 (2): e0117746 DOI: 10.1371/journal.pone.0117746

http://www.sciencedaily.com/releases/2015/02/150226101656.htm