The field of optogenetics involves using light to control cells in living tissue such as neurons. Lately, scientists within this field have been working to modify the DNA of neurons so that they either send signals, or are blocked from firing, depending on how much light they receive.
A research team at Stanford University used mice to investigate how to control nerves outside of the brain. There are thousands of nerve endings just under the skin that respond to heat or pressure, and a bright handheld light could theoretically be used control these nerve endings.
The Stanford group first used gene therapy to plant light-sensitive molecules in nerve endings in the mice. They found that exposure to blue light caused the mice to flinch, cry out, or lick their paws, all signs of pain. However, exposure to yellow light, designed to block nerve impulses, caused the mice to be unbothered or slow to react to painful actions such as pinching or being subjected to hot infra-red beams.
The group’s latest work has been published in the journal Nature Biotechnology, and is extremely relevant considering the number of adults suffering from chronic pain. In the future, this type of technology could help treat those who are suffering from pain without causing the harmful side effect of addiction to pain-relieving medication.
Although the potential for optogenetic technology is present, there are still obstacles preventing it from becoming a reality. One such difficulty, for example, is that it might be hard to reach the appropriate nerve cells with light. In addition, this process relies on gene modification, which in itself is still in the experimental stages.
Regalado, Antonio. (2014, February 16). For Mice, and Maybe Men, Pain is Gone in a Flash. Retrieved November 12, 2015, from http://www.technologyreview.com/