How About We Use Ultrasound Instead of Light?

About a month ago, Dr. Stephan Steidl had come in to talk to us about his studies using optogenetics, which is the use of light to stimulate specific brain cells. A wide used tool in neuroscience, optogenetics is a technique used to help figure out and give us an idea of how the nervous system works by allowing one to have extreme precision in what specific type of brain cell and at what point during a neuron's action potential he or she would like to study. In order to pass light through living tissue, however, there must be an insertion of a thin fiber optic cable which will then pass the light through to the brain. Ouch. Recently though, it was found that one could possible conduct the same function of optogenetics with the use of ultrasound, in a technique called sonogenetics.

Unlike optogenetics, sonogenetics has not yet been tested on mammals, but it has been tested with the microscopic worm, C. elegans, which do not have brains but do have neurons at a complexity level close to ours. According to Sreekanth H. Chalasani of the Salk Institute of San Diego, along with genetic modifications, it is possible for precise neurons to be targeted using ultrasound. Therefore, the same goal of optogenetics can hopefully in the future be achieved using sonogenetics in which one would no longer have the need to insert the fiber optic cable, but could simply use the safer method using ultrasound. This could possible even open the doors to finding out the locations and connections of each and every neuron in our heads.

C. elegans connectome of neurons

As mentioned earlier, sonogenetics has not yet been tested with mammals, but Dr. Chalasani does seem quite optimistic for the future and is looking to attempt doing so by using genetic modification in order to create the channels that are needed in order for the specific neurons to be targeted with the ultrasound. It seems as though optogenetics will still be around for a while and will be continued to be used in order to study the nervous system for now, as still more research must be conducted in order to find out if sonogenetics does, in fact, have the ability to work on mammals such as mice.

Works Cited

Deisseroth, Karl. "Optogenetics: Controlling the Brain with Light." Scientific American. Web. 15 Oct. 2015. <http://www.scientificamerican.com/article/optogenetics-controlling/>

Gorman, James. "Testing Neurons With Ultrasound." The New York Times. 28 Sept. 2015. Web. 14 Oct. 2015. <http://www.nytimes.com/2015/09/29/science/testing-neurons-with-ultrasound.html?action=click&contentCollection=science&region=stream&module=stream_unit&version=latest&contentPlacement=86&pgtype=sectionfront>

Picture: http://www.scientificamerican.com/article/c-elegans-connectome/