Yes, light-induced activation of neurons sounds very interesting. One of hte papers came out just a few months ago. It is still in its early stages, the mice they used for their experiments seem to be transgenics made with a protein that responds to the light. If it has to work for humans I think they have to figure out a way to identify and activate neurons that need stimulation. It is interesting and definitely worth following!

More info on this subject:
Light Switch for the Brain
Scientists have developed a light-triggered switch to control brain cells, which could aid in the development of therapies for epilepsy and other diseases--and shed light on the neural code.
By Emily Singer
If clicking on the title above does not work, paste the link below into your web browser:
http://www.technologyreview.com/biomedicine/18488/

Karl Deisseroth is the person at Stanford who pioneered this work. His info if anyone is interested:
E-mail: deissero at stanford.edu

Associate Professor of Bioengineering
Associate Professor of Psychiatry and Behavioral Sciences
318 Campus Drive West
Clark Center W083
Department of Bioengineering
Stanford University
Stanford, CA 94305


Education
2000 Ph.D. in Neuroscience, Stanford University
2000 M.D., Stanford University
1992 A.B. in Biochemical Sciences, Harvard College

Professional Positions
01/09 - Present Associate Professor of Bioengineering and Psychiatry, Stanford Univ
01/06 - Present Diplomate, American Board of Psychiatry and Neurology
01/05 - 12/08 Assistant Professor of Bioengineering

Girija