Optogenetics is a technique developed in 2006 that uses light to control neurons by inserting light-sensitive ion channel genes into brain cells. It works by using channelrhodopsin genes to excite neurons or halorhodopsin genes to inhibit neurons when light hits the nerve cell. This allows precise activation or stopping of specific neuron groups with high temporal resolution. Optogenetics offers potential treatment for conditions like anxiety, addiction, chronic pain, and sleep disorders by providing a less invasive way to stimulate or inhibit neurons compared to electrical methods. However, challenges include introducing foreign genes into the brain and technical issues like fiber optics posing infection risks or requiring heavy batteries.

1. Optogenetics
A Light Switch for the Brain
Derek Schweighart

2. History
Optogenetics is the integration of optics and
genetics to achieve gain of previous loss of function
of events within cells of living tissue
Optogenetics was first invented in 2006 at Standford
by Karl Deisseroth, MD

3. How it works
Use channel rhodopsin gene to excited the nerve
when light hits the nerve
Use halo rhodopsin gene to inhibited the nerve when
light hits the nerve

5. Six Steps of Optogenetics
Create a genetic construct
Insert construct into virus
Inject virus into
Insert optrode fiberoptic cable plus electrode
Laser light opens ion channel in neurons
Record behavioral results

6. Pros
Optogenetics is less invasive than electrical
stimulation
Response time is faster than other treatments
Activate or stop certain groups of neurons in the
circuits with a precise electrophysiology

7. Sequence

8. Possible cures for:
Anxiety
Addiction
Chronic pain
Sleep disorders
Attention Deficit Disorder
Migraine

9. Cons
Limitations include the introducing a foreign gene
into the human brain
Fiber optics could pose the threat of infection and
being uncomfortable and having to carry heavy
batteries
Cost
Reports of depression and causing falls

10. Video
http://www.ted.com/talks/ed_boyden.html

11. Discussion questions
What other conditions could optogenetics help?
How could it made safer to humans?
How could less foreign (ie) human genes be used in
optogenetics?
How could it be run without batteries?

12. Sources
http://www.scientificamerican.com/article.cfm?id=optogenetics-
controlling
http://www.nature.com/news/2010/100505/full/465026a.html
http://www.huffingtonpost.com/ruth-starkman/optogenetics-a-new-
techno_b_1700219.html
http://www.nature.com/nmeth/journal/v8/n1/full/nmeth.f.324.html
http://dujs.dartmouth.edu/wp-
content/uploads/2011/03/19_pdfsam_11w_final.pdf