Optogenetics and the BRAIN Initiative: shining a light on the brain
Researchers can now control some behaviors in mice by shining light into their brains using technology developed in the field of optogenetics. Optogenetic experiments have been used to control the impulse to eat or movement in mice, as well as to control behavior in maggots and flies.
Current treatments for psychological disorders are imprecise. Drugs bathe the brain in chemicals which help alleviate the symptoms of a disorder but also end up having many side effects in the process. Some have found relief from electrical stimulators implanted in the brain, but this method is also imprecise, as electricity travels along the path of least resistance and may affect cells that are not the intended target . Such imprecise treatments of such a complex organ can lead to sometimes serious side effects.
Ideally, neuroscientists could go through the brain circuitry turning cells on and off to figure out what they do. Optogenetics enables researchers to explore the brain with an unparalleled level of precision by equipping individual neurons with photosensitive receptors that enable them to fire when hit with light. To equip neurons to respond to light, researchers use molecules that convert light into electricity, much like little solar cells. Neuroscientists then “install” these molecules on individual neurons using viruses and gene therapy. Once this is done, the now light-sensitive neurons will fire when hit with light.
Recently, wireless optogenetics has been developed through the BRAIN initiative, which “simplifies light delivery and paves the way for more natural behavior during optogenetic experiments” . Previously, light had been piped into the brain using clumsy devices implanted in the brain of a test subject and connected to a cable. Wireless optogenetics now allows the light delivery system to be implanted completely inside the brain, disconnected from a cable, which means researchers do not need to handle mice prior to experiments.
These advancements in neuroscience are made possible by the BRAIN initiative (Brain Research through Advancing Innovative Neurotechnologies), a massive, collaborative, private-public funded project aimed at better understanding the human brain. President Obama committed $100 million of the federal 2014 budget to the BRAIN initiative and has increased funding by $100 million each year since 2014 . This federal funding has been matched by the private sector funding each year since inception . The hope is that the BRAIN initiative may lead to the greatest scientific achievements of the twenty first century.
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4. Obama Administration Proposes Over $300 Million in Funding for The BRAIN Initiative. 2015. ed. Office of Science and Technology. www.whitehouse.gov/ostp.