Manipulating Neurons

optogenetics infographic_FOR WEB-06.png

With a flash of light, neuroscientists can now turn individual brain cells on or off. They do so using a set of tools, pioneered in part by UT Austin neuroscientist Boris Zemelman, called optogenetics. For the first time, scientists can see how sets of neurons work together in a healthy brain during learning and memory recall, as well as in disorders, such as Alzheimer’s, Parkinson’s, traumatic brain injury and addiction. Optogenetics is producing insights that could uncork a flood of new therapies. 

It’s been 15 years since Zemelman and neuroscientist Gero Miesenböck at Memorial Sloan-Kettering first discovered a way to genetically modify nerve cells so they would respond to light. Zemelman’s lab now uses optogenetics to both perturb and track neuronal activity. 

In a first-of-its-kind study coauthored with Eyal Seidemann, another UT Austin neuroscientist, researchers have even analyzed neurons’ activity in primates engaged in a cognitive task. Experiments like these bring scientists closer to understanding the human brain.

Read more on how Zemelman and a team are working to map the brain’s activities.

Optogenetics in practice

Scientists use viruses to express foreign proteins in neurons of a living animal, so that the brain cells either sense or emit light. Light-sensing relies on proteins called opsins. 

optogenetics infographic_FOR WEB-01.png

The opsins are inserted into specific brain cells in the animal. 

optogenetics infographic_FOR WEB-02.png

Blue light activates neurons

optogenetics infographic_FOR WEB-03.png

Now when a certain color light illuminates these neurons, the opsins respond to the light and activate the neurons — turning them on like a light switch. 

optogenetics infographic_FOR WEB-04.png

Zemelman’s team is using this technology to map brain circuits, identifying sets of neurons that carry out tasks, such as seeing or hearing, or experiences, like learning or addiction.