Mind control is no longer limited to science fiction, but has expanded to neuroscience labs nationally.
With just an orb of blue light, some light-reactive proteins from algae, and a thin cable, scientists can now activate specific parts of the brain in mice.
Optogenetics, the genetic insertion of light-activated proteins originally found in bacteria into other organisms, allows scientists to activate areas of the brain where the protein is present. With the ability to turn on or off specific types of neurons, or brain cells, this technique has led to the identification of previously unknown underlying causes for behaviors found in humans.
For instance, through activating neurons within the medial prefrontal cortex of the brain, scientists are able to initiate antidepressant-like responses from mice. Results like this provide insight to locations that may be targeted in future treatments for depressive disorders.
“Optogenetics may be the answer to a search for temporal and spatial specificity in neuroscience,” says a team of researchers at the Leiden Institute for Brain and Cognition.
Previous techniques to find the function of specific neurons have forced scientists to prioritize either controling the timing of activation or the kinds of neurons activated. But with optogenetics, scientists are now able to dictate both the timing and location of activation.
These light-sensitive proteins, called opsins, are inserted into the mice through a virus that adds the genetic information necessary for the opsin to be produced in chosen neurons. Once these proteins are present, scientists can shine a laser light through a thin fiber attached into the skull of the mouse to activate the opsin-containing cells.
The accuracy and specificity of optogenetics has allowed scientists to target neurons without disturbing the surrounding areas. Because of this, the results of optogenetic testing have identified specific neurons and their roles in activities such as sleep, the processing of drugs, and in brains suffering from depression.
“Results like these show that the use of optogenetics can lead to a better understanding of cause-effect relationships,” says Leiden Institute.
However, optogenetics has so far only been used with animal models; research using human models is far from present, with the potential inflammation caused by the optic fiber insertion and the long-term consequences of direct light exposure on neurons.
The invasiveness of the treatment, however, may soon be lessened. A study published in Nature Communications earlier this month from the Institute of Basic Science revealed a genetically modified opsin with an increased sensitivity to blue light. With the mere shining of the light onto the outside of the mouse skull, neurons with the opsin were activated.
This decreased invasiveness of optogenetics may allow for advanced discovery within the field of neuroscience.
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https://doi.org/10.1038/s41467-019-14005-4.
https://doi.org/10.3389/fpsyg.2013.00610
Science Journalism- Abby Vogeley 