If the brain can be imagined as a giant switchboard with thousands of knobs, buttons, dials and levers that control aspects of emotions, behaviour, thought, and memory.
For more than hundred years, neuroscientists have been methodically alternating the switches on and off, alone or in combination, and trying to understand how the brain machinery works as a whole. This is not so simple, however. The cellular circuits that control mind and behaviour entangle together throughout the gelatinous mass of our brain, and do not have easy on/off switches for easy inverse engineering.
In a new development, scientists at the Wu Tsai Neurosciences institute, Stanford University have devised the first non-invasive method for controlling targeted brain circuits for behaviour of animals from a distance. The technique has the potential to present a solution for one of the biggest clinical needs in neuroscience: an approach to test the functions of particular brain cells flexibly and that of circuits deep in the brain during normal behaviour.
The findings of the study is published in Nature Biomedical Engineering.
Meanwhile, the newly developed technique is based on the principles of optogenetics. First devised at Stanford, the technique introduces light-responsive algal proteins into neurons to enable researchers switch them on or off in response to different colors of light.
Importantly, optogenetics has been transformative in neuroscience, however, it has limitations for what can be done with existing techniques. This is partly due to the dependence on light in the visible spectrum.
Physiologically, the brain is quite opaque to visible light, therefore it typically requires invasive optical implants for the light to reach the cells that need to be stimulated. The implants can cause tissue damage, and skull-placed fiber optic tethers that make it challenging to study many kinds of natural behaviour.
