Optogenetics is a relatively new field of
neuroscience that involves gene therapies applied to animal models that creates light
sensitivity in the function of specific neuronal circuits in the brain. And specifically it
allows you to use exposure to light to control behavioral responses, and to untangle complex
neuronal circuits by specifically targeting – turning on and off – specific classes
of cells within the brain. Strategic implementations of these optogenetic ideas allow one to tease
out the behavior of the brain, especially conducted with these kinds of technologies
that can lead to insights into Alzheimer’s disease, Parkinson’s disease. But for an application like Optogenetics or
other investigations of the brain, you’d like to be able to deliver that electronics
down into the depth of the brain, and the question is, how do you do that? And we think
we’ve come up with some strategies that allow some powerful capabilities in that realm
that involve ultra-miniaturized devices, very thin flexible geometries, that can be delivered
down into the brain, or into other organs. So this is one of the devices that we have
built. So the actual devices and all the actual components are at the very tip of this thin,
filamentary structure. It’s small enough to fit through the eye of a needle, for example.
This entire system mounts on a miniaturized needle device with a dissolvable biocompatible
adhesive. So you can use the needle to inject these devices down into the brain, the adhesive
dissolves away, and you simply remove the needle, leaving behind classes of very advanced
optoelectronic systems that have cellular scale dimensions. So this is where all of the active components
are located. They’re connected via very tiny wires to this power module which mounts
on the outside of the animal. And it consists of an antenna and a rectifier circuit that
allows you to deliver power to the device using RF energy, similar to energy that comes
out of your cell phone. This device harvests that energy, and then delivers it down to
turn on and off the electronics and the LEDs that are located at the tip end of this device,
down into the depth of the brain. So the antenna allows the animal to move freely
within its cage or within the space of the room. The releasable plug can allow disassembly
of the overall system, so that the animals only need to accommodate this part of the
device when experimentation is not underway. So the LEDs that we typically use are blue
in color – that activates this light-responsive region of the brain to induce the release
of dopamine, so that creates a pleasurable response in the animal. And the release of
that dopamine can then be used in a training process to create desired behavioral responses
in the animal without any type of physical reward, just a reward induced by this light-activated
release of dopamine in the targeted cells. And then I think, longer-term, there is some
potential to use these techniques in a therapeutic manner. So the gene therapy approaches that
are used to create this photo-responsivity in animal models are not too different from
the gene therapy approaches that are being used in early clinical trials with humans.
So I think there is a longer-term potential for direct impact on human health in a therapeutic
sense, but certainly the immediate opportunities are in fundamental studies of neuroscience.

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