Looks like Ed Boyden may have another hit on his hands. He and Xue Han reported at the recent Cosyne 2007 meeting a new method of controlling neural circuits. You may remember his work on Channelrhodopsin-2, which gave us millisecond optical control of neuronal spiking. Now they have reported a complementary technique with millisecond optical control of neuronal silencing. From the abstract :
We report that cultured hippocampal pyramidal neurons expressing Halo-GFP under the CaMKII promoter experienced strong hyperpolarizations (> -20 mV) upon exposure to brief pulses of moderate-intensity yellow light (~565 nm). In the absence of light, Halo-expressing neurons were physiologically indistinguishable from wild-type neurons.
But wait! There’s more :
We also demonstrated that in individual neurons expressing both yellow-light driven Halo and the blue-light driven cation channel ChR2, neural inhibition and excitation could be efficiently and independently controlled at the millisecond timescale, by interleaving brief pulses of yellow and blue light.
Hey Ed! Leave some neuroengineering projects for the rest of us please. 🙂