Photocontrol of neural activity: biophysical mechanisms and performance in vivo.

A discussion regarding the various photomanipulation technologies demonstrated in the nervous system is given with a focus on the biophysical mechanisms and with their limitations with its performance. Topics being reviewed include photoablation and photoinactivation as well as the photomanipulation of membrane potential. Under photoablation and photoinactivation are more specific topics which include: the cellular targets with dye-mediated photoablation and the genetically targeted small molecule photoablation. As for molecular targets, the chromophore-assisted light inactivation (CALI) will be used. Under photomanipulation of membrane potential, topics that will be described will include: the role of ion-selective conductances; the effect of background synaptic activity; the thermal photostimulation; the reactive oxygen species-mediated photostimulation; the caged glutamate and GABA; and finally, the genetically encoded photomodulators of membrane potential