Fig. 1.
Four different techniques for manipulating neural activity. Each of the techniques described in this Readers’ Toolbox article excite or inhibit neural activity via their effects on membrane-bound proteins, including voltage-gated proteins (A), ion channels (B) or other receptors opsins (C), and modified receptors (D) that respond to an exogenous ligand instead of their endogenous ligand. Because of their different molecular mechanisms, these four techniques exhibit varying degrees of spatial range, temporal dynamics, and neuron-type specificity. Researchers use these techniques for manipulating neural activity to study the role of neural circuits in a range of physiologic, behavioral, and cognitive states.