Table 2.

Technique	Action	Timecourse	Specific approach	Effect on neuron	Citation
Diphtheria toxin	Activation of the diphtheria toxin receptor by diphtheria toxin induces cell death via inhibition of protein synthesis	Permanent	NA	Cell death	Buch (2005) Huang (2013)
DREADDs (Designer Receptors Exclusively Activated by Designer Drugs)	Mutated muscarinic receptors that are activated by the otherwise inert ligand clozapine-N-oxide (CNO) to increase G- protein coupled receptor signaling cascades and alter neuronal function	Minutes to hours	hM4D(Gi)	Activation of Gi/o signaling cascades leads to a reduction in neuronal firing	Urban & Roth (2014) Ferguson & Neumaier (2015)
			rM3D(Gs) hM3D(Gq)	Activation of Gs or Gq signaling cascades leads to an increase in neuronal firing
Fast-scan cyclic voltammetry (FSCV)	Electrochemical technique used to detect changes in the concentration of extracellular dopamine	Subsecond	NA	None	Willuhn (2010) Robinson (2003)
In vivo calcium imaging	Measures changes in the concentration of intracellular calcium via fluorescent microscopy	Millisecond	Rhod	Rhodamine-based indicator that increases fluorescence when bound to calcium	Grienberger & Konnerth (2012)
Optogenetics	Optical activation of light sensitive channels (opsins) triggers or inhibits action potentials	Millisecond	Channelrhodopsin (ChR2)	Optical stimulation of neuronal activity by increasing intracellular sodium	Tye & Deisseroth (2012) Zalocusky & Deisseroth (2013) Allen et al (2015)
			Archaerhodopsin (Arch)	Optical inhibition of neuronal activity by pumping protons out of cell
			Halorhodopsin (eNpHR)	Optical inhibition of neuronal activity by increasing intracellular chloride
Tetanus Toxin	Prevents neurotransmitter release from neurons expressing toxin by cleavage of vesicle associated membrane protein2 (VAMP2), which disrupts synaptic vesicle docking	Days to weeks	NA	Eliminates neurotransmitter release	Fowler & Kenny (2011)