Optogenetic experiments were performed by stimulating ChR2-infected excitatory neurons with 470 nm LED light (Thorlabs). Light evoked synaptic responses were recorded from central chamber neurons at a holding potential of −70 m V. All electrophysiological experiments were performed using a rig containing a Molecular Devices 700B amplifier (Molecular Devices), a Digidata 1400 A/D converter, a Sutter 385 manipulator and an Olympus IX50 with an infrared video camera. Data were filtered at 2 kHz and digitized at 5 kHz. Data were collected using pClamp10 software (Molecular Devices).
