LGN electrophysiological recordings.

Whole-cell voltage-clamp recordings of dLGN neuron were performed using an EPC-10 amplifier (HEKA Elektronik) controlled by Patchmaster software. Recordings were carried out using a cesium methanesulfonate pipette solution contained (in mM): 100 CsCH₃SO₃, 20 KCl, 7 Na₂-phosphocreatine, 10 HEPES, 4 Mg-ATP, 0.3 GTP, and 10 EGTA, pH adjusted to 7.3 with KOH. The holding potential was −60 mV for AMPAR-mediated current and +40 mV for NMDAR-mediated current recordings in the voltage-clamp mode. Pipettes were pulled using an electrode puller (Model P-1000, Sutter Instruments) to open tip resistances of 4−5 MΩ. dLGN neurons and optic tract were identified based on neuronal tracer Dil (AAT Bioquest, Cat no. 22102, 2% w/v in DMSO) injected into the retina at P9²⁷. A bipolar electrode (Frederic Haer, Bowdoinham, ME) was placed in the optic tract then neurons in the dLGN were recorded. An Iso-Flex stimulator driven by a Master 10 pulse (<10 V constant voltage) was used. Data were analyzed offline and displayed with Igor Pro (Wavemetrics, Lake Oswego, OR).