GABAergic mechanisms for shaping transient visual responses in the mouse superior colliculus.

摘要: An object that suddenly appears in the visual field should be quickly detected and responded to because it could beneficial or harmful. The superficial layer of superior colliculus (sSC) is a brain structure capable such functions, as sSC neurons exhibit sharp transient spike discharges with short latency response appearance stimulus. However, how activity generated poorly understood. Here, we show inhibitory inputs actively shape sSC. Juxtacellular recordings from anesthetized mice demonstrate almost all types neurons, which were identified by post hoc histochemistry, discharges, i.e., ON activity, immediately after stimulus onset. was followed pause before turned off. To determine whether reflected absence excitatory drive conductance, injected depolarizing currents juxtasomally, enabled us observe inhibition decreased discharges. observed even under this condition, suggesting input caused pause. We further found local application mixture GABAA GABAB receptor antagonists additively diminished These results indicate GABAergic produce responses attenuating through cooperative activation receptors, allowing act saliency detector.