Spike-Threshold Adaptation Predicted by Membrane Potential Dynamics In Vivo
a, Intracellular recordings () in the owl's ICx, with binaural stimuli (L: left, R: right). Either ITD is varied at best IID (top) or IID is varied at best ITD (bottom). Owl picture source: http://openclipart.org/detail/17566/cartoon-owl-by-lemmling. b, Two spikes from the traces in (a); red dots indicate the estimated spiking threshold. c, Trace from (a) shown in phase space: vs. . Spike threshold is detected when exceeds a fixed value (red dashed line). d, Distribution of subthreshold membrane potential (blue) and spike threshold (green). e, Spike threshold vs. average before spike. f, Spike threshold vs. depolarization slope before spike. g, Spike threshold vs. preceding interspike interval. Red lines are linear regressions.