Fig. 4.

Hit rate versus false-alarm rate. Lines join data collected within a single block of sessions. Colour differentiates signal SNR (dB) as indicated in the inset. (A) Method of Limits for F2. (B) Method of Constant Stimuli for F2. Lower panels (C, D) show data for all animals. Symbols differentiate ferrets; colour differentiates tone level, as in (B). Each point corresponds to the mean hit/false-alarm rate, for a given ferret, averaged across all blocks of sessions. Dotted lines mark chance (hit rate = false-alarms) performance and unbiased (hit rate = 1-false-alarms) behaviour. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)