Extended Data Figure 1: Behavioural model.

a, Model that tests whether joystick releases depended on sound frequency, the amount of elapsed time, or a combination of the two. Joystick release times are predicted at a fixed time lag (Δt) relative to the occurrence of a fixed sound frequency (f₀). Schematic shows three trials that have different speeds of frequency traversal. Frequency f₀ occurs at different times relative to the press of the joystick across these trials. However, the time lag is constant. b, Model fits of the frequency component f₀ across all 189 behavioural sessions in nine rats. Red marks, median values for each of the rats. This frequency component accounted for most of the trial; indicated number is the median ± s.e.m. across rats. c, Model fits of the time lag component Δt across all behavioural sessions. This time lag component accounted for a small fraction of the trial; the lag might be largely explained by the expected reaction time (for example, 100–200 ms in pure-tone auditory discrimination tasks³⁹) and the mechanics of the joystick (300–400 ms). In other words, the behaviour was consistent with the rats responding to a frequency of ~13.5 kHz (just before start of the target zone at 15 kHz), resulting in a detectable release of the joystick ~750 ms later.