Amplitude curve (left panel) and phase curve (middle panel) for one ANF, obtained from a single response to a multitone stimulus. The magnitude of the amplitude curve, determined by the relative vector strength of each stimulus component, was corrected for the frequency dependence in phase locking (see text), after which its maximum was arbitrarily set to zero. To reveal details in the associated phase curve (middle panel), an overall delay was compensated for by advancing the curve in time by 2.1 ms (right panel). The CF (1.90 kHz), obtained from single tone data, is indicated in each panel (filled circles). The zwuis-stimulus consisted of 20 frequency components (0.93–2.5 kHz), each component at 15 dB SPL. The gap in amplitude and phase curves at 2.41 kHz corresponds to a stimulus component that failed to yield significant phase locking (Rayleigh test, p > 0.001).