Slow IPM sweeps evoke transient P1-N1-P2 responses while faster rates evoke steady-state following responses.

Evidence

Figure 2 shows responses analysed in the time domain (left panels) and the frequency domain (right) for a single IPM condition (±67.8°). Individual (gray lines) and group mean (black) for the slowest IPM rate (3.4 Hz; Fig. 3 , top ), typically displayed a P1-N1-P2 response to each IPD transition, with component latencies of approximately 50, 100 and 175 ms, respectively. The next two harmonics (6.8 and 10.2 Hz) were also observed clearly in the response to the 3.4-Hz IPM. Evoked responses to the intermediate IPM rate (6.8 Hz; Fig. 2 ) became steady state at the same rate as the IPM, and so we term this response the IPM-FR. In the time domain (left-middle), the peak amplitude of the IPM-FR is broadly the same as that for the slowest IPM rate (3.2 Hz), but responses were more steady state than those at the low rate, being more consistent in phase and amplitude across epochs (evidenced by a more favourable SNR). — Dijk, Pim van, Physiology, Psychoacoustics and…, 2975

Categorization

• DEFINE: Defines the IPM-FR (interaural phase modulation following response) as the steady-state response at the IPM rate, contrasting it with the transient P1-N1-P2 to each transition.