Figure 1.

Top row: Mean DPOAE (squares) and noise (triangles) levels in dB SPL as a function of suppressor level, L₃, in dB SPL. Bottom row: Mean DPOAE decrements (circles) in dB as a function of L₃. Left column shows data when f₂=500 Hz; right column shows data when f₂=4000 Hz. In both cases, L₂=40 dB SL, and an on-frequency suppressor (f₃) was used (f₃=515 and 4100 Hz for f₂=500 and 4000 Hz, respectively). Closed symbols represent the transformed data points and the line represents a linear regression fit to the closed symbols. In all cases, error bars represent ±1 s.d. The short vertical dashed lines in the bottom row of panels are drawn at a decrement of 3 dB, which was used as suppression threshold for the construction of STCs.