Understanding Pitch Perception as a Hierarchical Process with Top-Down Modulation
Figure 5
Response of the model to stimuli used in the Hall and Peters' experiment [14].
(A) Spectrogram of a rapid sequence of three 40-ms tones presented in quiet (left panel) and after the addition of white noise (right panel). (B) Response of the third stage of the model, A3(t,l), for the stimulus in quiet (left panel) and in noise (right panel). In the noise condition, the response represents the average over three different random realizations of the noise background. Different colours represent activation strength as a percentage of the maximum response as in previous figures. Arrows indicate the lowest pitch reported by listeners in each condition. (C) Snapshot of A3(t,l) at the end of the stimulus (tfinal) in quiet (left panel) and in noise (right panel). Vertical dashed lines correspond to the final predicted pitch.