Signal uncertainty and psychometric functions in profile analysis.
Experiment 1 was conducted to compare the effects of signal frequency uncertainty on the detection of a change in spectral shape and on the detection of a tone in wideband noise. Results indicate that for both tasks the uncertainty effect was small, being on average about 3 dB. In a second experiment, psychometric functions were measured for the detection of changes in the spectral shape of multicomponent complexes. Psychometric functions for profile tasks have a 25-dB range and are similar to those measured for the detection of an increment in the level of a single sinusoid. These psychometric functions are different from those found when detecting a signal in noise, which typically have a 10-dB range. Three equations for the shape of the psychometric functions were compared. The difference in the resulting fits was small, thus preventing an unambiguous choice of functional form.
Raney
J J
JJ
Department of Psychology, University of Florida, Gainesville 32611.
Richards
V M
VM
Onsan
Z A
ZA
Green
D M
DM
D000161:Acoustic Stimulation; D001306:Auditory Pathways / Q000502:physiology*; D006801:Humans; D010898:Pitch Perception / Q000502:physiology*; D011601:Psychophysics