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Evidence for direction-specific channels in the processing of frequency modulation.

R B Gardner·J P Wilson
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Abstract

Evidence is provided for the existence of at least three feature-specific channels in the auditory system. Thresholds for the detection of small repetitive or nonrepetitive frequency changes were measured following various adapting stimuli using a 2IFC procedure in two subjects at 1 kHz. Thresholds for single linear upward frequency sweeps (up sweeps) were increased by a factor of 2 to 3 following exposure to repetitive (8 Hz) up sweeps but not following exposure to down sweeps or tone bursts; correspondingly, thresholds for down-sweep stimuli were increased only by down sweeps. Sinusoidal FM test stimulus thresholds were elevated by both up-sweeps and down-sweeps and to a lesser extent by tone bursts. These results suggest the existence in the auditory system of channels specific to upward FM, downward FM, and probably repetition rate.

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R B Gardner, J P Wilson. 1979. Evidence for direction-specific channels in the processing of frequency modulation.. https://doi.org/10.1121/1.383220

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