On the DL for Frequency

Abstract

Difference limens for three frequencies (250, 1000, and 4000 cps) were determined for two trained observers by two psychophysical methods: the ABX procedure and the method of constant stimulus differences or AX procedure. Though the two observers differ considerably insensitivity, their DL's for the AX procedure are less than one-half of their DL's for the ABX procedure. Comparison of these data with data in the literature on DL's for frequency indicates a wide range of values for different psychophysical procedures and for different subjects. Some observations are reported that illustrate the effect of such factors as practice and ensemble of stimulus conditions upon the size of the DL. The influence of the stimulus ensemble upon judgement time is discussed briefly. In view of all the experimental data, it would be rather imprudent to postulate a “true” DL, or to infer the behavior of the peripheral organ from the size of a DL measured under a given set of conditions. While there is undoubtedly some relation between the size of the DL and the so-called channel capacity, there is little reason to assume that the relation is a particularly simple one, given the different operations by means of which these two quantities are determined.

Frequency discrimination as a function of frequency and sensation level

“…The Weber fraction, AF/F, is a nonmonotonic function of frequency with minima between 1000 and 2000 Hz for all sensation levels tested. Both the nonmonotonicity and the locus of best performance are similar to earlier descriptions of AF/F as a function of frequency at moderate SLs, e.g., about 40 dB (Harris, 1952;Moore, 1973;Nordmark, 1968;Rosenblith and Stevens, 1953 There is an orderly dependence of frequency 'discrimination on sensation level for pulsed sinusoids.…”

“…Recent studies on the discrimination of pulsed sinusolds have been restricted to a relatively narrow range of intensities and/or frequencies (Harris, 1952;Henning, 1967a, b;Moore, 1973;Nordmark, 1968;Rosenblith and Stevens, 1953). Therefore, we set out, as did Shower and Biddulph, to explore the effects of a broad range of signal levels and frequencies on frequency discrimination, but using pulsed sinusolds.…”

The perception of FM sweeps by Chinese and English listeners

“…Because the human perceptual system can be viewed as a binary signal detection system (UP or DOWN) during this 2AFC FM identification experiment, we further quantified the performance using Signal Detection Theory (SDT) by calculating d-prime, representing detector sensitivity, and b normalized , representing subject bias (Rosenblith and Stevens, 1953;Dorfman and Alf, 1968;Swets, 1982). Specifically, the Hit and False Alarm (FA) rates and corresponding d-prime (d 0 ) and b normalized were defined as follows:…”

The Discrimination of Pitch in Pulse Trains and Speech

“…Consistently, experiments in the perception of the pitch of pure tones have revealed that under certain conditions listeners can discriminate differences as small as about .3 Hz in the region of 100-250 Hz (e.g., Boring, 1940;Rosenblith and Stevens, 1953;Nordmark, 1968;Moore, 1974). However, most researchers have not attempted to examine pitch discrimination in speech or speech-like stimuli.…”