摘要:

Magnitude estimates were obtained for the dissimilarity of pure tones varying in frequency and intensity. In Expt. 1, a spatial embedding for a set of seven tones was determined by assuming the magnitude estimates represented distances in a two‐dimensional space whose coordinate axes were pitch and loudness. Embeddings were determined for both Euclidean and “city‐block” distance functions. A linear relation was consistently observed between the projections of the tones on dimensions of pitch and loudness and their values on Stevens's mel and sone scales, with the city‐block projections usually yielding higher correlations. In Expt. 2, 11 tones were used and the magnitude estimates of dissimilarity were compared to the tightly constrained “monotone” distances derived from the rank‐order properties of the dissimilarities. The agreement observed between the magnitude estimates and the monotone predicted distances strongly supports a distance interpretation for the dissimilarities.

ISSN:0001-4966    

DOI:10.1121/1.1913042

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

The clinical literature indicates that some persons with sensorineural hearing impairment show temporal integration functions that have relatively flat slopes when compared to subjects (Ss) with normal sensitivity. It is not clear whether temporal integration functions with reduced slopes are due to sensorineural hearing impairmentper se, or to the relatively high levels of signal required to measure the thresholds of these hearing‐impaired Ss. Therefore, temporal integration functions were obtained from four normal Ss in the presence of a masking noise of sufficient over‐all level (87 dB SPLre0.0002 dyn/cm2) to simulate moderate to severe hearing loss. The results indicate that temporal integration functions with a reduced slope are a consequence of sensorineural hearing impairment and are not due to the relatively high levels of signal required to measure threshold.

ISSN:0001-4966    

DOI:10.1121/1.1913043

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

Subjects were presented with low‐frequency tonal signals, leading in time to one ear but more intense to the other. For differing values of interaural time (Δt) and intensity (ΔI), the listener's task was to detect the difference between the dichotic signals and diotic tones of the same frequency. The shapes of the psychometric functions demonstrate that time and intensity do trade but that the trade is incomplete—a result shown to be in accord with other experiments where listeners presented with such signals report the presence of two distinct “images.” A model of time‐intensity trading is presented in which it is assumed that differences of intensity are converted to time by two different trading mechanisms and that the two sums of Δtand converted ΔIact as different loci on a single interaural dimension. It is further suggested that the inner and outer hair cells may represent the site of the two trades.

ISSN:0001-4966    

DOI:10.1121/1.1913044

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

Two primary tones of frequencyf1= 368–1475 Hz andf2= 1.1–1.5 timesf1were presented monaurally at 60–80 dB sound‐pressure level. Nonlinear distortion products at bothf2−f1and2f1−f2were made to beat against low‐intensity probe tones slightly mistuned from the frequency of the distortion product. Subjects adjusted the amplitude and phase of cancellation tones at the frequency of the distortion product to eliminate the beating. The amplitude and phase of the2f1−f2cancellation tone agree with results already in the literature. The amplitude of thef2−f1cancellation tone relative to the primary tones is insensitive to amplitude of the primary tones. Both the amplitude and phase angle of thef2−f1cancellation tone decrease with an increase off1orf2/f1. Differences between properties of the2f1−f2andf2−f1cancellation tones are consistent with a model for generation of distortion products proposed by Goldstein.

ISSN:0001-4966    

DOI:10.1121/1.1913045

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

When two primary tones in the frequency ratiof1:f2 = 2:3are presented to human listeners, a combination tone is audible atf1/2. The loudness of this combination tone depends on the phase angle between the two primary tones. We measured the amplitude and phase of the combination tone using a cancellation‐ plus probe‐tone technique. The phase effect can be explained by interaction of a second‐order distortion productf2−f1and a third‐order distortion product2f1−f2of approximately equal intensities. The intensity relative to the primary tones of both distortion products is influenced strongly by frequency of the primary tones and weakly by intensity of the primary tones.

ISSN:0001-4966    

DOI:10.1121/1.1913046

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

Effects of relative phase on subjective quality were found for signals with two components having a frequency ratio of 1:2 (octave). The data were analyzed by means ofINDSCAL, a multidimensional scaling program. The subjective space corresponding to different phase conditions is a circle, and equal phase differences correspond to equal distances along the circle. These results confirm the sensitivity of the auditory system to waveform even when only two frequency components are involved, and they demonstrate that perception of the two‐component signal falls into an orderly pattern.

ISSN:0001-4966    

DOI:10.1121/1.1913047

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

Although there are some indications of the possible role of lateral inhibition in hearing, there has been no clear demonstration of it in psychophysical experiments. Either the phenomenon plays only a minor role, or it has escaped psychophysical verification. Accepting for a moment the second possibility, is argued in this paper that the threshold of a test tone presentedsimultaneouslywith a masker does not reflect clear lateral‐inhibition effects since the inhibition affectsboththe test tone and the masker. Two different methods, in which the test tone and the masker were presentedsuccsesively, give clear psychophysical evidence of lateral inhibition in hearing. Firstly, the threshold curve of short test‐tone bursts presented in the gaps between repeated masker bursts (noise with a steep negative or positive gradient at a particular frequency) shows marked edge effects. Secondly, the results of psychophysical measurements on two‐tone suppression indicate that the nervous activity due to one frequency component may be suppressed by another component. The effect at the edges of the frequency spectrum are comparable with visual Mach bands, and the interaction of two tones is suggestive of the two‐tone inhibition found in auditory‐nerve fibers.

ISSN:0001-4966    

DOI:10.1121/1.1913048

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

A hybrid‐computer simulation of the Peterson‐Bogert model of the cochlea is reported. The present simulation is shown to be a good representation of the original model except near 10 kHz. The output of the model at one point has many similarities to recent experimental data. In particular, the low‐frequency slope of the amplitude function is +6 dB/oct and the high‐frequency slope is steeply negative. The phase function shows a break from linearity near the resonance frequency and approaches +90° at low frequencies. Quantitative discrepancies between model and experimental data exist, but they could be appreciably reduced by changes in parameter values. Incorporating nonlinear membrane damping in the simulation produces nonlinear effects similar to those observed in the cochlea. With increasing intensity, the displacement peak becomes relatively reduced and occurs at a somewhat lower frequency.

ISSN:0001-4966    

DOI:10.1121/1.1913049

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

The vibratory characteristics of the cat's tympanic membrane (TM) were studied in fresh cadavers and living animals with the aid of time‐averaged holography. Initially, technical difficulties were presented by the TM's small size, low stiffness, and its transparency. Time‐averaged holograms of the TM were obtained for various sound‐pressure levels at a number of frequencies between 600 and 6000 Hz. Reconstructions of such holograms show an image of the TM superimposed by isoamplitude contour lines giving the absolute displacement amplitude at any point on the TM. Vibratory patterns remain essentially unchanged in their first mode up to a frequency of 2000 Hz, with higher modes occurring above that value. At all frequencies, the TM vibrates maximally in the posterior‐superior quadrant and less in the anterior and inferior ones. These results show that, even in its first mode of operation, i.e., below 2000 Hz, the TM does not vibrate like a stiff plate as observed by von Békésy in human cadavers. Rather, the present findings support the curved‐membrane concept of Helmholtz. Contributions to the total transformer action of the middle ear by the area ratio: TM/stapes footplate, the ossicular lever ratio, and that due to the curved membrane action are reevaluated.

ISSN:0001-4966    

DOI:10.1121/1.1913050

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP

摘要:

The detection of a 5‐msec tonal signal presented at various delays after the onset of a 500‐msec tonal masker was investigated in several transient‐masking experiments. Changes in the amount of masking were measured as a function of the delay between onset of the signal and the onset of the longer‐duration masker. In agreement with previous investigations of transient masking there was a large decrease in masked threshold, 26 dB in some conditions, with an increase in signal delay. A “transient overshoot” at masker termination was also noted. These data are consistent with a short‐time energy‐sensing model of detection. In a second transient‐masking study, the masking produced by a gated sinusoid in the presence of a continuous tonal pedestal was investigated. The pedestal results indicate that a simple, linear, time‐invariant, energy‐detection scheme cannot account for the results of two‐tone masking experiments.

ISSN:0001-4966    

DOI:10.1121/1.1913051

出版商:Acoustical Society of America    

年代:1972

数据来源: AIP