scispace - formally typeset
Search or ask a question
Topic

Absolute threshold

About: Absolute threshold is a research topic. Over the lifetime, 415 publications have been published within this topic receiving 13867 citations.


Papers
More filters
Journal Article
TL;DR: In this paper, a model for steady sounds is described having the following stages: 1) a fixed filter representing transfer through the outer ear, 2) an excitation pattern from the physical spectrum, 3) transformation of the excitation patterns to a specific loudness pattern, 4) determination of the area under the specific loudeness pattern, 5) determination for a given ear, and 6) summation of loudness across ears.
Abstract: A loudness model for steady sounds is described having the following stages: 1) a fixed filter representing transfer through the outer ear; 2) a fixed filter representing transfer through the middle ear; 3) calculation of an excitation pattern from the physical spectrum; 4) transformation of the excitation pattern to a specific loudness pattern; 5) determination of the area under the specific loudness pattern, which gives overall loudness for a given ear; and 6) summation of loudness across ears. The model differs from earlier models in the following areas: 1) the assumed transfer function for the outer and middle ear; 2) the way that excitation patterns are calculated; 3) the way that specific loudness is related to excitation for sounds in quiet and in noise; and (4) the way that binaural loudness is calculated from monaural loudness. The model is based on the assumption that sounds at absolute threshold have a small but finite loudness. This loudness is constant regardless of frequency and spectral content. It is also assumed that a sound at masked threshold has the same loudness as a sound at absolute threshold. The model accounts well for recent measures of equal-loudness contours, which differ from earlier measures because of improved control over bias effects. The model correctly predicts the relation between monaural and binaural threshold and loudness. It also correctly accounts for the threshold and loudness of complex sounds as a function of bandwidth.

793 citations

Journal ArticleDOI
TL;DR: The method of magnitude estimation was used to investigate how the level of adaptation affects the power function relating brightness to luminance, and the results are described by the equation ψ=k(L−L0)β, when ψ is brightness, L luminance and L0 the absolute threshold.
Abstract: The method of magnitude estimation was used to investigate how the level of adaptation affects the power function relating brightness to luminance. With the left eye dark adapted and the right eye light adapted, a test field was presented briefly to one eye. The observers’ estimates generated a pair of brightness functions, one for each eye. The validity of these functions was checked by interocular brightness matching. The results are described by the equation ψ=k(L−L0)β, when ψ is brightness, L luminance, and L0 the absolute threshold. All the parameters—k, L0, and β—change systematically with light adaptation. The exponent β increases from 0.33 for the dark-adapted eye to 0.44 for the eye adapted to 1 lambert.

482 citations

Journal ArticleDOI
TL;DR: The hypothesis that noise in the optic pathway limits its sensitivity is formulated quantitatively, and shown to be able to account for the above experiment, and also the disagreement in the literature between those who believe that the absorption of two quanta can cause a sensation, and thosewho believe that 5 or more are required.
Abstract: It is shown that the absorption of one quantum can excite a rod in the human retina, but that at least two, and probably many more, excited rods are needed to give a sensation of light. It is suggested that noise in the optic pathway limits its sensitivity, and this idea is subjected to an experimental test. The hypothesis is then formulated quantitatively, and shown to be able to account for the above experiment, and also the disagreement in the literature between those who believe that the absorption of two quanta can cause a sensation, and those who believe that 5 or more are required. The formulation of the hypothesis is used to calculate the maximum allowable noise (expressed as a number x of random, independent events confusable with the absorption of a quantum of light) in the optic pathway for the absorption of various fractions of the total number of quanta incident at the cornea.

424 citations

Journal ArticleDOI
TL;DR: It seems reasonable to conclude that responses to mechanical displacement of the skin are mediated by more than one receptor system, although direct evidence is still lacking.
Abstract: Vibrotactile thresholds were determined as a function of frequency, contactor configuration, and contactor area. It was found that contactor area is a more important stimulus parameter than the gradient or curvature of displacement. The absolute threshold for vibration seems to be independent of frequency when very small contactors are used and independent of area at low frequencies. For higher values of these parameters, it strongly depends on both. It seems reasonable to conclude that responses to mechanical displacement of the skin are mediated by more than one receptor system, although direct evidence is still lacking.

378 citations

Journal ArticleDOI
TL;DR: A loudness model that is applicable to both normal and impaired hearing is described, and can account for the loudness recruitment and reduced loudness summation that are typically associated with cochlear hearing loss.

252 citations


Network Information
Related Topics (5)
Stimulus (physiology)
16K papers, 674.4K citations
74% related
Visual perception
20.8K papers, 997.2K citations
72% related
Visual cortex
18.8K papers, 1.2M citations
69% related
Reflex
22.6K papers, 678.6K citations
67% related
Membrane potential
18.7K papers, 939.6K citations
66% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20223
20214
20202
20194
20186
20175