Results 291 to 300 of about 3,335,604 (350)

Behavioral estimates of absolute threshold in rat

Visual Neuroscience, 1994
AbstractDark-adapted thresholds of albino and pigmented rats were estimated using behavioral methods. Albino and pigmented rats who had been water deprived learned to bar press for water reinforcement when a light stimulus was presented. Absolute threshold was defined to be the light intensity at which bar pressing behavior was significantly modified ...
C, Muñoz Tedó, P, Herreros de Tejada, D G, Green   +2 more
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Absolute Threshold and Frequency-of-Seeing Curves

Journal of the Optical Society of America, 1955
The simplest interpretation of the uncertainty of seeing observed at the absolute threshold is based on the theory of quantum fluctuations and assumes that in any given trial the light is seen when the retina has been acted upon by at least n quanta. When this assumption is true the frequency-of-seeing curve is a simple Poisson sum of parameter n, and ...
M H, PIRENNE, F H, MARRIOTT
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Human binocular summation at absolute threshold

Vision Research, 1974
Abstract Psychophysical data are presented which indicate that the neural inputs of two stimuli presented simultaneously to corresponding retinal areas summate physiologically to lower the binocular absolute threshold. This binocular summation is not present when the stimuli are separated by more than 100 msec or are delivered to noncorresponding ...
F, Thorn, R M, Boynton
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Inadequacies of absolute threshold levels for diagnosing prediabetes

Diabetes/Metabolism Research and Reviews, 2010
AbstractPrediabetes comprising Impaired Fasting Glucose (IFG) and Impaired Glucose Tolerance (IGT) represents an intermediate stage of altered glucose metabolism between normal glucose levels and type 2 diabetes mellitus and is associated with an increased risk for the development of diabetes and cardiovascular disease.
M. Bergman
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Absolute Threshold Conditions for Visual Perception

Journal of the Optical Society of America, 1955
A quantitative approach to an understanding of fluctuating phenomena encountered near the threshold of vision has involved an analysis of frequency of seeing curves. The results of various investigators are discussed with reference to the possibility of an explanation based exclusively on the statistical fluctuations in the stimulating energy ...
M. A. Bouman
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Auditory reaction time and absolute threshold in cat

The Journal of the Acoustical Society of America, 1977
Reaction time and absolute thresholds for acoustic stimuli were measured in cats using an operant reaction-time procedure in conjunction with titration methodology. The reaction-time/titration procedure incorporated a self-paced feature and utilized a photobeam operandum developed for the cat.
G M, Gerken, D, Sandlin
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Binocular Summation at the Absolute Threshold of Peripheral Vision*

Journal of the Optical Society of America, 1962
Binocular probability of seeing, P(B), was measured as a function of the time between onsets of 2-msec, 35-min visual angle flashes to corresponding locations 7° horizontally displaced from the foveas of both eyes of dark-adapted subjects. P(B) was greater than the value that would be predicted if the two eyes were independent detectors [P′(B)] for ...
L. Matin
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Summation of rod and cone responses at absolute threshold

Vision Research, 1982
Visual thresholds were measured for rod stimuli, cone stimuli and mixtures of rod and cone stimuli. Comparisons of the rod and cone thresholds to the corresponding components of the mixed-stimulus thresholds revealed summation between subthreshold rod and cone responses.
B. Drum
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Absolute auditory threshold: testing the absolute

European Journal of Neuroscience, 2017
AbstractThe mechanisms underlying the detection of sounds in quiet, one of the simplest tasks for auditory systems, are debated. Several models proposed to explain the threshold for sounds in quiet and its dependence on sound parameters include a minimum sound intensity (‘hard threshold’), below which sound has no effect on the ear.
Peter Heil, Artur Matysiak
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Absolute Thresholds and Night Myopia

Journal of the Optical Society of America, 1949
The first measurements of night myopia showed a clear decrease in the minimum quantity of light needed to reach a certain visual acuity when the night myopia was compensated. The results indicated a possible decrease in absolute thresholds. In the present paper we study, with four observers using binocular vision and white light, the influence of night
J M, OTERO, L, PLAZA, F, SALAVERRI
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