Binocular and monocular relations in foveal dark adaptation.

Cook, Thomas W.

doi:10.1037/h0093353

Cited by 14 publications

(10 citation statements)

References 27 publications

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“…[Two notable exceptions are the experiments by Cook (1934) and Downey (I 919), both of whom used the time required from onset of dark adaptation to detect a dim light as the measure of threshold: the former found evidence for summation in the fovea, while the latter failed to find such evidence.] Typically, the percent-correct estimate has been obtained with a method of constant brightness, i.e., a briefly presented target of fixed intensity, whereas the minimum intensity threshold has been obtained by some form of the method of limits, i.e., a systematic increase and/or decrease in the luminance of a target of duration sufficient to be easily seen at higher luminances.…”

Section: Methods Ofstimulus Presentationmentioning

confidence: 95%

“…This issue was not completely resolved until a convincing demonstration of foveal adaptation by Hecht (1921) revealed that the time course of dark adaptation in the fovea was extremely rapid, with the most sensitive state assumed after only a few minutes. This rmding led Cook (1934) to reconsider the issue of foveal summation, since the previous experiments concerning foveal summation (i.e., those by Abney and Watson and by Graham) had measured thresholds only after 30 min of dark adaptation. In a carefully designed experiment, Cook measured foveal threshold for left, right, and both eyes at stages of dark adaptation ranging from a few seconds to nearly an hour.…”

Section: Binocular Summanon At Thresholdmentioning

confidence: 99%

“…Several workers (Cook, 1934;Graham, 1931;Hecht, 1921) questioned Piper's convention of plotting the reciprocal of threshold intensity as a measure of sensitivity, asserting that such a convention made the unwarranted assumption that the threshold is the inverse of sensitivity. Cook argued that the shape of the sensitivity curves was due to mathematical properties peculiar to a series of reciprocals rather than to basic visual processes.…”

Section: Binocular Summanon At Thresholdmentioning

confidence: 99%

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The psychophysical inquiry into binocular summation

Blake

Fox

1973

Perception & Psychophysics

282

163

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Experiments that compare monocular and binocular visual performance of human psychophysical Os on a variety of visual tasks are reviewed, The review attempts to include all experiments published in English in this century, excluding work on stereopsis, rivalry, and evoked potentials, The concept of probability summation as a baseline for assessing the presence of neural summation is discussed, and the assumptions of several models for estimating probability summation are considered. Experiments are classified in terms of visual task, major categories being increment detection, flicker fusion, brightness magnitude, and contour resolution. A major conclusion is that binocular performance is superior for essentially all task categories and in most cases by a magnitude greater than that predicted by appropriate probability summation models.The cardinal feature of the binocular visual system in man is the unification of the two separate monocular views into a binocular cyclopean view that betrays little trace of its monocular origins. Relatively little is known about the mechanism responsible for unification, although an examination of the physiology of the visual system reveals a number of features that seem expressly designed to promote unification. Some of the more prominent features are the partial crossing of the optic tracts at the optic chiasma and the elaborate system for the maintenance of conjugate eye movements. The existence of these features in man, and in binocular vertebrates in general, suggests an adaptive function of binocularity of sufficient magnitude to justify the survival of this complicated physiological organization. Yet the immediate advantage of having two eyes functioning as one is not obvious. The simple experiment of closing one eye does not result in any dramatic change in the appearance of the visual world. Rather, only by more stringent experimentation are the subtle advantages of binocularly joined eyes revealed.The purpose of this paper is to review those experiments undertaken in the 20th century that have compared monocular and binocular performance on a variety of visual tasks. The rubric under which such experiments are typically grouped is "binocular summation." These experiments compare the relative performance on some visual task (such as detection or form resolution) by a human S using one and both eyes. In the literature, this kind of inquiry into binocular vision is treated separately from investigations of stereopsis and of binocular rivalry; following that distinction, the voluminous research on these binocular phenomena is not included. A further exclusion is data

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Section: Methods Ofstimulus Presentationmentioning

confidence: 95%

Section: Binocular Summanon At Thresholdmentioning

confidence: 99%

Section: Binocular Summanon At Thresholdmentioning

confidence: 99%

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The psychophysical inquiry into binocular summation

Blake

Fox

1973

Perception & Psychophysics

282

163

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“…For peripheral dark adaptation it has been found that variations in preadaptation exposure modify such features of the dark adaptation curve as the initial threshold value, the slope of the curve, the time of the cone-rod transition point, and the time course of adaptation. In his experiment, Cook (2) found that varying the duration of preexposure changed the course of foveal dark adaptation: following 3 minutes' preexposure the initial threshold value was higher and the slope of the curve was not as steep as after 1 minute's preexposure. Crawford (3) investigated the effect of preexposure duration and intensity upon foveal dark adaptation for a wide range of intensities and durations.…”

Section: Introductionmentioning

confidence: 99%

The Effect of Varying the Intensity and the Duration of Preexposure Upon Foveal Dark Adaptation in the Human Eye

Mote

Riopelle

1951

Journal of General Physiology

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The course of foveal dark adaptation was studied as a function of the intensity and duration of preexposure. Four intensities (11,300, 5,650, 1,130, and 565 mL.) and four durations (300, 150, 30, and 15 seconds) were used in all combinations of intensity and duration. The threshold-measuring instrument was a monocular Hecht-Shlaer adaptometer and the threshold measurements were recorded in log micromicrolamberts. There were two subjects and each went through the complete series of intensities and durations five times. The five logarithmic values obtained for each threshold were converted into a geometric mean and these means were the data used in the analysis of the results. The chief results were as follows:— 1. For each subject the final steady threshold value was in the region of 7.0 log µµL. 2. As the intensity, or duration, or both, were increased the initial foveal dark adaptation threshold rose, the slope of the curve decreased, and the time to reach a final steady threshold value increased. 3. For those values of preexposure intensity and time for which the product, I x t, is a constant it was found that for the two higher intensities and two longer durations and also for the two lower intensities and two shorter durations, the dark adaptation curves were the same. For other values of I x t = C the curves were generally not the same.

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“…It might be appropriate to refer briefly to the problem of binocular summation before going directly into the description of the experiments. Binocular summation has been repeatedly studied by comparing, under monocular and binocular conditions, stimulus limens for brightness (Cook , 1934;Collier, 1954;Collier & Kubzansky, 1958;Graham, 1930;Graham, 1931;Shaad, 1935), supra-liminal brightnesses (De Silva & Bartley, 1930;Liebowitz & Walker, 1956) and critical fusion frequencies (Ire-]and, 1950;Perrin, 1954). However, under what condition and to what extent the summation takes place are still in controversy**.…”

Section: Tarow Indow and Takaaki Koyazu Keio Universitymentioning

confidence: 99%

Experiments on Induction in the Binocular Fields Composed of the Independent Monocular Fields (2)

Indow

Koyazu

1961

Jpn. Psychol. Res

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for his continuing interest throughout the series of investigations. Thanks are due to S. Horiuchi for his collaboration as E, also to T. Kozaki, S. Tominaga, and K. Watanabe as Ss in some parts of experiments. This study was financed by the Ministry of Education. * *References are limited only to the articles that the authors had the opportunity to read through personally. Experiments on Induction•@ 43

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Binocular and monocular relations in foveal dark adaptation.

Cited by 14 publications

References 27 publications

The psychophysical inquiry into binocular summation

The psychophysical inquiry into binocular summation

The Effect of Varying the Intensity and the Duration of Preexposure Upon Foveal Dark Adaptation in the Human Eye

Experiments on Induction in the Binocular Fields Composed of the Independent Monocular Fields (2)

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