Night Vision Current Research and Future Directions, Symposium Proceedings (1987) / Chapter Skim
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Symposium Overview: Three Perspectives
Symposium Overview: Three Perspectives
Pages 303-318
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From page 305... ...
Use of these new anatomical techniques in combination with current electrophysiological techniques and use of 2-deoxyglucose, which allows inentif ication of entire sets of st~mulated or otherwise active neurons, have 9 iven a new meaning to the concept of functional neuroanatomy. The proliferation of identified and putative neurotransir,itters (ana modulators, along with new methods for studying them, has created an 305
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From page 306... ...
Development of the microelectrode since the 1950s has, of course, t rans formed neurophysiology, and to stain and identify impaled cells after recording is now routine. Recent introduction of suction and patch electrodes to investigations of the physiology of photoreceptors and other retinal cells has permitted, in a short tune, precise answers to questions that had defied even approximate answers for a century.
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From page 307... ...
. Laboratory computers have facilitated the use of these techniques and have permitted the efficient choice of the stimulus for each trial from the previously gathered information.- Combined tests of identification with detection have enhanced the power of inferences about underlying mechanisms, and a recent issue of the Journal of the Optical Societv of America (2(9)
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From page 308... ...
The first goal requires personnel that are trained and experienced in human factors, and the equipment would depend on the results of the initial steps of the program. The second goal requires personnel that are trained and experienced in visual psychophysics.
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From page 309... ...
In conclud ing any comments on the laboratory, I draw attention to the f act that answer s to many questions about vision depend on the visual ecology of the observer. In most practical situations, little is known about the visual environment.
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From page 310... ...
o Ad just the magnif ication to put the important spat ial frequencies into the range of S-10 cpd, to which the eye is most sens i t ive . o Reduce intrinsic noise in the visual system -one source of such noise evidently arises from a dark-adapted eye (Makous et al., 1976; Auerbach and Peachey, 1984~; hence, there may be some benefit in light adapting one eye (to remove its contribution of noise)
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From page 311... ...
According to theory, it only helps individuals with a deficit of vitamin A How many individuals have such def icits is, perhaps, an open question, but it seems unlikely that there are many; Dowling and Wald (1960} found that simply depriving rats of vitamin A was not sufficient to produce noticeable effects on their vision -- the animals had to be depr ivea f rom birth.
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From page 312... ...
1978 On the detective quantum eff iciency of the human eye. Vision Research 18 :257-267.
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From page 313... ...
Alfred Owens, describing his dark focus research, also did not specif y what light levels th is dark focus involves and whether it changes with levels of light. For an operational problem, these types of data are very important.
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From page 314... ...
They provide a method to determine: You can go or not go. You have sufficient light vision to begin or you do not have it.
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From page 315... ...
We had a lot of good information presented here that the U.S. Air Force School of Aerospace Medicine can use to help solve operational problems.
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From page 316... ...
In 1982, when I was appointed Chief of the Vision Sciences Division at the Naval Aerospace Medical Research Laboratory, we were tasked with two major work units: Improving Air Combat Performance and Performance8ased Biomedical Standards. The questions presented in both of these units were very difficult to address.
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From page 317... ...
Were are data available through the Air Force that indicate that we do have some data in actual f light scenar ios for quantifying that environment. PHOTORECEPTOR PROPERTIES - Regarding David Copenhagen's comment about the stability of rhodopsin permitting us to see at low light levels, is it possible that we can control this?
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From page 318... ...
Lewis Harvey described the importance of contrast sensitivity and/or edge detection. Contrast sensitivity may have applicability in a more manageable format.
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