[The resolution and discrimination of images in the visual system].
We analysed the conformity of optic and retinal cones anatomy factors by the two-point test. Obtained by F. Campbell and R. W. Gubish, the point spread function has a width of about 1 arc min. Cones sizes are equal to 0.5 arc min in the fovea. Functional pixel consists of 3-5 cones under the point spread function. Such an organisation in very useful in decreasing the samping noise of receptors. We carried out psychophysical investigations to show a consensus among the optic, receptors', and neuronal levels. In experiments we studied changes of the two-point pattern perception in respect to the points separation, measured the orientation threshold of small size stimuli. Data were compared with optical point-spread function, the hexagonal mosaic of cones, and line spread function of spatial elements, which form spatial frequency channels at the cortical level.
Shelepin
Iu E
IuE
I. P. Pavlov Institute of Physiology, Russian Acad. Sci., St. Petersburg, 199034, Nab. Makarova, 6, Russia.
Bondarko
V M
VM
D000221:Adaptation, Ocular / Q000502:physiology; D000328:Adult; D000368:Aged; D015350:Contrast Sensitivity / Q000502:physiology*; D004192:Discrimination, Psychological / Q000502:physiology*; D005584:Fovea Centralis / Q000502:physiology; D006801:Humans; D008875:Middle Aged; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation; D010786:Photoreceptor Cells / Q000502:physiology; D011601:Psychophysics