Visual Sensitivities and Discriminations and Their Role in Aviation
Abstract
Study results include: 1) Selective 'blindness' to approaching or receding motion in depth exists and seems to be not uncommon in normally-sighted individuals. Of 16 subjects, 8 had visual field defects for either approaching or receding motion. Of 21 subjects, only 6 had full symmetric fields for oscillatory motion in depth. Visual sensitivity to sideways motion was normal in stereomotion-blind areas. 2) A perfectly camouflaged bar within a random dot pattern was rendered visible by moving dots within the bar and outside the bar with equal and opposite velocities (motion parallax). The bar's orientation could be judged with equal precision (0.5 deg) to that of an uncamouflaged dotted bar made visible by brightness contrast providing that dot speed and contrast were high. When contrast was reduced, discrimination collapsed for the camouflaged bar earlier than for the uncamouflaged bar. This suggests that helicopter pilots may risk making visual judgment errors in nap-of-the-earth flight where some objects and ground features are seen by motion alone. 3) Data collection is complete on measuring shape discrimination of camouflaged objects. 4) We have developed a new mathematical approach to testing multi-neuron models in which individual neurons are modelled as rectifiers. 5) We have developed a nondestructive zoom-FET technique that allows spectra of EEG and other time series to be computed with the theoretical resolution allowed by the Heisenberg- Gabor relation, e.g. 50,000 lines DC-100 Hz at a resolution of 0.002 Hz from a 500-sec recording. Keywords: Binocular vision; Visual flying skills; Visual assessment; Motion perception; Evoked potentials; Neuromagnetic recording; Nonlinear analysis. Canada.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 30, 1987
- Accession Number
- ADA204771
Entities
People
- David Regan
Organizations
- University of York