The effect of blur and contrast of VEP latency: comparison between check and sinusoidal grating patterns

doi:10.1016/0168-5597(87)90045-1

Electroencephalography and Clinical Neurophysiology/Evoked Potentials Section

Volume 68, Issue 4, July 1987, Pages 247-255

https://doi.org/10.1016/0168-5597(87)90045-1 Get rights and content

Abstract

Pattern defocusing was used to evaluate the contribution of different spatial frequency components in checks to VEP latency. Latency shifts with increasing blur (−2.5 to +2.5 diopters) were determined for sinusoidal grating and check patterns equated in fundamental spatial frequency. With both check and grating patterns, the effect of blur was greater the higher the spatial frequency. Given an equal fundamental spatial frequency, however, the latency of checks was more effected. This latency difference between check and sine patterns was pronounced at low fundamental spatial frequencies(large pattern) and decreased with higher spatial frequencies (small pattern). Latencies were then compared for patterns which were defocused vs. simply reduced in contrast. Results show that the increase in latency with defocused large checks is due to both fundamental and higher harmonic spatial components but with small checks, to the fundamental spatial frequency aeone.

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¹: Present address: Department of Ophthalmology, University of Illinois at Chicago, Chicago, IL 60612, U.S.A.

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Main articleThe effect of blur and contrast of VEP latency: comparison between check and sinusoidal grating patterns

Abstract

Vision Res.

Electroenceph. clin. Neurophysiol.

Vision Res.

Vision Res.

Vision Res.

Vision Res.

Vision Res.

Vision Res.

Vision Res.

Vision Res.

Comparison of contrast thresholds of large bars and checks measured by VECPs and psychophysically as a function of defocusing

Albrecht v. Graefes Arch. Ophthal.

On the separability of two mechanism involved in the detection of grating patterns in humans

J. Physiol. (Lond.)

The effect of stimulus orientation on the visual evoked potential in multiple sclerosis

Ann. Neurol.

Main article
The effect of blur and contrast of VEP latency: comparison between check and sinusoidal grating patterns