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Science 5 April 1968:
Vol. 160. no. 3823, pp. 21 - 28
DOI: 10.1126/science.160.3823.21

Articles

Flicker Fusion Phenomena

Rapid flicker is attenuated many times over by repeated temporal summation before it is "seen."

John Z. Levinson 1

1 The Technical Staff at Bell Telephone Laboratories, Murray Hill, New Jersey

The high-frequency temporal behavior of the human visual system has been shown to have some of the properties of a linear low-pass filter. For such a system it is appropriate to consider a repetitive stimulus as having separable Fourier harmonic components. The direct-current component or average luminance is important in that it sets the adaptation level. It is therefore convenient to keep it constant when varying other stimulus parameters, such as frequency or wave form. Of the alternating-current components, only the fundamental is important at high frequencies, the higher harmonics being relatively more attenuated.

Any linear low-pass filter system responds in a predictable way to sinusoidal stimulation, whether continuous or of short duration. In the case of the visual system, predictable behavior is found at high frequencies, and it leads to discovery of hitherto unobserved pseudoflash and real flash phenomena. Measurement of a new characteristic time is suggested.

At low frequencies the use of half and whole-sinusoidal flashes leads to the discovery of some interesting relations with flicker thresholds, but these remain for future discussion.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Intrasaccadic Perception.
M. A. Garcia-Perez and E. Peli (2001)
J. Neurosci. 21, 7313-7322
   Abstract »    Full Text »    PDF »
Visual Transient Phenomenon: Its Polarity and a Paradox.
J. F. Bird and G. H. Mowbray (1969)
Science 165, 588-589
   Abstract »    PDF »



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