Abstract

A summation index σ was originally defined to show the summating effect of two test flashes in determining the increment threshold. The definition was extended here for any number of test flashes and the index was measured for n light flashes that were presented to the eye successively. When the interflash interval was 60 msec, the index showed the inhibition for any number of flashes (n), that is the index value of near zero. At t=40 msec, the index value was about 0.1 for two flashes and it remained about the same as n was increased. At t=120 msec on the other hand, the index gradually increased from 0.1 to 0.2 as n was increased from 2 to 10. It is suggested that these results are reasonably explained assuming a diphasic response for the peripheral visual system corresponding to each light flash, and superposing a number of them linearly with suitable intervals.

© 1966 Optical Society of America

Temporal Summation of Positive and Negative Flashes in the Visual System*

Mitsuo Ikeda
J. Opt. Soc. Am. 55(11) 1527-1534 (1965)

Study of Temporal Visual Response by the Summation Index

Toshio Uetsuki and Mitsuo Ikeda
J. Opt. Soc. Am. 60(3) 377-381 (1970)

Temporal Summation During Backward Visual Masking*

Robert T. Kintz and Robert M. Boynton
J. Opt. Soc. Am. 59(2) 212-216 (1969)

Further Use of the Summation Index for the Study of Color Vision*

Mitsuo Ikeda
J. Opt. Soc. Am. 54(1) 89-94 (1964)

Study of Interrelations between Mechanisms at Threshold*

Mitsuo Ikeda
J. Opt. Soc. Am. 53(11) 1305-1313 (1963)