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Scotopic And Photopic Thresholds : A Dependent Variable For The Mccollough Effect, Marilyn Murphy

Dissertations and Theses

Previous attempts to adequately evaluate orientation-specific colored aftereffects (Mccollough Effects) have thus far been unsuccessful in yielding quantitative measures of relative strengths of the effects. Similarly, little success has been shown in previous attempts to establish what level of illumination is necessary in order to evoke the aftereffects. The present study sought to determine (a) whether threshold measurements could serve as adequate, quantitative dependent variables of the Mccollough Effects, (b) whether photopic illumination was necessary in order to evoke the aftereffect. It was predicted that the greater the number of inspection trials, the dimmer the illumination level could be in …