Research Note White’s Effect and Assimilation

1. White’s effect in lightness, color and motion

In White’s (1979) illusion of lightness, the background is a square-wave grating of black and white stripes (Fig. 1a). Grey segments that replace parts of the black stripes look much lighter than grey segments that replace parts of the white stripes. Assimilation from flanking stripes has been proposed, the opposite of simultaneous contrast. We use colored patterns to demonstrate that the perce...

Enhanced Predictions of Tides and Surges through Data Assimilation (TECHNICAL NOTE)

The regional waters in Singapore Strait are characterized by complex hydrodynamic phenomena as a result of the combined effect of three large water bodies viz. the South China Sea, the Andaman Sea, and the Java Sea. This leads to anomalies in water levels and generates residual currents. Numerical hydrodynamic models are generally used for predicting water levels in the ocean and seas. But thei...

The Early History of White’s Illusion

The illusion that is now commonly referred to as ‘White’s illusion’ involves changes in the lightness of the mid-grey test elements that replace sections of the black or white bars of a black–white square–wave grating. This paper describes the discovery of White’s illusion; an attempt to explain it in terms of assimilation theory; the interest it has generated amongst vision researchers; the su...

The mechanisms involved in brightness induction effects: a reply to Zaidi.

McCourt (1982) described what he called the “grating induction effect”: an illusory grating is induced in a physically homogeneous grey stripe superimposed upon and orthogonal to a sinewave grating. The induced grating is 180 deg out of phase with, and (at least in the case described above) has the same spatial frequency and orientation as, the inducing grating. Zaidi (1989) has recently descri...

Effect of genotype variability on nitrate uptake and assimilation of barley cultivars