Four pairs of spots rotating around their common centers, each pair a "doublet", were arranged in a square formation. The doublets initially appear to rotate "locally", but then coalesce into two large squares that slide over each other along circular paths ("global" motion). This perceptual transition from local to global motion occurred within and across a series of repeat trials (Experiment ...

Psychophysical evidence is given for the existence of two distinct systems in human vision: a fast, sign-invariant system concerned with extracting contours and a slower, sign-sensitive system concerned with assigning surface color. A class of stimuli we developed seems to selectively activate the fast, contour system. This stimulus is formed by adjacent fields of black and white spots, which f...

In this study we consider the frequency of coat color variation among Yakutsk stray dogs. The was carried out at same time in three city districts: Centralniy, Saysarskiy and Stroitelniy. districts differ urban development population density Stroitelniy Districts belong to a one-two-storey residential type building, Centralniy one multi-storey type. 8 types colors were distinguished: black, whi...

A new subspecies of Lon taxiles (W. H. Edwards, 1861) is described from the Pine Ridge Nebraska and Black Hills South Dakota. It distinguished by presence distinct white spots on VHW females darker males than specimens other parts its range.

In a classic Hermann grid display, faint and transient (illusory) spots are produced at the intersections of a white grid superimposed on a black background (or vice versa). In a variant of the Hermann grid developed by Spillmann and Levine (Spillmann, L., & Levine, J. (1971). Contrast enhancement in a Hermann grid with variable figure-ground ratio. Experimental Brain Research, 13, 547-559), th...

The data on traffic accidents clearly points to "Black Spots" that continually cause a high rate of accidents. However, road safety research is still far from understanding why this particular place on a road is risky. The reason is the deficit of knowledge of how pedestrians and drivers interact when facing a potentially dangerous traffic situation, and in the lack of an integrated framework t...