Jean Piaget was a developmental psychologist - c. Piaget was infact one of the most known developmental psychologists which are very important and have been very important for the development of developmental psychology. He has had tremendous impact on the different fields within psychology and out of it.
Brightness is an attribute of visual perception in which a source appears to be radiating or reflecting light.In other words, brightness is the perception elicited by the luminance of a visual target. This is a subjective attribute/property of an object being observed and one of the color appearance parameters of color appearance models.
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