Saturation is the psychological dimension that captures the purity and vividness of color sensations. Brightness is the dimension of color experiences that captures the intensity of light. Afterimages or aftereffects of visual stimulation may be either positive or negative. Negative afterimages are the opposite or the reverse of the original experience. Positive afterimages are caused by a continuation of the receptor and neural processing following stimulation.
Color blindness is the partial or total inability to distinguish colors.
Check your Recall Hearing The Physics of Sound Amplitude measures the physical strength of the sound wave and relates to loudness. Frequency measures the number of cycles the wave completes in a given amount of time. The loudness, or physical intensity, of sound is determined by its amplitude. Timbre reflects the quality of complexity of the sound wave. The physiology of hearing is involved in four basic energy transformations.