Both hemispheres are equally good at lower-level (first stages) visual processing (e.g., perceiving an illusion where contours are perceived, even though there is no line, luminance, or color change). The right hemisphere, however, is better at a variety of visual tasks that involve advanced processing (e.g., mental rotation of objects, detecting whether two images are identical or mirror reversed, perceptual grouping, and temporal-discrimination tasks). (Gazzaniga, Michael S. Who's in Charge? p 92-93. NY: HarperCollins Publishers, 2011)