“…Other experiments have demonstrated that observers can recognize their own egomotion (Lee & Aronson, 1974;Lee & Lishman, 1975;Lishman & Lee, 1973;Warren, 1976) or the translation in depth of external objects (Borjesson & von Hofsten, 1972, 1973Johansson, 1950Johansson, , 1964Schiff, 1965). There is also evidence that observers can recognize more complicated rigid motions such as rotation about an axis that is translating (Duncker, 1929(Duncker, /1937Johansson, 1964Johansson, , 1973Johansson, , 1974aProffitt, Cutting, & Stier, 1979) or rotating (Johansson, 1958(Johansson, , 1974bRubin, 1927).…”