“…The sensitivity to large-field motion patterns resembling optic flow in the dorsal portion of MST (MSTd) supports the view that MST is involved in self-motion perception (Saito et al, 1986;Tanaka et al, 1986Ungerleider and Desimone, 1986;Komatsu and Wurtz, 1988;Duff y andWurtz, 1991a,b, 1995;Orban et al, 1992;Lagae et al, 1994;Bradley et al, 1996;Lappe et al, 1996). Neurons that respond preferentially to expansion could convey information about forward translation (Saito et al, 1986;Tanaka et al, 1986Perrone, 1987Perrone, , 1990Glünder, 1990;Hatsopoulos and Warren, 1991), and this principle can be generalized to combined translation and rotation (Perrone, 1992;Perrone and Stone, 1994). However, because many MST neurons show a form of "position invariance," i.e., they prefer a specific type of motion (e.g., counterclockwise rotation) regardless of where in their receptive field that motion is presented (Duffy and Wurtz, 1991b;Orban et al, 1992;Graziano et al, 1994;Lagae et al, 1994), MST seemed ill-suited to support navigation.…”