Meeting Abstract
Deft coordination of body movement in animals exploits the capabilities of the level of synergies, a level orchestrated through haptic perception. Here, my goal is to exemplify how animals’ attunement to perceptual invariants underlies haptic perception in motor control. Fourteen participants wielded twelve different occluded objects held in air or immersed in water and reported their perceived lengths. Each object consisted of a rod of specific density with specific number of stacked steel rings attached at a specific location along its length. A single-valued function of the rotational inertia, I —an invariant mechanical property—predicted their perceived lengths in both air and water, and the perceived lengths remained invariant across the two media. It is known that lowering muscle temperature slows the development and transmission of muscular force and diminishes muscle stretch-reflex sensitivity. I hypothesized that if the haptic information acquired during perception through dynamic touch is derived from muscle activity, changes in mechanical properties of muscles should result in altered magnitudes of haptic stimulation. Twelve participants wielded the occluded objects and reported their perceived lengths at three different muscle temperatures. The perceived lengths of the objects were longer and the relationship between I and the perceived lengths was stronger at a higher muscle temperature. My results imply a direct and reciprocal relationship between action and perception arbitrated through smart perceptual devices attuned to extract perceptual invariants from their environment. I discuss how the concept of perceptual invariants provides a principled approach to haptic perception in motor control, at land, in water, in air, and in space, of a fish’s fin, a flamingo’s neck, a monkey’s tail, a snake’s spine, and a bat’s wing.
