As easy to move as a feather: perception of lightness as ease to move.

When perception by touch is couched in terms of movement, perception of heaviness can be understood as perception of difficulty to move. This experiment further investigated this proposal as well as the corollary proposal that perception of lightness may be understood as perception of ease to move. Blindfolded participants wielded weighted objects and rated how heavy or light each object felt and how difficult or easy each object was to move. Ratings of heaviness and difficulty to move were analogously constrained by movement-relevant variables. Ratings of lightness and ease-to-move were also analogously constrained by such variables, but in the opposite manner. Conventional descriptors such as heaviness or lightness may be inappropriate for a principled understanding of perception by touch.