title: Proximal-distal, not medial-lateral, movement across an edge increases discrimination of edge sharpness.
abstract: Edges are fundamental properties of our environment and the objects we interact with. There is a lack of research on the haptic perception of edges, especially the sharpness of an edge. Skinner et al. [2013 PLoS ONE, 8(9): e73283] found that haptic discriminability of sharpness was clearly superior when using a relatively unrestrained, free exploration strategy compared with a static single touch strategy. In the free exploration condition two distinct movement patterns were frequently used by participants: a proximal-distal movement of the fingerpad across the test edge and a medial-lateral movement of the fingerpad along the test edge. Here, using the same stimuli and two-alternative forced-choice method of constant stimuli as Skinner et al. (2013), we demonstrate that a proximal-distal movement results in substantially lower sharpness discrimination thresholds than a medial-lateral movement. The underlying neurophysiology and implications for the design of haptic displays are considered.
authors.forename: Christopher
authors.initials: C
authors.lastname: Kent
authors.forename: Andy L
authors.initials: AL
authors.lastname: Skinner
authors.forename: Carys
authors.initials: C
authors.lastname: Weeds
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Benton
mesh_terms: D000328:Adult; D004192:Discrimination, Psychological / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008465:Mechanoreceptors / Q000502:physiology; D009068:Movement / Q000502:physiology*; D013334:Students / Q000523:psychology; D055698:Touch Perception / Q000502:physiology*; D055815:Young Adult