Article Simultaneous Sketching Aids the Haptic Identification of Raised Line Drawings S. Cecchetto and R. Lawson Department of Experimental Psychology, University of Liverpool, UK Abstract Haptically identifying raised line drawings is difficult. We investigated whether a major component of this difficulty lies in acquiring, integrating, and maintaining shape information from touch. Wijntjes, van Lienen, Verstijnen, and Kappers reported that drawings which participants had failed to identify by touch alone could often subsequently be named if they were sketched. Thus, people sometimes needed to externalize haptically acquired information by making a sketch in order to be able to use it. We extended Wijntjes et al.’s task and found that sketching while touching improved drawing identification even more than sketching after touching, but only if people could see their sketches. Our results suggest that the slow, serial nature of information acquisition seriously hampers the haptic identification of raised line drawings relative to visually identifying line drawings. Simultaneous sketching may aid identification by reducing the burden on working memory and by helping to guide haptic exploration. This conclusion is consistent with the finding reported by Lawson and Bracken that 3-D objects are much easier to identify haptically than raised line drawings since, unlike for vision, simultaneously extracting global shape information is much easier haptically for 3-D stimuli than for line drawings. Keywords Haptic, object, touch, picture, externalization Have you ever tried to use your hand like a scanner? Probably not, but if you try it, you will discover that your fingers are easily able to identify familiar 3-D objects in the absence of vision. Klatzky, Lederman, and Metzger (1985) showed that people are both fast (often taking under 2 s) and accurate at naming everyday objects using haptics (active touch). In contrast, it is well-established that both sighted and congenitally blind people find it difficult to identify raised line drawings using touch alone (e.g., Heller, 1989; Heller, Calcaterra, Burson, & Tyler, 1996; Kennedy & Bai, 2002; Klatzky, Loomis, Lederman, Corresponding author: R. Lawson, Department of Experimental Psychology, University of Liverpool, Eleanor Rathbone Building, Bedford Street South, Liverpool L69 7ZA, UK. Email: rlawson@liverpool.ac.uk Perception 2015, Vol. 44(7) 743–754 ! The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0301006615594695 pec.sagepub.com