Introduction

1. Intention Recognition in Autistic Spectrum Condition (ASC) using Video Recordings and their Corresponding Animacy Display. Phil McAleer1, Lawrie McKay1, Judith Piggot2, David R. Simmons1, Frank E. Pollick1 1Department of Psychology, University of Glasgow, 2Cardiff University phil@psy.gla.ac.uk http://paco.psy.gla.ac.uk & www.psy.gla.ac.uk/~phil Introduction • Heider and Simmel (1944) showed that people, on viewing a simple animation involving geometric shapes, would attribute emotions and intentions to the shapes based on their movements. • People with Autistic Spectrum Condition (ASC) are known to be deficient in visualizing the intent of others, especially in “Theory of Mind” tasks involving animacy displays (Castelli, Frith, Happe & Frith, 2002). • Our previous research introduced a new method to create animacy displays directly from human motion, and results showed people attributed higher ratings of animacy to displays showing an overhead perspective (McAleer et al. 2004). • We continue to use this method of stimuli production toinvestigate: (1) the attribution of social intention in people with ASC’s; (2) the effect of viewpoint of the display; (3) compare the judgement of intention in the animacy displays to the corresponding original video displays. Stimulus Production • Design • 6 Intentions: CHASE, FIGHT, FLIRT, FOLLOW, GUARD & PLAY. • 2 Viewpoints: OVERHEAD & SIDE. • Task • 6 ALTERNATIVE FORCED CHOICE. • A pair of actors were filmed on a 3½m square stage using two digital video cameras: one positioned directly above centre stage (Overhead); the second positioned inline with the centre of the side of the stage (SideView). The actors performed the following six intentions: Chase, Fight, Flirt, Follow, Guard & Play (Blythe, Todd & Miller, 1999). • The X and Y co-ordinates were extracted from the footage using the EyesWeb open platform for multimedia production and motion analysis, which tracks the centre of mass of the silhouette image for each respective person. (www.eyesweb.org). • Using Matlab, the Psychophysics Toolbox and Showtime, these co-ordinates were filtered to reduce noise and then used to create QuickTime movies depicting white disks on a grey background. • Participants • ASC group: 4 males (age 18 – 25), diagnosed using the Autistic Diagnosis Interview (ADI). • Control group: 4 males (age 18 – 25). Animacy Displays Confusion Matrices Side View Overhead Time • Results • No significant difference between groups. • Effect of Viewpoint, F(1,6) = 9.1, p<0.05, (Overhead > Side). Video Displays Confusion Matrices Overhead Side View Time • Results • Effect of viewpoint across groups, F(1,6) = 6.3, p<0.05, (Overhead for ASC Group < Overhead Controls = Side View Controls). Conclusions • Though results are preliminary with further research and a larger clinical sample required, they suggest: • People with ASC’s can attribute intention to video displays, but this ability is greatly diminished in displays shown from an overhead perspective. • People with ASC’s are poorer at attributing intention to animacy displays compared to a control population. References Blythe, P.W., Todd, P.M., and Miller, G.F. (1999). Judging intention from motion: Basic mechanisms for social rationality. In G. Gigerenzer, P.M. Todd, and the ABC Research Group, Simple heuristics that make us smart. New York: Oxford University Press. Castelli, F., Frith, C., Happe, F. & Frith, U., (2002). Autism, Asperger syndrome and brain mechanisms for the attribution of mental states to animated shapes, Brain, 125 1839 - 1849 Heider, F., & Simmel, M., (1944). An Experimental Study of Apparent Behavior, American Journal of Psychology, 57:2. McAleer, P., Mazzarino, B., Volpe, G., Camurri, A., Patterson, H., & Pollick, F. (2004). Perceiving Animacy and Arousal in Transformed Displays of Human Interaction. Journal of Vision, 4(8), 230a.