An Eye Tracking Study Shannon Fitzhugh, Thomas F Shipley, Nora Newcombe, Dominique Dumay Temple University June 14, 2008 Individual Differences in Mental Rotation of Real World Shepard-Metzler Figures

Overview Brief Review of Individual Differences literature Identification of “new” group (Geisler, Lehmann, & Eid 2006) ‏ Eye Movements in Mental Rotation Just & Carpenter (1976) 3-dimensional stimuli Methods Results Discussion Questions????

Individual differences Focus on Gender differences Biological mechanisms Hormones (Hausmann et al.) ‏ Different areas of activation in the brain (Hugdahl et al., 2006) ‏ Experience mediates Computer experience (Terlecki & Newcombe, 2005) ‏ Training (Sorby & Baartmans, 1996; Wiedenbauer et al., 2007; Hand & Uttal, in prep) ‏

Introducing….Non-rotators Latent class analysis of MRT-A (Geisler et al., 2006) ‏ 5 “groups” of rotators Two “low” – poor MRT-A performance Three “high” – good MRT-A performance High groups – only differ in speed Response probabilities drop off after 12 (no drop off), 8, & 4 Low groups Poor mental rotators – low solution probabilities for all items Non – rotators Identified by response patterns on the MRT-A Qualitative differences between target and distracter

Examples

Eye Movements and Mental Rotation Just & Carpenter (1976) ‏ Number of fixations increased for low ability rotators Number of times switched between figures increased monotonically Search, Transform, Compare Our Expansions Greater number of subjects (them=8; us=33) ‏ Three groups of rotators (high, low, non) ‏ Statistical analysis

3-Dimensional Stimuli MRT research uses 2-Dimensional perspective drawings 3D-like virtual items (Wohlschlager & Wohlschlager, 1998) ‏ Manual training using Virtual Reality stimuli (Ruddle & Jones, 2001) ‏ Non-rotators Create stimuli amenable to their strategy to keep them above floor Application to STEM disciplines Geology, Engineering, Chemistry, Biology, Imaging

Then There Were … Real World Stimuli

Methods Vandenberg MRT (1988) Why not MRT-A? Did not have it Same items for non-rotator identification present in both tests Real World MRT 3 rotations – 0,45, and 90 degrees 2 axis rotation catch trials 30 cm viewing distance – each cube 2.5 o visual angle Applied Science Laboratories MobileEye 0.5 o error, 60hz Eye Response Technologies - GazeTracker Data Analysis Software

Dependent Variables Reaction Time Predict Linear function Number of Fixations Figure switching number of times participants switch consecutive fixations between the left and right figures Fixation Duration Intra-object v. inter-object fixations

Results – Getting Away from the Descriptive Time course of intra-object to inter-object fixations Changes over time? No differences between highs/lows Search, Transform, Compare Initially defined Transform – others by default Some preliminary evidence – although pattern a bit different Determining ways to quantify so statistical analysis can be preformed

Summary Replicate traditional MR functions with real world stimuli Linear RT function Better overall performance Replicate Just & Carpenter – with non-rotators greater number of fixations for low ability Monotonic function switching between figures for high/low Non-rotators trending toward doubling this Longer fixation duration for non-rotators Higher proportion of intra-object to inter-object fixations for high and low ability

Discussion Real World 3D stimuli behave similarly to 2D Linear reaction time Monotonic switching between figures for high/low ability Similar eye movement patterns for high/low ability Including non-rotators in low groups may have masked these similarities Similar strategies or differing strategies resulting in similar eye movements? Non-rotators Pattern of eye movements consistent with feature comparison strategy Longer fixation durations indicative of increase processing time Counting strategies

Future Directions Training study – Don’t Sleep In!! The Effects of Working Memory Training versus Spatial Visualization training on spatial skills Gesture study Eye movements, verbal report, and spontaneous gesture (Levine & Goldin-Meadow) ‏ This research was supported by a National Science Foundation grant to support the Spatial Intelligence and Learning Center (No. SBE ).

References Baartmans, B., & Sorby, S. (1996). Introduction to 3D Spatial Visualziation an interactive approach. Clifton Park, NY: Thompson Delmar Learning. Bethell-Fox, C., & Shepard, R. (1988). Mental Rotation: Effects of Stimulus Complexity and Familiarity. Journal of Experimental Psychology, 14 (1), Geiser, C., Lehmann, W., & Eid, M. (2006). Separating "Rotaters" from "Non-Rotaters" in the Mental Rotations Test: A Multigroup Latent Class Analysis. Multivariate Behavioral Research, 41 (3), Hausmann, Slabbekoorn, Goozen, V., Cohen-Kettenis, & Gunturkum. (2000). Sex hormones affect spatial abilities during the menstrual cycle. Behavioral Neuroscience, 114, Hegarty, M., & Waller, D. (2004). A dissociation between mental rotation and perspective-taking spatial abilities. Intelligence, 32, Hugdahl, K., Thomsen, T., & Ersland, L. (2006). Sex differnces in visuo-spatial processing: An fMRI study of mental rotation. Neuropsychologia, 44, Just, M., & Carpenter, P. (1985). Cognitive Coordinate Systems: Accounts of Mental Rotation and Individul Differnces in Spatial Ability. Psychological Review, 92 (2), Just, M., & Carpenter, P. (1976). Eye Fixations and Cognitive Processes. Cognitive Psychology, 8, Kozhevnikov, M., & Hegarty, M. (2001). A dissociation between object manipulation spatial ability and spatial orientation ability. Memory & Cognition, 29 (5), Peters, M. (2005). Sex differences and the factor of time in solving Vandenberg & Kuse mental rotation problems. Brain and Cognition, 57, Ruddle, R., & Jones, D. (2001). Manual and Virtual Rotation of a Three-Dimensional Object. Journal of Experimental Psychology: Applied, 7 (4), Shepard, R., & Metzler, J. (1971). Mental Rottion of Three-Dimensional Objects. Science, 171 (3972), Sorby, S. A., & Baartmans, B. J. (2000). The Development and Assessment of a Course for Enhancing the 3-D Spatial Visualization Skills of First Year Engineering Students. Journal of Engineering Education, 89 (3), Sorby, S., & Baartmans, B. (1996). A course for the development of 3D visualization skills. Engineering, Design and Graphics Journal, 60 (1). Terlecki, M., & Newcombe, N. ((in press)). Durable and generalized effects of spatial experience on mental rotation: Gender differences in growth patterns. Applied Cognitive Psychology. Terlecki, M., & Newcombe, N. (2005). How important is the digital divide? The relation of computer and video game usage to differences in mental rotation ability. Sex Roles, 53 (5/6), Voyer, Voyer, & Bryden. (1995). Magnitude of sex differences in spatial abilities: A meta analysis and consideration of critical variables. Psychological Bulletin, 117, Wiedenbauer, G., Schmid, J., & Jansen-Osmann, P. (2007). Manual Training of Mental Rotation. European Journal of Cognitive Psychology, 19 (1), Wohlschlager, A., & Wohlschlager, A. (1998). Mental and Manual Rotation. Journal of Experimental Psychology, 24 (2),