TY - JOUR
T1 - Constraints on Multiple Object Tracking in Williams Syndrome
T2 - How Atypical Development Can Inform Theories of Visual Processing
AU - Ferrara, Katrina
AU - Hoffman, James E.
AU - O’Hearn, Kirsten
AU - Landau, Barbara
N1 - Funding Information:
This research was supported in part by an Integrative Graduate Education and Research Traineeship through the National Science Foundation (DGE 0549379 to KF), a T32 Postdoctoral Research Fellowship through the National Institutes of Health (5T32 HD 046388 to KF), and grants from the National Institute of Health (NINDS RO1 050876 to BL and JEH), the National Institute of Mental Health (K01 MH081191 to KH), and the National Science Foundation (BCS 1059560 to JEH).
Publisher Copyright:
Copyright © 2016 Taylor & Francis Group, LLC.
PY - 2016/8/7
Y1 - 2016/8/7
N2 - The ability to track moving objects is a crucial skill for performance in everyday spatial tasks. The tracking mechanism depends on representation of moving items as coherent entities, which follow the spatiotemporal constraints of objects in the world. In the present experiment, participants tracked 1 to 4 targets in a display of 8 identical objects. Objects moved randomly and independently (moving condition), passed behind an invisible bar (occluded condition), or momentarily disappeared by shrinking (implosion condition). Scholl and Pylyshyn (1999) found that adults can track entities under the moving and occluded conditions, but not under implosion. This finding suggests that the tracking mechanism is constrained by the spatiotemporal properties of physical objects as they move in the world. In the present study, we adapt these conditions to investigate whether this constraint holds for people with severe spatial impairments associated with Williams syndrome (WS). In Experiment 1, we compare the performance of individuals with WS and typically developing (TD) adults. TD adults replicated Scholl and Pylyshyn’s findings; performance was no different between the moving and occluded conditions but was worse under implosion. People with WS had reduced tracking capacity but demonstrated the same pattern across conditions. In Experiment 2, we tested TD 4-, 5-, and 7-year-olds. People with WS performed at a level that fell between TD 4- and 5-year-olds. These results suggest that the multiple object tracking system in WS operates under the same object-based constraints that hold in typical development.
AB - The ability to track moving objects is a crucial skill for performance in everyday spatial tasks. The tracking mechanism depends on representation of moving items as coherent entities, which follow the spatiotemporal constraints of objects in the world. In the present experiment, participants tracked 1 to 4 targets in a display of 8 identical objects. Objects moved randomly and independently (moving condition), passed behind an invisible bar (occluded condition), or momentarily disappeared by shrinking (implosion condition). Scholl and Pylyshyn (1999) found that adults can track entities under the moving and occluded conditions, but not under implosion. This finding suggests that the tracking mechanism is constrained by the spatiotemporal properties of physical objects as they move in the world. In the present study, we adapt these conditions to investigate whether this constraint holds for people with severe spatial impairments associated with Williams syndrome (WS). In Experiment 1, we compare the performance of individuals with WS and typically developing (TD) adults. TD adults replicated Scholl and Pylyshyn’s findings; performance was no different between the moving and occluded conditions but was worse under implosion. People with WS had reduced tracking capacity but demonstrated the same pattern across conditions. In Experiment 2, we tested TD 4-, 5-, and 7-year-olds. People with WS performed at a level that fell between TD 4- and 5-year-olds. These results suggest that the multiple object tracking system in WS operates under the same object-based constraints that hold in typical development.
UR - http://www.scopus.com/inward/record.url?scp=84988494771&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84988494771&partnerID=8YFLogxK
U2 - 10.1080/15248372.2016.1195389
DO - 10.1080/15248372.2016.1195389
M3 - Article
AN - SCOPUS:84988494771
SN - 1524-8372
VL - 17
SP - 620
EP - 641
JO - Journal of Cognition and Development
JF - Journal of Cognition and Development
IS - 4
ER -