August 2023
Volume 23, Issue 9
Open Access
Vision Sciences Society Annual Meeting Abstract  |   August 2023
Reduced perception-action dissociation in children with amblyopia
Author Affiliations & Notes
  • Zoha Ahmad
    York University
  • Krista Kelly
    Retina Foundation of the Southwest
  • Erez Freud
    York University
  • Footnotes
    Acknowledgements  This research was funded by Natural Sciences and Engineering Research Council of Canada (NSERC) (EF), Vision Science to Applications (VISTA) program funded by the Canada First Research Excellence Fund (CFREF) (ZA&EF), and by the National Institutes of Health (NIH, EY028224) (KK).
Journal of Vision August 2023, Vol.23, 4849. doi:
  • Views
  • Share
  • Tools
    • Alerts
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Zoha Ahmad, Krista Kelly, Erez Freud; Reduced perception-action dissociation in children with amblyopia. Journal of Vision 2023;23(9):4849.

      Download citation file:

      © ARVO (1962-2015); The Authors (2016-present)

  • Supplements

Visual illusions differentially affect perception and action, providing insights into the functional dissociation between vision for perception and vision for action. One such illusion is the Ponzo illusion where perceptual behaviors are modulated by the monocular depth cues, while grasping trajectories resist the effect of the illusion. Children with amblyopia (poor vision in one eye) provide the opportunity to examine an outstanding question - to what extent normal visual experience is critical for the development of the perception-action functional dissociation. Here, we examined the effect of the Ponzo illusion on perception and action in a group of children with amblyopia (n=20, 9.1±2.2 years old) compared to typically developed children (n=20, 9.2±2.1 years old). In the incongruent trials, two objects that differ in their real size (40 & 42 mm) were placed on an illusory Ponzo background to create a conflict between the real and the perceived size of the object and vice versa in the congruent trials. Control and amblyopic participants were asked to grasp (action task) and manually estimate the length of the object (perceptual task). Across conditions, we recorded hand kinematics using the Optitrack motion capture system. Both groups showed equal effect of the illusion in the perceptual task, such that the object placed on the far surface was perceived as longer compared to when placed on the near surface. In contrast, a clear differentiation between the groups was observed for the grasping task. While amblyopic participants’ Maximum Grip Apertures (MGAs) were modulated by the illusion, the MGAs of typically developed children evaded the illusion and were scaled to the real size of the object regardless of the object’s placement on the background. Taken together, our results provide novel evidence that atypical visual experience in childhood from amblyopia impacts the development of the dissociation between perception and action.


This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.