Dynamic Object Representations in Infants with and without Fragile X Syndrome

Area of Science:

• Developmental Neuroscience
• Visual Perception
• Genetics

Background:

• Maintaining a coherent visual world requires tracking objects across time and space.
• Fragile X syndrome (FXS) is a genetic disorder linked to dorsal stream dysfunction.
• Dynamic object processing relies on the dorsal visual stream.

Purpose of the Study:

• To investigate dynamic object processing in infants with fragile X syndrome (FXS).
• To compare visual object processing in infants with FXS and typically developing (TD) infants.
• To assess the role of the dorsal stream in visual processing deficits in FXS.

Main Methods:

• Employed the violation of expectation method to assess infant visual responses.
• Used dynamic (dorsal stream) and static (ventral stream) occlusion events.
• Compared responses between infants with FXS and mental age-matched TD infants.

Main Results:

• Infants with FXS successfully maintained object identity during static occlusion.
• Infants with FXS failed to maintain object identity during dynamic occlusion.
• TD infants maintained object identity across both static and dynamic occlusion.

Conclusions:

• Infants with FXS exhibit deficits in processing dynamic object information.
• Findings support the hypothesis of dorsal stream dysfunction in infants with FXS.
• This study provides the first experimental evaluation of visual object processing in infants with FXS.