title: Distinct Visual Evoked Potential Morphological Patterns for Apparent Motion Processing in School-Aged Children.
abstract: Measures of visual cortical development in children demonstrate high variability and inconsistency throughout the literature. This is partly due to the specificity of the visual system in processing certain features. It may then be advantageous to activate multiple cortical pathways in order to observe maturation of coinciding networks. Visual stimuli eliciting the percept of apparent motion and shape change is designed to simultaneously activate both dorsal and ventral visual streams. However, research has shown that such stimuli also elicit variable visual evoked potential (VEP) morphology in children. The aim of this study was to describe developmental changes in VEPs, including morphological patterns, and underlying visual cortical generators, elicited by apparent motion and shape change in school-aged children. Forty-one typically developing children underwent high-density EEG recordings in response to a continuously morphing, radially modulated, circle-star grating. VEPs were then compared across the age groups of 5-7, 8-10, and 11-15 years according to latency and amplitude. Current density reconstructions (CDR) were performed on VEP data in order to observe activated cortical regions. It was found that two distinct VEP morphological patterns occurred in each age group. However, there were no major developmental differences between the age groups according to each pattern. CDR further demonstrated consistent visual generators across age and pattern. These results describe two novel VEP morphological patterns in typically developing children, but with similar underlying cortical sources. The importance of these morphological patterns is discussed in terms of future studies and the investigation of a relationship to visual cognitive performance.
authors.affiliation: Central Sensory Processes Laboratory, Department of Communication Sciences and Disorders, University of Texas at Austin, Austin, TX USA.
authors.forename: Julia
authors.initials: J
authors.lastname: Campbell
authors.affiliation: Brain and Behavior Laboratory, Department of Speech, Language and Hearing Science, Institute of Cognitive Science, University of Colorado Boulder, Boulder, CO USA.
authors.forename: Anu
authors.initials: A
authors.lastname: Sharma
keywords: children; high-density EEG; sLORETA; source analysis; visual cortical development; visual evoked potentials