Interocular suppression in adults and infants using anaglyphic stimuli: visually evoked potential measures.
Interocular suppression, assessed by monocular VEP amplitude reduction, was investigated in 3 infants, average age of 3 months, and 8 adults. A dichoptic simultaneous masking paradigm was employed, the two eyes being disassociated by red and green filters which transmitted non-overlapping wave lengths of light (anaglyphic method). One eye was continuously presented with either darkness, a diffuse green light, or two green dot patterns, containing either 20' or 80' dots. The other eye was flashed with either red diffuse light, a red 20' dot pattern, or a red 80' dot pattern. In both adults and infants, monocular VEP amplitude was reduced as the size of the continuously presented dots increased (pattern suppression) and a smaller amplitude response occurred when dots of equal size were presented than when data of different size were presented (size-specific suppression). The relative and absolute magnitudes of interocular pattern suppression were similar for adults and infants. However, the relative and absolute magnitudes of size-specific suppression were larger for adults than for infants. Pattern interocular suppression was inferred to be relatively more mature in 3 month olds than size-specific suppression. The relative lack of size-specific suppression suggests a relative immaturity of binocular spatial frequency or size channels.
D000328:Adult; D000367:Age Factors; D001921:Brain / Q000502:physiology*; D004569:Electroencephalography; D005074:Evoked Potentials, Visual; D005260:Female; D005556:Form Perception; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010364:Pattern Recognition, Visual; D014785:Vision, Ocular / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology