Sensitivity of the human neonate to short- and long-wavelength stimuli.
Increment thresholds for long- and short-wavelength stimuli were determined under both white and orange adaptation. The forced-choice preferential looking technique (FPL) was used to test neonates shortly after birth and again at 2 months postnatal. Results were compared to an adult control group. Neonates, 2-month-olds, and adults showed a change in relative sensitivity to the 617 and 453 nm test stimuli with a change in chromatic adaptation, indicating the existence of at least 2 separately adaptable chromatic mechanisms at birth. These results are tentatively discussed in terms of the functioning of rods and short-, middle- and long-wavelength cones. A decrease in all thresholds with age is discussed with regard to attentional differences and postnatal neural development in the visual system.
D000221:Adaptation, Ocular; D000328:Adult; D000375:Aging; D003118:Color Perception / Q000502:physiology*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D012684:Sensory Thresholds / Q000502:physiology; D013053:Spectrophotometry