Augmented prenatal visual stimulation alters postnatal auditory and visual responsiveness in bobwhite quail chicks.

This study examined whether previously reported effects of altered prenatal sensory experience on subsequent acceleration of intersensory development in precocial birds are mediated by mechanisms sensitive to the overall amount of stimulation provided. Results revealed that bobwhite quail chicks exposed to substantially augmented amounts of prenatal visual stimulation show altered patterns of species-typical perceptual development. Specifically, chicks continued to respond to maternal auditory cues into later stages of postnatal development and failed to demonstrate responsiveness to maternal visual cues. Embryos also failed to demonstrate prenatal auditory learning of an individual maternal call, a behavior reliably seen in unmanipulated embryos. These findings suggest that substantially increased amounts of prenatal sensory stimulation can interfere with the emergence of species-typical patterns of postnatal intersensory functioning and lend support to the notion that sensory stimulation that falls within some optimal range maintains or facilitates normal patterns of perceptual development, whereas stimulation beyond the range of the species norm can result in intersensory interference.