Understanding how the brain processes what we see from the very center of our visual gaze (foveal vision) is essential for maintaining healthy vision, including high spatial acuity vision, color vision, and visual attention. Deficits of central vision lead to blindness as in the case of macular degeneration, or loss of depth perception as in the case of lazy eye (amblyopia). Macaque monkeys have visual systems very similar to humans and thus are an ideal animal model for studies of foveal vision. During the first few months of postnatal development in the macaque monkey and first few years of life in the human, retinal photoreceptors undergo an important migration to establish the adult foveal cone and rod distribution. Despite the importance of this part of vision, there is very little known regarding cortical representation of the fovea during development. Here, we investigate the relationship between postnatal retinal photoreceptor migration and changes in foveal cortical representation in infant monkeys. Using a combination of in vivo retinal photoreceptor imaging and cortical optical imaging and electrophysiological approaches, we aim to answer questions regarding the relationship between retinal cone photoreceptor migration and changes in foveal cortical representation in the first few months of postnatal development. Multiple developmental timepoints will be studied over the first 3 postnatal months, a period when foveal cone density can be mapped with adaptive optics. Paired retinal and cortical investigation will be conducted and data correlated. Revelations regarding the mechanisms of cortical plasticity during development will have great impact on understanding the development of central vision, computational models of cortical development, and on understanding retinal and cortical bases of visual developmental disorders which may lead to new approaches to treat neurological diseases like amblyopia and improve capabilities of brain-machine interfaces for the treatment of blindness.
The goal of this proposal is to investigate the development of the brain circuits underlying central (foveal) vision, which is critical for high spatial acuity vision, color vision, and visual attention. Despite the importance foveal vision, there is very little known regarding the establishment of underlying brain circuits during development. Here we use imaging, electrophysiology, and anatomical methods to study changes in the visual cortex and corresponding changes in the retina during foveal visual development; this will provide important information for understanding and treating visual developmental disorders.
