A model of the development of major white matter pathways within and between ventral and dorsal visual streams
Published in Journal of Vision, 2021
Recommended citation: Vinci-Booher, S., Caron, B., Bullock, D., James, K., & Pestilli, F. (2021). A model of the development of major white matter pathways within and between ventral and dorsal visual streams. Journal of Vision, 21(9), 2698-2698. https://doi.org/10.1167/jov.21.9.2698
doi: https://doi.org/10.1167/jov.21.9.2698
The ventral and dorsal visual streams process visual information for different purposes though it is clear that these two streams interact. Recent evidence shows that several white matter tracts directly connect regions associated with ventral and dorsal visual streams. Together, these white matter tracts constitute the posterior vertical pathway (PVP). As of today, we know little about PVP development and even less about its development in relation to ventral and dorsal streams. We propose a model that posits that the development of PVP white matter is related to the flow of neural activity from the ventral visual stream and to the dorsal visual stream. We characterized the development of PVP tracts in a cross-sectional sample of 31 children (4.5-8.5 years old) and 13 adults (18-22 years old) using diffusion-MRI and ensemble tractography. We measured fractional anisotropy (FA) in dorsal (i.e., SLF1and2 and SLF3) and ventral (i.e., ILF, IFOF) streams as well as the four vertical white matter tracts that constitute the PVP (i.e., TPC, pArc, MdLF-SPL, MdLF-Ang). We found that PVP microstructure was more adult-like than the microstructure of the dorsal stream tracts, suggesting that PVP white matter develops earlier than dorsal stream white matter. PVP microstructure was more similar to the microstructure of the ventral than the dorsal stream, suggesting that PVP development follows ventral stream development more closely than it follows dorsal stream development. Finally, PVP microstructure was predicted by performance on a perceptual task in children, suggesting that PVP development is related to developing visual perceptual skills. Overall, results support our model of white matter development and suggest a key role for the PVP in the development of the dorsal visual stream that may be related to its ability to facilitate interactions between ventral and dorsal streams during visual perception.
