The vertical occipital fasciculus: A century of controversy resolved by in vivo measurements
Article Nov 18, 2014
Jason D. Yeatman, Kevin S. Weiner, Franco Pestilli, Ariel Rokem, Aviv Mezer, Brian A. Wandell.
Proceedings of the National Academy of Sciences
Abstract: The vertical occipital fasciculus (VOF) is the only major fiber bundle connecting dorsolateral and ventrolateral visual cortex. Only a handful of studies have examined the anatomy of the VOF or its role in cognition in the living human brain. Here, we trace the contentious history of the VOF, beginning with its original discovery in monkey by Wernicke (1881) and in human by Obersteiner (1888), to its disappearance from the literature, and recent reemergence a century later. We introduce an algorithm to identify the VOF in vivo using diffusion-weighted imaging and tractography, and show that the VOF can be found in every hemisphere (n = 74). Quantitative T1 measurements demonstrate that tissue properties, such as myelination, in the VOF differ from neighboring white-matter tracts. The terminations of the VOF are in consistent positions relative to cortical folding patterns in the dorsal and ventral visual streams. Recent findings demonstrate that these same anatomical locations also mark cytoarchitectonic and functional transitions in dorsal and ventral visual cortex. We conclude that the VOF is likely to serve a unique role in the communication of signals between regions on the ventral surface that are important for the perception of visual categories (e.g., words, faces, bodies, etc.) and regions on the dorsal surface involved in the control of eye movements, attention, and motion perception.
To pick apart the differences between individual cells in complex multicellular organisms, we need to look at cells one-by-one. This article takes a look at how several scientists in North America are using single cell proteomics (SCP) technologies to discern disease pathogenesis and enhance directed stem-cell differentiation.READ MORE
As many people spent the summer trying to keep the flies away from their fruit-bowls, an international group of scientists published one of the biggest and most important datasets in the field of connectomics to date, the complete 3D electron micrograph volume of the fruit-fly (Drosophila melanogaster) brain.READ MORE