High resolution tractography in macaque visual system: validation against in vivo tracing

Structural connectivity patterns are important for understanding brain function. Diffusion imaging offers the possibility of determining in vivo connections in the human brain. Validation of this technique is important, but has proved difficult due to lack of an adequate gold standard1. The aim of this work is to use the macaque visual system as a model, in which true connections are well-known due to many detailed in vivo tracer studies2. High angular resolution diffusion imaging (HARDI) of the post-mortem macaque brain, and a probabilistic tractography approach is used, and comparisons are made between identified connections at different thresholds of connection strength, and known connections from detailed visual system wiring map first described in detail by Felleman van Essen8. 72 of connections were correctly identified