Past events: Hiromasa Takemura. Visual white matter tracts and retinotopic organization of the primate visual system

What: Visual white matter tracts and retinotopic organization of the primate visual system

Where: BCBL Auditorium and zoom room # 2 (If you would like to attend to this meeting reserve at info@bcbl.eu)

Who:Professor Hiromasa Takemura, PhD, National Institute for Physiological Sciences, Japan.

When:  Monday,  March 13th at 12:00 PM noon.

Over the last several decades, system neuroscience has made a substantial progress in understanding brain functions, by measuring response properties of individual brain regions and their relation to behavior. However, it is not yet well understood how such brain functions are related to the structure of the nervous system. To address such unresolved question, one needs to understand how functional organization of the brain is related to the neuroanatomy. The visual system is an ideal system to address such question since functional organization of visual areas and anatomical connections between areas are relatively well understood. In this talk, I will describe recent studies investigating the relationship between functional organization of the visual areas and neuroanatomy of the visual system. First, I will describe a recent study (Miyata et al., 2022) investigating a relationship between the size of the human primary visual cortex (V1) and the optic tract by analyzing fMRI and diffusion-weighted MRI (dMRI) in the Human Connective Project 7T Retinotopy dataset (Benson et al., 2018), based on hypothesis from a previous anatomical study (Andrews et al., 1997). Second, I will describe a series of study investigating the relationship between human extrastriate visual field maps (V3A/B and hV4) and the Vertical Occipital Fasciculus (VOF), which is a white matter tract connecting dorsal and ventral visual streams (Takemura et al., 2016). The analysis combining fMRI and dMRI suggests that the VOF is an important pathway for integration of upper and lower visual field information in the human visual system. In addition, I will discuss that such finding can be extended into non-human primate visual system (Takemura et al., 2017; 2020). Finally, I will briefly describe other recent projects in the lab, such as a percellation of the visual thalamus using quantitative MRI (Oishi et al., 2023) and comparative diffusion MRI on visual white matter pathways.