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bioRxiv · 10.1101/2021.02.16.431444

THE COMPLEX HODOLOGICAL ARCHITECTURE OF THE MACAQUE DORSAL INTRAPARIETAL AREAS AS EMERGING FROM NEURAL TRACERS AND DW-MRI TRACTOGRAPHY

Caminiti, R.·Girard, G.·Battaglia Mayer, A.·Borra, E.·Schito, A.·Innocenti, G. M.·Luppino, G.
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Abstract

In macaque monkeys, dorsal intraparietal areas are involved in several daily visuo-motor actions. However, their border and sources of cortical afferents remain loosely defined. Through a retrograde tracer and MRI diffusion-based tractography study here we show a complex organization of the dorsal bank of the IPS, which can be subdivided into a rostral area PEip, projecting to the spinal cord, and a caudal area MIP lacking such projections. Both areas include a rostral and a caudal sector, emerging from their ipsilateral, gradient-like connectivity profiles. As tractography estimations, we used the cross-sectional volume of the white matter bundles connecting each area with other parietal and frontal regions, after selecting ROIs corresponding to the injection sites of retrograde tracers. A quantitative analysis between the proportions of cells projecting to all sectors of PEip and MIP along the continuum of the dorsal bank of the IPS and tractography revealed a significant correlation between the two data sets for most connections. Moreover, tractography revealed "false positive" but plausible streamlines awaiting histological validation.

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Caminiti, R., Girard, G., Battaglia Mayer, A., Borra, E., Schito, A., Innocenti, G. M., Luppino, G.. 2021-02-17. THE COMPLEX HODOLOGICAL ARCHITECTURE OF THE MACAQUE DORSAL INTRAPARIETAL AREAS AS EMERGING FROM NEURAL TRACERS AND DW-MRI TRACTOGRAPHY. https://doi.org/10.1101/2021.02.16.431444

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