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bioRxiv · 10.1101/2020.04.13.039495

Temporo-parietal brain regions are involved in higher order object perception

Abstract

Lesions to posterior temporo-parietal brain regions are associated with deficits in perception of global, hierarchical shapes, but also impairments in the processing of objects presented under demanding viewing conditions. Evidence from neuroimaging studies and lesion patterns observed in patients with simultanagnosia and agnosia for object orientation suggest similar brain regions to be involved in perception of global shapes and processing of objects in atypical ( non-canonical) orientation. In a localizer experiment, we identified individual temporoparietal brain areas involved in global shape perception and found significantly higher BOLD signals during the processing of non-canonical compared to canonical objects. In a multivariate approach, we demonstrated that posterior temporo-parietal brain areas show distinct voxel patterns for non-canonical and canonical objects and that voxel patterns of global shapes are more similar to those of objects in non-canonical compared to canonical viewing conditions. These results suggest that temporo-parietal brain areas are not only involved in global shape perception but might serve a more general mechanism of complex object perception. Our results challenge a strict attribution of object processing to the ventral visual stream by suggesting specific dorsal contributions in more demanding viewing conditions. HighlightsO_LIPosterior temporo-parietal brain areas in the TPJ region that are involved in global shape perception are significantly involved in object perception C_LIO_LIIndividual global shape TPJ ROIs identified with a specific localizer experiment prefer objects in non-canonical over objects in canonical orientations C_LIO_LIUnivariate activations and multivariate voxel patterns in global shape TPJ ROIs distinguish canonical and non-canonical object presentations C_LI

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BibTeXRIS

Nestmann, S., Wiesen, D., Karnath, H.-O., Rennig, J.. 2020-04-14. Temporo-parietal brain regions are involved in higher order object perception. https://doi.org/10.1101/2020.04.13.039495

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