A probabilistic atlas of finger dominance in the primary somatosensory cortex

O�Neill, George; Sengupta, Ayan; Asghar, Michael; Barratt, Eleanor; Besle, Julien; Schluppeck, Denis; Francis, Susan T.; Sanchez Panchuelo, Rosa

Abstract

With the advent of ultra-high field (7T), high spatial resolution functional MRI (fMRI) has allowed the differentiation of the cortical representations of each of the digits at an individual-subject level in human primary somatosensory cortex (S1). Here we generate a probabilistic atlas of the contralateral SI representations of the digits of both the left and right hand in a group of 22 right-handed individuals. The atlas is generated in both volume and surface standardised spaces from somatotopic maps obtained by delivering vibrotactile stimulation to each distal phalangeal digit using a travelling wave paradigm.

Metrics quantify the likelihood of a given position being assigned to a digit (full probability map) and the most probable digit for a given spatial location (maximum probability map). The atlas is validated using a leave-one-out cross validation procedure. Anatomical variance across the somatotopic map is also assessed to investigate whether the functional variability across subjects is coupled to structural differences. This probabilistic atlas quantifies the variability in digit representations in healthy subjects, finding some quantifiable separability between digits 2, 3 and 4, a complex overlapping relationship between digits 1 and 2, and little agreement of digit 5 across subjects. The atlas and constituent subject maps are available online for use as a reference in future neuroimaging studies.

Citation

O’Neill, G., Sengupta, A., Asghar, M., Barratt, E., Besle, J., Schluppeck, D., …Sanchez Panchuelo, R. (2020). A probabilistic atlas of finger dominance in the primary somatosensory cortex. NeuroImage, 217, Article 116880. https://doi.org/10.1016/j.neuroimage.2020.116880

• Journal Article Type: Article
• Acceptance Date: Apr 22, 2020
• Online Publication Date: May 4, 2020
• Publication Date: Aug 15, 2020
• Deposit Date: May 4, 2020
• Publicly Available Date: May 5, 2020
• Journal: NeuroImage
• Print ISSN: 1053-8119
• Electronic ISSN: 1095-9572
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 217
• Article Number: 116880
• DOI: https://doi.org/10.1016/j.neuroimage.2020.116880
• Keywords: Atlas, Somatosensory cortex, Digits, fMRI, Ultra-high field, Open science
• Public URL: https://nottingham-repository.worktribe.com/output/4381655
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S1053811920303669
• Additional Information: This article is maintained by: Elsevier; Article Title: A probabilistic atlas of finger dominance in the primary somatosensory cortex; Journal Title: NeuroImage; CrossRef DOI link to publisher maintained version: https://doi.org/10.1016/j.neuroimage.2020.116880; Content Type: article; Copyright: © 2020 The Authors. Published by Elsevier Inc.