PT  - JOURNAL ARTICLE
AU  - Nogueira, Ramon
AU  - Rodgers, Chris C.
AU  - Bruno, Randy M.
AU  - Fusi, Stefano
TI  - The geometry of cortical representations of touch in rodents
AID  - 10.1101/2021.02.11.430704
DP  - 2021 Jan 01
TA  - bioRxiv
PG  - 2021.02.11.430704
4099  - http://biorxiv.org/content/early/2021/09/07/2021.02.11.430704.short
4100  - http://biorxiv.org/content/early/2021/09/07/2021.02.11.430704.full
AB  - Neural responses are often highly heterogeneous non-linear functions of multiple task variables, a signature of a high-dimensional geometry of the neural representations. We studied the representational geometry in the somatosensory cortex of mice trained to report the curvature of objects using their whiskers. High-speed videos of the whisker movements revealed that the task can be solved by linearly integrating multiple whisker contacts over time. However, the neural activity in somatosensory cortex reflects a process of non-linear integration of spatio-temporal features of the sensory inputs. Although the responses at first appear disorganized, we could identify an interesting structure in the representational geometry: different whisker contacts are disentangled variables represented in approximately, but not fully, orthogonal subspaces of the neural activity space. The observed geometry allows linear readouts to perform a broad class of tasks of different complexities without compromising the ability to generalize to novel situations.Competing Interest StatementThe authors have declared no competing interest.