PT  - JOURNAL ARTICLE
AU  - Spencer A Arbuckle
AU  - Jeff Weiler
AU  - Erik A Kirk
AU  - Charles L Rice
AU  - Marc H Schieber
AU  - J. Andrew Pruszynski
AU  - Naveed Ejaz
AU  - Jörn Diedrichsen
TI  - Structure of population activity in primary motor cortex for single finger flexion and extension
AID  - 10.1101/2020.03.17.996124
DP  - 2020 Jan 01
TA  - bioRxiv
PG  - 2020.03.17.996124
4099  - http://biorxiv.org/content/early/2020/03/19/2020.03.17.996124.short
4100  - http://biorxiv.org/content/early/2020/03/19/2020.03.17.996124.full
AB  - How is the primary motor cortex (M1) organized to control fine finger movements? We investigated the population activity in M1 for single finger flexion and extension, using 7T functional magnetic resonance imaging (fMRI) in human participants, and compared these results to the neural spiking patterns recorded in monkeys performing the identical task. fMRI activity patterns were distinct for movements of different fingers, but quite similar for flexion and extension of the same finger. In contrast, spiking patterns in monkeys were quite distinct for both fingers and directions, similar to what was found for muscle activity patterns in humans. Given that fMRI reflects predominantly input and recurrent activity, these results suggest an architecture in which neural populations that control flexion or extension of the same finger receive similar inputs and interact tightly with each other, but produce distinct outputs.