Association between activity in the ventral premotor cortex and spinal cord activation during force generation—A combined cortico‐spinal fMRI study

• Published in: Human brain mapping Vol. 44; no. 18; pp. 6471 - 6483
• Main Authors: Braaß, Hanna, Feldheim, Jan, Chu, Ying, Tinnermann, Alexandra, Finsterbusch, Jürgen, Büchel, Christian, Schulz, Robert, Gerloff, Christian
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 15.12.2023
• Subjects: Animals; Cortex (motor); Cortex (premotor); cortical motor activation; cortico‐spinal fMRI; Functional magnetic resonance imaging; grip force task; Human motion; Humans; Isometric; Magnetic Resonance Imaging; Medical imaging; Motor Cortex - diagnostic imaging; Motor Cortex - physiology; Motor skill; Neuroimaging; premotor areas; primary motor cortex; Spinal cord; Spinal Cord - diagnostic imaging; spinal motor activation; Transcranial magnetic stimulation; grip force task; cortico-spinal fMRI; premotor areas; cortical motor activation; spinal motor activation; primary motor cortex
• ISSN: 1065-9471; 1097-0193; 1097-0193
• DOI: 10.1002/hbm.26523

Force generation is a crucial element of dexterity and a highly relevant skill of the human motor system. How cerebral and spinal components interact and how spinal activation is associated with the activity in the cerebral primary motor and premotor areas is poorly understood. Here, we conducted combined cortico‐spinal functional magnetic resonance imaging during a simple visually guided isometric force generation task in 20 healthy young subjects. Activation was localized in the right cervical spinal cord and left primary motor and premotor areas. The main finding is that spinal activation was negatively correlated with ventral premotor cortex activation. Spinal activation was furthermore significantly correlated with primary motor cortex activation, while increasing target forces led to an increase in the amount of activation. These data indicate that human premotor areas such as the ventral premotor cortex might be functionally connected to the lower cervical spinal cord contributing to distal upper limb functions, a finding that extends our understanding of human motor function beyond the animal literature. A combined cortico‐spinal functional magnetic resonance imaging was conducted during a visually guided grip force task in 20 healthy young subjects. Activation was localized in the right cervical spinal cord and left primary motor and premotor areas. Spinal activation was negatively correlated with ventral premotor cortex and positive with primary motor cortex activation. These results indicate that human premotor areas might be functionally connected to the lower cervical spinal cord.