Stronger proprioceptive BOLD-responses in the somatosensory cortices reflect worse sensorimotor function in adolescents with and without cerebral palsy

Timo Nurmi; Julia Jaatela; Jaakko Vallinoja; Helena Mäenpää; Harri Piitulainen

doi:10.1016/j.nicl.2021.102795

Stronger proprioceptive BOLD-responses in the somatosensory cortices reflect worse sensorimotor function in adolescents with and without cerebral palsy

Neuroimage Clin. 2021:32:102795. doi: 10.1016/j.nicl.2021.102795. Epub 2021 Aug 21.

Authors

Timo Nurmi¹, Julia Jaatela², Jaakko Vallinoja², Helena Mäenpää³, Harri Piitulainen⁴

Affiliations

¹ Faculty of Sport and Health Sciences, University of Jyväskylä, FI-40014 Jyväskylä, Finland; Department of Neuroscience and Biomedical Engineering, Aalto University, FI-02150 Espoo, Finland; Aalto NeuroImaging, Aalto University, FI-02150 Espoo, Finland. Electronic address: timo.nurmi@aalto.fi.
² Aalto NeuroImaging, Aalto University, FI-02150 Espoo, Finland.
³ Pediatric Neurology, New Children's Hospital, University of Helsinki and Helsinki University Hospital, FI-00029 Helsinki, Finland.
⁴ Faculty of Sport and Health Sciences, University of Jyväskylä, FI-40014 Jyväskylä, Finland; Department of Neuroscience and Biomedical Engineering, Aalto University, FI-02150 Espoo, Finland; Aalto NeuroImaging, Aalto University, FI-02150 Espoo, Finland; Pediatric Neurology, New Children's Hospital, University of Helsinki and Helsinki University Hospital, FI-00029 Helsinki, Finland.

Abstract

Cerebral palsy (CP) is a motor disorder where the motor defects are partly due to impaired proprioception. We studied cortical proprioceptive responses and sensorimotor performance in adolescents with CP and their typically-developed (TD) peers. Passive joint movements were used to stimulate proprioceptors during functional magnetic resonance imaging (fMRI) session to quantify the proprioceptive responses whose associations to behavioral sensorimotor performance were also examined. Twenty-three TD (15 females, age: mean ± standard deviation 14.2 ± 2.4 years) and 18 CP (12 females, age: mean ± standard deviation, 13.8 ± 2.3 years; 12 hemiplegic, 6 diplegic) participants were included in this study. Participants' index fingers and ankles were separately stimulated at 3 Hz and 1 Hz respectively with pneumatic movement actuators. Regions-of-interest were used to quantify BOLD-responses from the primary sensorimotor (SM1) and secondary (SII) somatosensory cortices and were compared across the groups. Associations between responses strengths and sensorimotor performance measures were also examined. Proprioceptive responses were stronger for the individuals with CP compared to their TD peers in SM1 (p < 0.001) and SII (p < 0.05) cortices contralateral to their more affected index finger. The ankle responses yielded no significant differences between the groups. The CP group had worse sensorimotor performance for hands and feet (p < 0.001). Stronger responses to finger stimulation in the dominant SM1 (p < 0.001) and both dominant and non-dominant SII (p < 0.01, p < 0.001) cortices were associated with the worse hand sensorimotor performance across all participants. Worse hand function was associated with stronger cortical activation to the proprioceptive stimulation. This association was evident both in adolescents with CP and their typically-developed controls, thus it likely reflects both clinical factors and normal variation in the sensorimotor function. The specific mechanisms need to be clarified in future studies.

Keywords: Diplegia; Hemiplegia; Kinesthesia; Passive movement; SII; SM1.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adolescent
Cerebral Palsy*
Child
Female
Hand
Humans
Magnetic Resonance Imaging
Movement
Proprioception
Somatosensory Cortex