title: Differential involvement of cortical and cerebellar areas using dominant and nondominant hands: An FMRI study.
abstract: Motor fMRI studies, comparing dominant (DH) and nondominant (NDH) hand activations have reported mixed findings, especially for the extent of ipsilateral (IL) activations and their relationship with task complexity. To date, no study has directly compared DH and NDH activations using an event-related visually guided dynamic power-grip paradigm with parametric (three) forces (GF) in healthy right-handed subjects. We implemented a hierarchical statistical approach aimed to: (i) identify the main effect networks engaged when using either hand; (ii) characterise DH/NDH responses at different GFs; (iii) assess contralateral (CL)/IL-specific and hemisphere-specific activations. Beyond confirming previously reported results, this study demonstrated that increasing GF has an effect on motor response that is contextualised also by the use of DH or NDH. Linear analysis revealed increased activations in sensorimotor areas, with additional increased recruitments of subcortical and cerebellar areas when using the NDH. When looking at CL/IL-specific activations, CL sensorimotor areas and IL cerebellum were activated with both hands. When performing the task with the NDH, several areas were also recruited including the CL cerebellum. Finally, there were hand-side-independent activations of nonmotor-specific areas in the right and left hemispheres, with the right hemisphere being involved more extensively in sensori-motor integration through associative areas while the left hemisphere showing greater activation at higher GF. This study shows that the functional networks subtending DH/NDH power-grip visuomotor functions are qualitatively and quantitatively distinct and this should be taken into consideration when performing fMRI studies, particularly when planning interventions in patients with specific impairments.
authors.affiliation: Department of Diagnostic Radiology, Faculty of Applied Medical Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia|NMR Research Unit, Department of Neuroinflammation, Queen Square MS Centre, University College London (UCL), Institute of Neurology, London, United Kingdom
authors.forename: Adnan A S
authors.initials: AA
authors.lastname: Alahmadi
authors.affiliation: Department of Diagnostic Radiology, Faculty of Applied Medical Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia|Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics and Maternal and Child Health, University of Genoa, Genoa, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Pardini
authors.affiliation: Department of Diagnostic Radiology, Faculty of Applied Medical Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia
authors.forename: Rebecca S
authors.initials: RS
authors.lastname: Samson
authors.affiliation: Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy.|Brain Connectivity Center, C. Mondino National Neurological Institute, Pavia, Italy.
authors.forename: Egidio
authors.initials: E
authors.lastname: D'Angelo
authors.affiliation: Wellcome Centre for Imaging Neuroscience, UCL Institute of Neurology, University College London, London, United Kingdom.
authors.forename: Karl J
authors.initials: KJ
authors.lastname: Friston
authors.affiliation: Department of Diagnostic Radiology, Faculty of Applied Medical Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia|NMR Research Unit, Department of Brain Repair and Rehabilitation, Queen Square MS Centre, UCL Institute of Neurology, London, United Kingdom.
authors.forename: Ahmed T
authors.initials: AT
authors.lastname: Toosy
authors.affiliation: Department of Diagnostic Radiology, Faculty of Applied Medical Science, King Abdulaziz University (KAU), Jeddah, Saudi Arabia|Brain Connectivity Center, C. Mondino National Neurological Institute, Pavia, Italy.
authors.forename: Claudia A M
authors.initials: CA
authors.lastname: Gandini Wheeler-Kingshott
mesh_terms: D000328:Adult; D001931:Brain Mapping; D002531:Cerebellum / Q000098:blood supply* / Q000502:physiology; D002540:Cerebral Cortex / Q000098:blood supply* / Q000502:physiology; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006225:Hand; D018737:Hand Strength / Q000502:physiology*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009068:Movement / Q000502:physiology*; D010100:Oxygen / Q000097:blood
chemical_list: D010100:Oxygen
keywords: FMRI; contra-lateral; dominant; force; squeeze-ball