Effects of dominant and non-dominant passive arm manoeuvres on the neurovascular coupling response.

Osian Llwyd,Thompson G Robinson,Ronney B Panerai

doi:10.1007/s00421-017-3707-9

Abstract

Models designed to study neurovascular coupling (NVC) describe a possible cerebral hemisphere dominance dependent on task completed and preference in handedness. We investigated whether passive arm manoeuvre performed with dominant (Dom-Arm) or non-dominant arm (ND-Arm) stimulated haemodynamic differences in either contralateral (Cont-H) or ipsilateral (Ipsil-H) cerebral hemisphere. Healthy individuals lying in supine position, had measurements of beat-to-beat blood pressure (BP, mmHg), electrocardiogram (HR, bpm), end-tidal CO2 (etCO2, mmHg), and bilateral insonation of the middle cerebral arteries (MCA, cms-1). Arm movement was performed for 60s with passive flexion and extension of the elbow (1Hz), before manoeuvre was repeated on other arm. Data were normalised and effect of treatment was analysed for differences between manoeuvres and within each time period. Seventeen (eight males) healthy volunteers, aged 56±7years, were studied. Dom-Arm and ND-Arm manoeuvres stimulated a comparable temporal response in peripheral and cerebral haemodynamic parameters between Cont-H and Ipsil-H. Both manoeuvres can be used to evoke similar bilateral MCA responses in assessing NVC. This finding should lead to more efficient protocols when using passive arm movement for NVC studies in healthy subjects.

Highlights

Neurovascular coupling (NVC) describes the association between neuronal activity and the localised response in cerebral blood flow (CBF) that is needed to suffice metabolic demand
One limitation to this study (Salinet et al 2013) was that only Dom-Arm was used to study healthy controls, whereas depending on the handedness of the patient and the side affected by hemiparesis, both Dom-Arm or the non-dominant arm (ND-Arm) were used to stimulate NVC in the stroke population
Data are presented for 17 individuals (8 male), with a mean ± standard deviation (SD) age of 56 ± 7 years

Summary

Introduction

Neurovascular coupling (NVC) describes the association between neuronal activity and the localised response in cerebral blood flow (CBF) that is needed to suffice metabolic demand. To study NVC in humans, brain activity within specific regions can be stimulated with a range of tasks that are visual (Yamaguchi et al 2014), motor (Hirth et al 1997), or cognitive (Williams et al 2017) in nature. These paradigms will promote a transient hyperaemic response that can be measured with functional neuroimaging techniques such as positron emission tomography (PET) (Colebatch et al 1991), functional magnetic resonance imaging (fMRI) (Rao et al 1993) or near infrared spectroscopic imaging (Hirth et al 1997). One limitation to this study (Salinet et al 2013) was that only Dom-Arm was used to study healthy controls, whereas depending on the handedness of the patient and the side affected by hemiparesis, both Dom-Arm or the non-dominant arm (ND-Arm) were used to stimulate NVC in the stroke population

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