Beta oscillations reflect changes in motor cortex inhibition in healthy ageing.
Beta oscillations are involved in movement and have previously been linked to levels of the inhibitory neurotransmitter GABA. We examined changes in beta oscillations during rest and movement in primary motor cortex (M1). Amplitude and frequency of beta power at rest and movement-related beta desynchronization (MRBD) were measured during a simple unimanual grip task and their relationship with age was explored in a group of healthy participants. We were able to show that at rest, increasing age was associated with greater baseline beta power in M1 contralateral to the active hand, with a similar (non-significant) trend in ipsilateral M1. During movement, increasing age was associated with increased MRBD amplitude in ipsilateral M1 and reduced frequency (in contralateral and ipsilateral M1). These findings would be consistent with greater GABAergic inhibitory activity within motor cortices of older subjects. These oscillatory parameters have the potential to reveal changes in the excitatory-inhibitory balance in M1 which in turn may be a useful marker of plasticity in the brain, both in healthy ageing and disease.
Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, 33 Queen Square, London, WC1N 3BG, UK. Electronic address: h.rossiter@ucl.ac.uk.
Holly E
HE
Rossiter
Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, 33 Queen Square, London, WC1N 3BG, UK.
Emma M
EM
Davis
Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, 33 Queen Square, London, WC1N 3BG, UK.
Ella V
EV
Clark
Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, 33 Queen Square, London, WC1N 3BG, UK.
Marie-Hélène
MH
Boudrias
Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, 33 Queen Square, London, WC1N 3BG, UK.
Nick S
NS
Ward
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D001611:Beta Rhythm / Q000502:physiology*; D003344:Cortical Synchronization; D003627:Data Interpretation, Statistical; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D018737:Hand Strength / Q000502:physiology; D006262:Health; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007537:Isometric Contraction; D008279:Magnetic Resonance Imaging; D015225:Magnetoencephalography; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000254:growth & development* / Q000502:physiology*; D009068:Movement / Q000502:physiology; D053580:Muscle Strength / Q000502:physiology; D009473:Neuronal Plasticity / Q000502:physiology; D011597:Psychomotor Performance / Q000502:physiology; D012146:Rest / Q000502:physiology; D055815:Young Adult; D005680:gamma-Aminobutyric Acid / Q000502:physiology
D005680:gamma-Aminobutyric Acid
Ageing; Beta; MEG; Motor; Oscillations; Plasticity