8. Exploring motor imagery and motor cortical function in amyotrophic lateral sclerosis using magnetoencephalography. Issue 3 (March 2016)

• Record Type: Journal Article
• Authors: Lee, M.; Meng, D.; Kiernan, M.C.; Johnson, B.W.
• Is Part Of: Clinical neurophysiology. Volume 127:Issue 3(2016:Mar.)
• Page Start: e12
• Publication Date: 2016-03
• Subjects: Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2015.11.028
• Languages: English
• ISSNs: 1388-2457

Abstract

Abstract : Cortical neural networks underlying motor imagery overlaps with motor execution networks and can be consistently activated even by patients with motor weakness. This offers an alternative approach to study motor network activity in ALS. Owing to its high temporal resolution, magnetoencephalography (MEG) is well-suited to localise oscillatory brain wave dysfunction during both executed and motor imagery tasks. This pilot study sought to determine (i) if ALS patients can perform a validated motor imagery task; and (ii) if MEG can be used to measure cortical motor responses from ALS patients longitudinally. Spontaneous brain activity was recorded using a 160 channel whole-head KIT-Macquarie MEG in 4 ALS patients longitudinally over 9 months during a novel hand motor imagery task (Burianova et al., 2013 ). This task has been shown to consistently activate the primary motor cortex during both executed and imagined movements. Both ALS and control participants achieved high levels of accuracy in the executed and imagined tasks ( > 90%). Beta band desynchronization, an index of motor cortex activity, was observed during both executed and imagined tasks, in both cohorts. Our results showed that motor imagery could be used to probe motor cortical function in ALS patients. This has a distinct advantage over traditional method of investigating cortical function using motor execution tasks because it eliminates the bias associated with progressive muscle weakness. It is feasible to use MEG and motor imagery to (i) identify early biomarkers of cortical involvement in ALS, and (ii) to examine longitudinal effects of progressive motor neuron degeneration on cortical network function.