Motor neuron disease (MND) or ALS is a nervous system disease. ALS leads to a loss of movement ability that eventually leads to death. At the moment, there is no known treatment for ALS. Early diagnosis in individuals improves clinical care and facilitates timely entry into clinical trials. However, current methods for diagnosis are primarily clinical, and to date, no cost-effective biomarkers have been developed. Our objective is to identify a robust non-invasive neurophysiological-based system that can be used both as a biomarker of disease onset, and a measurement of progression using quantitative EEG and surface EMG (bipolar and high-density). The investigators postulate that analysing the joint recordings of EEG and EMG (bipolar or high-density) can give measures that better distinguish healthy people and ALS patient subgroups and that the findings can be developed as biomarkers of early diagnosis and disease progression.