MND stands for Motor Neuron Disease, which is a group of progressive neurological disorders that affect the nerve cells (neurons) responsible for controlling muscle movement. The most common forms of MND are a) amyotrophic lateral sclerosis (ALS) and b) progressive bulbar palsy (PBP). The affected nerves stop sending messages to the muscles, gradually leading to weakness and thinning (atrophy/wasting) of those muscles. This is known as neurodegeneration.