Parkinson’s disease

a neurodegenerative disease characterised by shaking, a stiffness and slowness of movement whose initial causes remain unknown. It is the most frequent neurodegenerative disease as it affects 1% of the population aged over 50. It is described as a degeneration of the nerve cells of the central grey core (substantia nigra) and brings about a deficiency of dopamine secretion (see also the article ‘Dopamine at the service of movement’).