What is the definition or description of: psychomotor retardation?

Movement disorders: Psychomotor retardation is the slow down or inability to move different parts of the body..There are many causes but ultimately there is a disconnect between the brain and neurons to the peripheral nerves. The problem can begin with brain lesions in the cerebellum or other areas or depletion of the brain chemical Dopamine which is the cause of Parkinson's and other movement disorders