Damage to the cerebellum causes impairment in motor skills and can cause nystagmus. Almost a third of people with isolated, late onset<unk>  go on to develop multiple system atrophy. The cerebellum's role has been observed as not purely motor. It is combined with intellect, emotion and planning.
Cerebellar ataxia
Parkinsonian gait
Myopathic gait
Sensory ataxia
Chorea
Chorea 
Episodic ataxia
Locomotor ataxia