<prompt> Parkinsonism differ from atypical parkinsonism by the absence ofResting tremorPostural instabilityVeical gaze palsyGait abnormality  <response>: Atypical Parkinsonisms Characterised by Progressive supranuclear palsy Coicobasal ganglionic degeneration Frontotemporal dementia Multiple-system atrophy aCerebellar type MSA-c bParkinson type MSA-p Poor response to dopamine early loss of balance prominent intellectual changes rapid onset of progression conspicuous postural hypotension urinary bowel incontinence Little or no tremor Reference: Chapter 372. Parkinsons Disease and Other Movement Disorders Harrisons Principles of Internal Medicine 18th edition 