Synopsis of major studies on facial bradykinesia in Parkinson's disease and atypical parkinsonism (ie, progressive supranuclear palsy, multiple system atrophy and corticobasal degeneration)
| Spontaneous | Emotional | Voluntary | |
|---|---|---|---|
| PD | Karson,31 Deuschl and Goddemeier,32 Kimber and Thompson,35, Altiparmak et al,33 Agostino et al7, Bologna et al30 | Rinn43, Katsikitis et al36, Jacobs et al39, Smith et al37 Simons et al38 | Caligiuri45, Connor et al46, Korosec et al34, Agostino et al7, Bologna et al30 |
| PSP | Altiparmak et al33 Bologna et al58 | NA | Bologna et al58 |
| MSA | NA | NA | NA |
| CBD | NA | NA | NA |
PD—the spontaneous blinking rate is reduced overall. In some cases the spontaneous blinking rate is increased, suggesting a form of ‘off period’ dystonia; emotional movements: spontaneous smiling is reduced in terms of frequency and degree of mouth opening; investigations on posed expressions in PD are contradictory; voluntary orofacial movements are bradykinetic. Voluntary blinking is impaired in terms of switching between the closing and opening phases.
PSP—the spontaneous blinking rate is markedly reduced. Voluntary blinking is bradykinetic. Data on voluntary movements of the lower face and emotional facial movements are not available.
MSA and CDB—data on spontaneous, emotional and voluntary facial movements are not available.
CBD, corticobasal degeneration; MSA, multiple system atrophy; NA, not available; PD, Parkinson's disease; PSP, progressive supranuclear palsy.