Glabellar and palmomental reflexes in parkinsonian disorders

The authors examined the glabellar reflex and the palmomental reflex in 100 subjects, including patients with Parkinson disease ( n = 41), patients with progressive supranuclear palsy ( n = 12), patients with multiple system atrophy ( n = 7), and healthy, age-matched, controls ( n = 40). The study provides evidence that these reflexes, particularly glabellar reflex, are relatively sensitive signs of parkinsonian disorders, but they lack specificity as they do not differentiate among the three most common parkinsonian disorders.