Teaching NeuroImages Neurology Resident and Fellow Section A 77 year-old woman with Parkinson’s disease exhibits re- emergent jaw tremor. © 2015 American Academy of Neurology

Vignette A 77-year-old woman had levodopa/carbidopa-responsive akinesia in her left hand and was diagnosed with Parkinson’s disease at the age of 51 years. For the previous 4 years she had jaw tremor, but no tremor in other parts of her body in off-phase. The jaw tremor was noticeably reduced during voluntary movements, such as vocalization, and initially upon biting a tongue depressor. However, the tremor reappeared after 10 seconds of continuous biting of the tongue depressor. Hatano T et al. © 2015 American Academy of Neurology

Video Hatano T et al. © 2015 American Academy of Neurology

Re-emergent tremor in Parkinson’s disease It is well known that one type of postural tremor in the forearms is a resting tremor that re-emerges after some delay while maintaining posture, namely “re-emergent tremor”. 1 The re-emergent tremor is considered to be a possible analog of the parkinsonian resting tremor. The patient’s jaw tremor is a similar phenomenon to re- emergent tremors in the hands and forearms of PD patients. Neurologists should be aware that re-emergent jaw tremor might a specific phenomenon in parkinsonian resting tremor. Hatano T et al. © 2015 American Academy of Neurology