Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Case Reports
. 2024 Feb;11(2):171-174.
doi: 10.1002/mdc3.13938. Epub 2023 Dec 9.

A Case Series of Isolated Smiling Tremor: What Is the Phenomenology?

Affiliations
Case Reports

A Case Series of Isolated Smiling Tremor: What Is the Phenomenology?

Sara Radmard et al. Mov Disord Clin Pract. 2024 Feb.

Abstract

Background: Five cases of tremor only upon smiling have been reported where no facial tremor is present at rest, when talking, or with full smile.

Cases: This report highlights four cases of tremor upon partial smiling, discusses the phenomenology of smiling tremor, and reviews the current literature. Four subjects with lower facial tremor present only upon smiling underwent movement disorders evaluation with video. Tremor frequencies were determined by parsing the video clips into 1-second intervals and averaging the number of oscillations per interval and were determined to be high-frequency 8 to 10 Hz irregular facial tremors with harmonic variations upon moderate effort in all cases. Slight or full-effort smiling did not elicit facial muscle oscillations. Subjects had no other signs of tremor, dystonia, or parkinsonism on examination or in family history.

Conclusions: Tremor upon smiling only, or isolated smiling tremor, is a unique task- and position-specific tremor of the facial musculature.

Keywords: dystonic tremor; facial tremor; smiling tremor.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Single channel EMG recording of the nasalis muscle during a partial smile from case 2. Note the semi‐regular, variable duration EMG bursts.

References

    1. Silverdale MA, Schneider SA, Bhatia KP, Lang AE. The spectrum of orolingual tremor—a proposed classification system. Mov Disord 2008;23(2):159–167. 10.1002/mds.21776. - DOI - PubMed
    1. Davidson AD, Charles SK. Fundamental principles of tremor propagation in the upper limb. Ann Biomed Eng 2017;45(4):1133–1147. 10.1007/s10439-016-1765-5. - DOI - PMC - PubMed
    1. Jacome DE, Yanez GF. Tremors of the smile. JNNP 1987;50:489–490. 10.1136/jnnp.50.4.489. - DOI - PMC - PubMed
    1. Schwingenschuh P, Cordivari C, Czerny J, Esposito M, Bhatia KP. Tremor on smiling. Mov Disord 2009;24(10):1542–1545. 10.1002/mds.22666. - DOI - PubMed
    1. Kalra D, Oravivattanakul S. Tremor on smiling. Neurology 2015;84(14 Supplement): P5.277.

Publication types

LinkOut - more resources