Forced
yawning as a pseudobulbar sign in amyotrophic
lateral sclerosis (als)
Elisabeth S. Louwerse, F. Eelco
Posthumus-Meyjes, Dirk Troost and J.M.B. Vianney
de Jong
Dept. Neurology, Academic
Centre at the University of Amsterdam, The
Nelherlands
In a series of 200 consecutive ALS patients,
23 exhibited bouts of prolonged, intensive
and uncontrolled yawning. All of the
patients with symptoms of yawning had signs of
pseudobulbar and bulbar paresis, with positive
pseudobulbar reflexes and forced crying or
forced laughter.
In one woman, bouts of yawning caused
habitual subluxation of the mandible several
times per night. Yawning caused great
embarrassment to a patient in whom it came on
whenever she was happy about being visited by
close friends. In another, we could provoke
yawning by eliciting the plantar responses.
Synchronously with the bouts of yawning, one
patient exhibited forced
extension of a paretic arm. We will report
the autopsy findings in one case.
We conclude that, like forced crying and
forced laughter, forced yawning is a sign of
pseudobulbar involvement in ALS.
