The “applause sign” test is useful in diagnosing progressive supranuclear palsy (PSP), according to recent research. The “applause sign” is where you ask someone who might have PSP to clap. While clapping, you tell them to stop. The person with PSP continues to clap; it takes them awhile to stop.
In a study done by Dubois, 30 out of 42 patients diagnosed with PSP could not stop applauding immediately after being told to stop. None of those with frontotemporal dementia (FTD) or Parkinson’s Disease (PD) had trouble stopping.
So I guess the part of the brain that controls this process is not affected by PD or FTD…? The “applause sign” is an indication of “motor perseveration.” Perhaps this is controlled by the frontal lobe so interesting that it’s not affected in FTD.
I’ll ask the neurologist to do this in Dad’s next appt. I’m interested in seeing this.
Copied below is part of the abstract of the Dubois article (published 6/05 in Neurology) from PubMed (pubmed.gov).
“Applause sign” helps to discriminate PSP from FTD and PD
The “applause sign” is a simple test of motor control that helps to differentiate PSP from frontal or striatofrontal degenerative diseases. It was found in 0/39 controls, 0 of 24 patients with frontotemporal dementia (FTD), 0 of 17 patients with Parkinson disease (PD), and 30/42 patients with progressive supranuclear palsy (PSP). It discriminated PSP from FTD (p < 0.001) and PD (p < 0.00). The “three clap test” correctly identified 81.8% of the patients in the comparison PSP and FTD and 75% of the patients in the comparison of PSP and PD.