Applause sign: is it really specific for Parkinsonian disorders? Evidence from cortical dementias

Abstract

The presence of the applause sign in cortical dementia does not confirm the specificity of the applause sign for parkinsonian disorders. The applause sign should be interpreted as a sign of frontal lobe dysfunction rather than a form of apraxia, and can likely be detected in any kind of disease which involves frontal lobe structures to some extent.

Applause sign in advanced Parkinson's disease

“…Our findings are in agreement with previous reports and show that the applause sign is present in PD [3,7], is a sign of frontal lobe involvement [4,6] and is related to the severity of illness [8]. A new finding is that patients expressing the applause sign had significantly lower scores on the Scopa-Cog, emphasizing the correlation with a higher degree of cognitive impairment.…”

Force Control Deficits in Individuals with Parkinson’s Disease, Multiple Systems Atrophy, and Progressive Supranuclear Palsy

“…One such test is the “applause sign” - the inability to stop clapping after being asked to imitate the examiner’s three handclaps [30], [31]. However, the applause sign is not specific for PSP and may generalize to other movement disorders [32], [33], [34]. One limitation of the applause sign is that it does not account for muscle activity that does not result in a clap.…”

Neurological signs of possible diagnostic value in the cognitive disorders clinic: Table 1

“…The applause sign was first shown in progressive supranuclear palsy,13 and later in other parkinsonian disorders such as Parkinson's disease, dementia with Lewy bodies, corticobasal degeneration and multiple system atrophy 14. It also occurs in cortical dementias, such as Alzheimer's disease and frontotemporal lobar degeneration, albeit less frequently than in progressive supranuclear palsy and dementia with Lewy bodies 15 16. The applause sign may be a motor perseveration, indicating frontal lobe dysfunction.…”