Perseverations in Alzheimer disease: Analysis of the disturbance and possible correlations

Perseverations are the involuntary repetition of a previous verbal or motorial answer, not appropriate to the current stimulus. Being attributed to frontal lobe dysfunction, they should be found in the late stage of Alzheimer's disease (AD). We evaluated 25 patients with mild to moderate AD and correlated the presence of perseverations to the severity of both the cognitive damage and the frontal involvement. We classified the perseverations according to Sandson and Albert (1) model in continuous, recurrent and stuck-in-set type and submitted patients to specific tests to identify them. All AD subjects showed one or more type of them, regardless to the severity of cognitive impairment. The stuck-in-set type was more frequent in those showing an impairment in the Stroop Test and / or Phonological Fluency Test, showing that this kind of perseveration are related to a frontal involvement.