Primary Progressive Speech Apraxia

Abstract

We investigated the clinical symptoms and pathological findings in 43 cases of primary progressive speech apraxia in 43 cases. The mean age of onset of the initial symptoms was 61.7 years, with a slight predilection for females. The time between the onset of symptoms and the medical examination was 3.4 years. The mean duration of the illness was 5.4 years for the surviving cases and 7.4 years for the 14 deceased cases. The most frequently encountered apraxia symptom is buccofacial apraxia. Neurological examination often reveals dysarthria from the beginning of the illness. As for the higher functional problems, apraxia of speech is often accompanied by executive/frontal disturbances. With regard to the radiological findings, computed tomography and magnetic resonance imaging show characteristic atrophy in the left frontal lobe. Diffuse disturbance in single photon emission computed tomography (positron emission tomography study) is seen on the more severely atrophic side. In the autopsy and biopsy examinations, one case was diagnosed with Alzheimer's disease, two with cortico basal degeneration, two with Pick's disease and three with nonspecific change. Primary progressive speech apraxia is a heterogeneous symptomatic condition; furthermore, it is suggested that the cerebral system of behavioral association might be more subdivided than was formerly believed.