CHARACTERIZING GESTURAL DISTURBANCES IN P RIMARY PROGRESSIVE APRAXIA - IMPLICATIONS FOR DIAGNOSIS AND NOSOGRAPHY

Five cases are reported of patients with so-called primary progressive apraxia, defined as a slowly worsening disturbance of gestural abilit ies, without other major cognitive changes during a long period, in re lation to degenerative cortical atrophy. All five cases, as other case s in the litterature, share the following common features : 1) asymmet rical onset of upper limb clumsiness, more often involving the left si de, later involving the contralateral side and lower limbs; 2) after a variable delay; the occurrence of symptoms suggesting subcortical inv olvement (akinesia, limb stiffness, various kinds of movement disorder s, dystonia, paresis of vertical gaze); 3) diffuse cortical atrophy ty pically more pronounced in the superior parietal cortex opposite to th e first side affected. The unusual nature of apraxia in all these case s is pointed out and referred to as Luria's ''kinesthaesic apraxia'' a scribed to a loss of ''selectivity'' of distal elementary movements. T his pattern of symptoms and their specific outcome could represent a d istinct entity.