Ideomotor apraxia in agrammatic and logopenic variants of primary progressive aphasia

Abstract

There are few studies examining praxis in subjects with primary progressive aphasia. The aim of this study was to examine the pattern and severity of ideomotor apraxia in subjects with logopenic and agrammatic variants of primary progressive aphasia and to determine if the presence of ideomotor apraxia correlated with specific neuroanatomical structural abnormalities. Subjects with primary progressive aphasia were prospectively recruited and classified according to published criteria. Using the apraxia subtest of the Western Aphasia Battery, pattern and severity of ideomotor apraxia was examined in all subjects diagnosed with agrammatic and logopenic variants of primary progressive aphasia. The study included 47 subjects, 21 diagnosed with agrammatic variant of primary progressive aphasia and 26 with logopenic variant primary progressive aphasia. Subjects with agrammatic aphasia were older at onset than the logopenic variant (67.2 versus 61.7 years, p=0.02), but there was no difference in illness duration prior to evaluation. Those with logopenic aphasia showed more cognitive impairment on the Mini-Mental Status Examination (agrammatic=26.7/30, logopenic=22/30, p=0.002), and a trend for more severe language impairment as measured by Western Aphasia Battery-Aphasia Quotient (agrammatic=82.3, logopenic=75.2, p=0.11). Strong correlations were found between Western Aphasia Battery-Aphasia Quotient and total apraxia, instrumental apraxia, and complex apraxia, while average correlation were seen with upper limb apraxia and modest correlation with facial apraxia. After adjusting for age, mental status performance, and Western Aphasia Battery-Aphasia Quotient score, those with agrammatic aphasia had a higher degree of total apraxia (p=0.004), facial apraxia (p=0.03), instrumental apraxia (p=0.0006), and complex apraxia (p=0.0006) than those with logopenic aphasia. The agrammatic variant of primary progressive aphasia was associated with greater praxis deficits but less cognitive impairment than the logopenic variant. The presence of ideomotor apraxia was associated with grey matter loss in the left lateral premotor cortex with extension into the motor cortex. These findings suggest that although some affected areas in the agrammatic and logopenic variants of primary progressive aphasia overlap, there exists an area that is more affected in the agrammatic variant than the logopenic variant that accounts for the greater association of agrammatic aphasia with apraxia.

Apraxia profile differentiates behavioural variant frontotemporal from Alzheimer's dementia in mild disease stages

“…In this sense, the production deficits for face postures in bvFTD may be associated to an encoding deficit, as previously shown in these patients 37. Moreover, face apraxia has previously been reported in the language variants of frontotemporal lobar degeneration alongside with apraxia of speech 10 39. These studies showed associations between face apraxia and volume loss in left frontal brain areas, particularly the middle frontal gyrus, premotor cortex and frontal operculum, but most importantly not with parietal cortices.…”

“…However, the strict dependency on parietal lobe function for praxis tasks has recently been challenged 4. Praxis subdomains have been linked to areas in the frontal lobes in healthy controls (HC)8 and accordingly in disorders characterised by frontal lobe dysfunctions such as primary progressive aphasia,9 corticobasal degeneration10 and schizophrenia 11. Yet, apraxia has not been evaluated in behavioural variant frontotemporal dementia (bvFTD), a neurodegenerative disease that is characterised by early and progressive atrophy of the medial frontal cortex 12.…”

Nonverbal oral apraxia in primary progressive aphasia and apraxia of speech

“…1 A small study of patients with degenerative agrammatic aphasia, which included patients with neurodegenerative disorders other than PPA who had agrammatic aphasia, suggested that limb apraxia among patients with agrammatic aphasia was the result of atrophy of the left inferior parietal lobe, whereas apraxia of speech and NVOA were associated with more anterior atrophy involving the left posterior-inferior frontal gyrus and the middle frontal and premotor cortices, respectively. 3 We previously reported 4 ideomotor apraxia among patients with agPPA (although this included patients who would now be classified as PAOS) and patients with LPA, and found that the composite apraxia score as measured on the WAB correlated with gray matter loss in the left lateral premotor cortex, especially the middle frontal gyrus, with some extension into motor cortex. Furthermore, a poorer ideomotor apraxia score implied a significantly higher OR for belonging to the agPPA as opposed to the LPA group.…”

“…The same is true of NVOA among patients with apraxia of speech and ideomotor apraxia. Two recent studies 3,4 described the presence of apraxia, including facial apraxia, among patients with progressive nonfluent aphasia and logopenic aphasia (LPA). Similarly, NVOA has been mentioned in the setting of disorders dominated by apraxia of speech, 5 but little is known about its association with apraxia of speech or ideomotor apraxia.…”

Particularités du variant logopénique au sein des aphasies progressives primaires

“…Cette symptomatologie gestuelle fine est diffé rente de celle observé e dans les APP agrammatiques qui pré sentent des troubles plus diffus avec notamment une apraxie idé omotrice plus importante [64].…”