Dissociation of quantifiers and object nouns in speech in focal neurodegenerative disease

Abstract

Quantifiers such as many and some are thought to depend in part on the conceptual representation of number knowledge, while object nouns such as cookie and boy appear to depend in part on visual feature knowledge associated with object concepts. Further, number knowledge is associated with a frontal-parietal network while object knowledge is related in part to anterior and ventral portions of the temporal lobe. We examined the cognitive and anatomic basis for the spontaneous speech production of quantifiers and object nouns in non-aphasic patients with focal neurodegenerative disease associated with corticobasal syndrome (CBS, n=33), behavioral variant frontotemporal degeneration (bvFTD, n=54), and semantic variant primary progressive aphasia (svPPA, n=19). We recorded a semi-structured speech sample elicited from patients and healthy seniors (n=27) during description of the Cookie Theft scene. We observed a dissociation: CBS and bvFTD were significantly impaired in the production of quantifiers but not object nouns, while svPPA were significantly impaired in the production of object nouns but not quantifiers. MRI analysis revealed that quantifier production deficits in CBS and bvFTD were associated with disease in a frontal-parietal network important for number knowledge, while impaired production of object nouns in all patient groups was related to disease in inferior temporal regions important for representations of visual feature knowledge of objects. These findings imply that partially dissociable representations in semantic memory may underlie different segments of the lexicon.

Automated analysis of lexical features in Frontotemporal Degeneration

“…However, on the assumption that patients use words with which they are more familiar in a semistructured speech sample, the more frequent use of verbs than nouns in svPPA would be contrary to the claim that the meaning of all words is degraded in svPPA. Likewise, we have showed that the meaning of words for abstract nouns is relatively preserved in svPPA (Bonner et al, 2016; Cousins et al, 2016) and that the meaning of words dependent on number knowledge is relatively preserved in svPPA (Ash et al, 2016). In a longitudinal study of lexical expression in svPPA, we found progressively reduced use of concrete words relative to abstract words (Cousins et al, 2018).…”

Linguistic Aspects of Primary Progressive Aphasia

“…Finally, svPPA patients appear to have relatively preserved knowledge of number concepts and numerosity (Cappelletti et al 2001, Crutch & Warrington 2002, Halpern et al 2004, Jefferies et al 2004), although some investigators have also noted difficulty with number knowledge in svPPA patients who are quite impaired ( Jefferies et al 2005). svPPA patients also have relatively preserved knowledge of the class of words that depend on numbers, like ‘most,’ ‘less than half,’ and ‘few,’ known as quantifiers (Ash et al 2016, Cappelletti et al 2006). While additional research is needed to fully understand the representation of object concepts in semantic memory and the degradation of these concepts in svPPA, these findings suggest that object concepts are particularly vulnerable in svPPA.…”

Relación entre el informe del cuidador sobre el habla espontánea del paciente y la Evaluación Breve de la Afasia

“…Spontaneous speech is often used to validate different neuropsychiatric attributes (11)(12)(13)(14)(15)(16) . But if multiple items representative of spontaneous speech are used, and it is also observed that the patient presents, for example, aphasia, subjecting him/her to the same failure over and over again can be harmful.…”

“…Within this framework, many psychological attributes are evaluated or validated on the basis of spontaneous speech (11)(12)(13)(14)(15)(16)(17)(18)(19) , considered as a key attribute. However, there are few studies on the validity of spontaneous speech itself, in particular, on how it is perceived by caregivers in adults with acute aphasia.…”