The rise and fall of frequency and imageability: Noun and verb production in semantic dementia

Helen Bird, Matthew A. Lambon Ralph, Karalyn Patterson, John R. Hodges

    Research output: Contribution to journalArticlepeer-review

    736 Downloads (Pure)

    Abstract

    This study examines the impact of progressive degeneration of conceptual knowledge on the content words used in connected speech elicited using the Cookie Theft picture description (Goodglass and Kaplan, 1983). We began with an analysis of control subjects' descriptions with regard to word types and their frequency and imageability. Because the impairment of conceptual knowledge in semantic dementia is graded by concept familiarity, we created a model of a standardized normal Cookie Theft description that was then progressively degraded by the systematic removal of lower bands of word frequency. We drew two main predictions from this model: reduced availability of the lower bands of word frequency should result in (a) an apparent deficit for noun retrieval in relation to verb retrieval and (b) an apparent reverse imageability effect. Results from a longitudinal study, in which three patients with semantic dementia each described the Cookie Theft picture on three occasions during the progression of their disease, confirmed these predictions. An additional cross-sectional analysis, adding narratives from a larger number of cases, demonstrated that the decline in ability to produce suitable words for the picture description is closely related to the extent of semantic impairment as measured in tests of word comprehension and production. Both verbs and nouns are affected by the degradation of semantic memory; the fact that the impairment to noun production is manifested earlier and more catastrophically may be attributed to the relatively lower frequency of these terms. (C) 2000 Academic Press.
    Original languageEnglish
    Pages (from-to)17-49
    Number of pages32
    JournalBrain and Language
    Volume73
    Issue number1
    DOIs
    Publication statusPublished - 1 Jun 2000

    Keywords

    • Cookie Theft
    • Frequency
    • Imageability
    • Narrative
    • Nouns
    • Picture description
    • Progressive aphasia
    • Semantic dementia
    • Spontaneous speech
    • Verbs

    Fingerprint

    Dive into the research topics of 'The rise and fall of frequency and imageability: Noun and verb production in semantic dementia'. Together they form a unique fingerprint.

    Cite this