Narrative discourse is an essential component of day-to-day communication, but little is known about narrative in Lewy body spectrum disorder (LBSD), including Parkinson's disease (PD), Parkinson's disease with dementia (PDD), and dementia with Lewy bodies (DLB). We performed a detailed analysis of a semi-structured speech sample in 32 non-aphasic…

Agrammatic aphasic individuals exhibit marked production deficits for tense morphology. This paper presents three experiments examining whether a group of English-speaking agrammatic individuals (n = 10) exhibit parallel deficits in their comprehension of tense. Results from two comprehension experiments (on-line grammaticality judgment studies)…

This study tested the production of tensed finite verbs and participles referring to the past and future in agrammatic speakers of Turkish. The agrammatic speakers did not make more time reference errors in tensed verbs than in participles. This is interesting because tense in general cannot therefore be the main problem, since time reference for…

Within a discrete two-stage model of lexicalization, semantic errors and errors of omission are assumed to be independent events. In contrast, cascading and interactive models allow for an influence of word form on lexical selection and thus for an inherent relationship in accounting for both error types. A group of 17 aphasic patients was…

Neurolinguistic research has been engaged in evaluating models of language using measures from brain structure and function, and/or in investigating brain structure and function with respect to language representation using proposed models of language. While the aphasiological strategy, which classifies aphasias based on performance modality and a…

In this study we investigate the production of verb inflection in agrammatic aphasia. In a number of recent studies it has been argued that tense inflection is harder to produce for agrammatic individuals than agreement inflection. However, results are still inconclusive, at least for Dutch and German. Here, we report three experiments in which…

Is it necessary to posit separate, explicit distinctions between representations in order to account for dissociations between consonant and vowel processing? We argue that a cognitive model of speech production based on cumulative lower-level properties is not only sufficient but more parsimonious in accounting for aphasic and dysgraphic patient…

Neurolinguistic research has been engaged in evaluating models of language using measures from brain structure and function, and/or in investigating brain structure and function with respect to language representation using proposed models of language. While the aphasiological strategy, which classifies aphasias based on performance modality and a…

Verb production is notoriously difficult for individuals with Broca's aphasia, both at the word and at the sentence level. An intriguing question is at which level in the speech production these problems arise. The aim of the present study is to identify the functional locus of the impairment that results in verb production deficits in Broca's…

This study presents results from sentence-completion and grammaticality-judgment tasks with 7 German-speaking agrammatic aphasics and 7 age-matched control subjects examining tense and subject-verb agreement marking. For both experimental tasks, we found that the aphasics achieved high correctness scores for agreement, while tense marking was…

Ten cerebellar patients were compared to 10 control subjects on a verbal working memory task in which the phonological similarity of the words to be remembered and their modality of presentation were manipulated. Cerebellar patients demonstrated a reduction of the phonological similarity effect relative to controls. Further, this reduction did not…

The Wernicke-Lichtheim-Geschwind (WLG) theory of the neurobiological basis of language is of great historical importance, and it continues to exert a substantial influence on most contemporary theories of language in spite of its widely recognized limitations. Here, we suggest that neurobiologically grounded computational models based on the WLG…