Purpose: When speakers retrieve words, they do so extremely quickly and accurately--both speed and accuracy of word retrieval are compromised in persons with aphasia (PWA). This study examined the contribution of two domain-general mechanisms: processing speed and cognitive control on word retrieval in PWA. Method: Three groups of participants,…

Background: The use of standardized tests specifically designed for and normed on bilingual groups is crucial for the accurate diagnosis and language profiling of bilingual speakers with aphasia. Currently, there is a dearth of norms and supporting psychometric data for the few available bilingual aphasia assessments. The only available aphasia…

Background: The ability to generate words that follow certain constraints, or verbal fluency, is a sensitive indicator of neurocognitive impairment, and is impacted by a variety of variables. Aims: To investigate the effect of post-stroke aphasia, elicitation category and linguistic variables on verbal fluency performance. Methods &…

Verb retrieval difficulties are common in aphasia; however, few successful treatments have been documented (e.g. Conroy, P., Sage, K., & Lambon Ralph, M. A. (2006). Towards theory-driven therapies for aphasic verb impairments: A review of current theory and practice. "Aphasiology", 20, 1159-1185). This study investigated the efficacy of a novel…

There are several accounts of why some individuals with post-stroke aphasia experience difficulty in producing morphologically complex verbs. Although a majority of these individuals also produce syntactically flawed utterances, at least two accounts focus on word-level encoding operations. One account proposes a difficulty with rule-governed…

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)…

Errors in the production of verb inflections, especially tense inflections, are pervasive in agrammatic Broca's aphasia ("*The boy eat"). The neurolinguistic underpinnings of these errors are debated. One group of theories attributes verb inflection errors to disruptions in encoding the verb's morphophonological form, resulting from either a…

Across most languages, verbs produced by agrammatic aphasic individuals are frequently marked by syntactically and semantically inappropriate inflectional affixes, such as "Last night, I walking home." As per language production models, verb inflection errors in English agrammatism could arise from three potential sources: encoding the verbs'…

Verb inflection errors, often seen in agrammatic aphasic speech, have been attributed to either impaired encoding of diacritical features that specify tense and aspect, or to impaired affixation during phonological encoding. In this study we examined the effect of semantic markedness, word form frequency and affix frequency, as well as accuracy…