In standard models of language production or comprehension, the elements which are retrieved from memory and combined into a syntactic structure are "lemmas" or "lexical items". Such models implicitly take a "lexicalist" approach, which assumes that lexical items store meaning, syntax, and form together, that…

Purpose: The impact of stimulus-level psycholinguistic variables and personlevel semantic and phonological processing skills on treatment outcomes in individuals with aphasia requires further examination to inform clinical decision making in treatment prescription and stimuli selection. This study investigated the influence of stimulus-level…

Purpose: Better performance for actions compared to objects has been reported in the semantic variant of primary progressive aphasia (svPPA). This study investigated the influence of the assessment task (naming, semantic picture matching) over the dissociation between objects and actions. Method: Ten individuals with svPPA and 17 matched controls…

Reorganization of language networks in aphasia takes advantage of the facts that (a) the brain is an organ of plasticity, with neuronal changes occurring throughout the life span, including following brain damage; (b) plasticity is highly experience dependent; and (c) as with any learning system, language reorganization involves a synergistic…

Investigating instances where lexical selection fails can lead to deeper insights into the cognitive machinery and architecture supporting successful word retrieval and speech production. In this paper, we used a multiplex lexical network approach that combines semantic and phonological similarities among words to model the structure of the mental…

Background: Until today, there is no satisfying explanation for why one language may recover worse than another in differential bilingual aphasia. One potential explanation that has been largely unexplored is that differential aphasia is the consequence of a loss of language control rather than a loss of linguistic representations. Language…

Individuals with agrammatic Broca's aphasia experience difficulty when processing reversible non-canonical sentences. Different accounts have been proposed to explain this phenomenon. The Trace Deletion account (Grodzinsky, 1995, 2000, 2006) attributes this deficit to an impairment in syntactic representations, whereas others (e.g., Caplan,…

Brain damaged participants offer an opportunity to evaluate the cognitive and linguistic processes and make assumptions about how the brain works. Cognitive linguists have been investigating the underlying mechanisms of idiom comprehension to unravel the ongoing debate on hemispheric specialization in figurative language comprehension. The aim of…

Background: Capturing evidence of the effects of therapy within everyday communication is the holy grail of aphasia treatment design and evaluation. Whilst impaired sentence production is a predominant symptom of Broca's-type aphasia, the effects of sentence production therapy on everyday conversation have not been investigated. Given the…

A theoretical framework which considers the verbal functions of the brain under a multivariate and comprehensive cognitive model was statistically analyzed. A confirmatory factor analysis was performed to verify whether some recognized aphasia constructs can be hierarchically integrated as latent factors from a homogenously verbal test. The Brief…

This study reports on the pattern of performance on spoken and written naming, spelling to dictation, and oral reading of single verbs and nouns in a bilingual speaker with aphasia in two first languages that differ in morphological complexity, orthographic transparency, and script: Greek (L1a) and English (L1b). The results reveal no verb/noun…

Two important research lines in neuro- and psycholinguistics are studying natural or experimentally induced slips of the tongue and investigating the symptom patterns of aphasic individuals. Only few studies have focused on explaining aphasic symptoms by provoking aphasic symptoms in healthy speakers. While all experimental techniques have so far…

This project examines spoken language comprehension in Broca's aphasia, a non-fluent language disorder acquired subsequent to stroke. Broca's aphasics demonstrate impaired comprehension for complex sentence constructions. To account for this deficit, one current processing theory claims that Broca's patients retain intrinsic linguistic knowledge,…

We investigate the on-line processing of verb-phrase ellipsis (VPE) constructions in two brain injured populations: Broca's and Anomic aphasics. VPE constructions are built from two simple clauses; the first is the antecedent clause and the second is the ellipsis clause. The ellipsis clause is missing its verb and object (i.e., its verb phrase…

This paper reports the results of three studies examining comprehension and real-time processing of pronominal (Experiment 1) and Wh-movement (Experiments 2 and 3) structures in agrammatic and unimpaired speakers using eyetracking. We asked the following questions: (a) Is off-line comprehension of these constructions impaired in agrammatic…