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…

Sentence comprehension requires both syntactic prediction and working memory processes. Evidence suggests that both are impaired in agrammatic aphasia, and can independently contribute to comprehension breakdowns, but the relationship between them, especially during real-time sentence comprehension remains unclear. Two EEG studies investigated…

Purpose: Pupillary responses captured via pupillometry (measurement of pupillary dilation and constriction during the performance of a cognitive task) are psychophysiological indicators of cognitive effort, attention, arousal, and resource engagement. Pupillometry may be a promising tool for enhancing our understanding of the relationship between…

Purpose: Although there is increasing interest in using structural priming as a means to ameliorate grammatical encoding deficits in persons with aphasia (PWAs), little is known about the precise mechanisms of structural priming that are associated with robust and enduring effects in PWAs. Two dialogue-like comprehension-to-production priming…

Background: Despite its importance, in-depth analysis of connected speech is often neglected in the diagnosis of primary progressive aphasia (PPA) -- especially for the logopenic variant (lvPPA) for which unreliable differential diagnosis has been documented. Only a few studies have been conducted on this topic in lvPPA. Aims: The aim of this…

Purpose: Arousal and cognitive effort are relevant yet often overlooked components of attention during language processing. Pupillometry can be used to provide a psychophysiological index of arousal and cognitive effort. Given that much is unknown regarding the relationship between cognition and language deficits seen in people with aphasia (PWA),…

Purpose: Aphasia is a complex, neurogenic language disorder, with different aphasia syndromes hallmarked by impairment in fluency, auditory comprehension, naming, and/or repetition. Broad, standardized assessments of language domains and specific language and cognitive assessments provide a holistic impairment profile of a person with aphasia.…

Purpose: Persons with aphasia (PWAs) have been shown to have impaired attention skills that may interfere with their ability to successfully participate in speech and language therapy. Fluctuations in attention can be detected using physiological measures such as electroencephalography (EEG), but these measures can be impractical for clinical use.…

Background: Given the integral role that verbs play in sentence production, understanding verb deficits is critical to clinical practice. Difficulties in sentence production are often directly related to an inability to retrieve argument structure information which, according to most theoretical accounts, is specified at a lexical level as part of…

Purpose: This study investigated the relationship between non-orthographic language abilities and reading in order to examine assumptions of the primary systems hypothesis and further our understanding of language processing poststroke. Method: Performance on non-orthographic semantic, phonologic, and syntactic tasks, as well as oral reading and…

Purpose: Previous eye-tracking research has suggested that individuals with aphasia (IWA) do not assign syntactic structure on their first pass through a sentence during silent reading comprehension. The purpose of the present study was to investigate the time course with which lexical variables affect silent reading comprehension in IWA. Three…

Purpose: The present work investigated whether verbal working memory (WM) affects morphosyntactic production in configurations that do not involve or favor similarity-based interference and whether WM interacts with verb-related morphosyntactic categories and/or cue-target distance (locality). It also explored whether the findings related to the…

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…

This dissertation explores how listeners extract meaning from personal and reflexive pronouns in spoken language. To be understood, words like her and herself must be linked to a prior element in the speech stream (or antecedent). This process draws on syntactic knowledge and verbal working memory processes. I present two original research studies…

Background: Aphasia is characterized by difficulties in connected speech/writing. Aims: To explore the differences between the oral and written description of a picture in individuals with chronic aphasia (IWA) and healthy controls. Descriptions were controlled for productivity, efficiency, grammatical organization, substitution behaviour and…