Purpose: Persons with aphasia (PWA) experience differences in attention after stroke, potentially impacting cognitive/language performance. This secondary analysis investigated physiologically measured vigilant attention during linguistic and nonlinguistic processing in PWA and control participants. Method: To evaluate performance and attention in…

Purpose: Lexical processing impairments such as delayed and reduced activation of lexical-semantic information have been linked to syntactic processing disruptions and sentence comprehension deficits in individuals with aphasia (IWAs). Lexical-level deficits can also preclude successful lexical encoding during sentence processing and amplify the…

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…

Background: Aphasia is often accompanied by impairment of non-language cognitive functions. Assessment of cognitive capacity in people with aphasia (PWA) with standard neuropsychological methods may be problematic due to their language difficulties. Numerous experimental studies indicate that P300 may be considered as an index of cognitive…

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,…

Purpose: Brain imaging has provided puzzle pieces in the understanding of language. In neurologically healthy populations, the structure of certain brain regions is associated with particular language functions (e.g., semantics, phonology). In studies on focal brain damage, certain brain regions or connections are considered sufficient or…

Purpose: Cognitive effort is a clinically important facet of linguistic processing that is often overlooked in the assessment and treatment of people with aphasia (PWA). Furthermore, there is a paucity of valid ways to index cognitive effort in PWA. The construct of cognitive effort has been indexed for decades via pupillometry (measurement of…

Both taxonomic and thematic semantic relations have been studied extensively in behavioral studies and there is an emerging consensus that the anterior temporal lobe plays a particularly important role in the representation and processing of taxonomic relations, but the neural basis of thematic semantics is less clear. We used eye tracking to…

Background: Temporal information processing (TIP) underlies many aspects of cognitive functions like language, motor control, learning, memory, attention, etc. Millisecond timing may be assessed by sequencing abilities, e.g. the perception of event order. It may be measured with auditory temporal-order-threshold (TOT), i.e. a minimum time gap…

Wernicke's aphasia (WA) is the classical neurological model of comprehension impairment and, as a result, the posterior temporal lobe is assumed to be critical to semantic cognition. This conclusion is potentially confused by (a) the existence of patient groups with semantic impairment following damage to other brain regions (semantic dementia and…

This paper investigates the cognitive processes underlying picture naming and auditory word repetition. In the two-step model of lexical access, both the semantic and phonological steps are involved in naming, but the former has no role in repetition. Assuming recognition of the to-be-repeated word, repetition could consist of retrieving the…

This study investigates the temporal resolution capacities of the central-auditory system in a subject (NP) suffering from repetition conduction aphasia. More specifically, the patient was asked to detect brief gaps between two stretches of broadband noise (gap detection task) and to evaluate the duration of two biphasic (WN-3) continuous noise…

Focal brain lesions are assumed to produce language deficits by two basic mechanisms: local cortical dysfunction at the lesion site, and remote cortical dysfunction due to disruption of the transfer and integration of information between connected brain regions. However, functional imaging studies investigating language outcome after aphasic…

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…

Lesion studies have demonstrated impairments of specific types of phonological processes. However, results from neuropsychological studies of speech sound processing have been inconclusive as to the role of specific brain regions because of a lack of a one-to-one correspondence between behavioural patterns and lesion location. Functional…