The Unfolding of Cognitive Effort During Sentence Processing: Pupillometric Evidence From People With and Without Aphasia.

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), pupillometry may be uniquely suited to explore those relationships. The purpose of this study was to examine arousal and the time course of the allocation of cognitive effort related to sentence processing in people with and without aphasia. METHOD: Nineteen PWA and age- and education-matched control participants listened to relatively easy (subject-relative) and relatively difficult (object-relative) sentences and were required to answer occasional comprehension questions. Tonic and phasic pupillary responses were used to index arousal and the unfolding of cognitive effort, respectively, while sentences were processed. Group differences in tonic and phasic responses were examined. RESULTS: Group differences were observed for both tonic and phasic responses. PWA exhibited greater overall arousal throughout the task compared with controls, as evidenced by larger tonic pupil responses. Controls exhibited more effort (greater phasic responses) for difficult compared with easy sentences; PWA did not. Group differences in phasic responses were apparent during end-of-sentence and postsentence time windows. CONCLUSIONS: Results indicate that the attentional state of PWA in this study was not consistently supportive of adequate task engagement. PWA in our sample may have relatively limited attentional capacity or may have challenges with allocating existing capacity in ways that support adequate task engagement and performance. This work adds to the body of evidence supporting the validity of pupillometric tasks for the study of aphasia and contributes to a better understanding of the nature of language deficits in aphasia. Supplemental Material https://doi.org/10.23641/asha.16959376.

Expecting Questions Modulates Cognitive Effort in a Syntactic Processing Task: Evidence From Pupillometry.

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 cognition and language in people with and without aphasia. Interpretation of pupillary responses is complex. This study was designed as a stepping-stone for future pupillometric studies involving people with aphasia. Asking comprehension questions is common in language processing research involving people with and without aphasia. However, the influence of comprehension questions on pupillometric indices of task engagement (tonic responses) and cognitive effort (task-evoked responses of the pupil [TERPs]) is unknown. We tested whether asking comprehension questions influenced pupillometric results of adults without aphasia during a syntactic processing task. Method Forty adults without aphasia listened to easy (canonical) and difficult (noncanonical) sentences in two conditions: one that contained an explicit comprehension task (question condition) and one that did not (no-question condition). The influence of condition and canonicity on pupillary responses was examined. Results The influence of canonicity was only significant in the question condition: TERPs for difficult sentences were larger than TERPs for easy sentences. Tonic responses did not differ between conditions. Conclusions Although participants had similar levels of attentiveness in both conditions, increases in indices of cognitive effort during syntactic processing were significant only when participants expected comprehension questions. Results contribute to a body of evidence indicating the importance of task design and careful linguistic stimulus control when using pupillometry to study language processing. Supplemental Material https://doi.org/10.23641/asha.13480368.

Validity of an eyetracking method for capturing auditory-visual cross-format semantic priming.

INTRODUCTION: Semantic priming paradigms are important for understanding lexical-semantic processing and the nature of linguistic deficits accompanying language performance in neurologically impaired individuals such as people with aphasia. Reaction-time-(RT)-based traditional semantic priming tasks entail potential confounds, especially problematic when applied to people with aphasia, who may have concomitant neurocognitive challenges that limit task performance. Some of these confounds include requirements of following complex instructions, making metalinguistic judgments, and using speech or limb-based motor actions to indicate overt responses. Eyetracking methods have great potential for avoiding some of these confounds. We tested the validity of an eyetracking method in capturing semantic priming in an auditory-visual cross-format priming paradigm (auditory word prime-visual image target). METHOD: A total of 72 neurologically unimpaired adults participated in two phases: a stimulus development phase using traditional priming (n = 32) and an experimental eyetracking phase (n = 40). Each phase included two conditions, representing distinct levels of prime-target semantic relatedness: unrelated and related. Mean RT data from the traditional priming (stimuli development) phase guided image selection for the eyetracking experiment. Eyetracking indices of fixation duration and latency of fixation were recorded to capture semantic priming in the eyetracking experiment. RESULTS: Eye fixation data indicated that images related to auditory primes were attended to earlier and attracted significantly greater visual attention than unrelated images. These results mirrored RT data from the traditional priming method, which showed faster RT latencies and more accurate naming performance for related images than for unrelated images. CONCLUSIONS: Results support the validity of eyetracking indices of semantic priming and offer a robust testing protocol for future studies in this line of research. Current clinical relevance for people with aphasia is highlighted. Further empirical testing of the psychometric properties of the eyetracking measures in various semantic priming contexts is recommended.

Where Children With ADHD Direct Visual Attention During Emotion Knowledge Tasks: Relationships to Accuracy, Response Time, and ADHD Symptoms.

OBJECTIVE: Inattention may contribute to emotion recognition deficits in children with ADHD. In the current study, we compared the viewing patterns for emotion stimuli between children with and without ADHD and examined the relationship between viewing patterns, emotion knowledge accuracy, response time, and ADHD symptoms. METHOD: Eye-tracking technology recorded viewing patterns for emotion stimuli among 45 children (60% male; control n = 26, ADHD n = 19). RESULTS: Overall, viewing patterns of children with and without ADHD were strikingly similar; however, small to large effect sizes (Cohen's d = -0.73 to 0.93) across emotions suggest that, for some emotions, children with ADHD spend less time viewing relevant areas of images and take longer to respond (i.e., detect an emotion) compared with children without ADHD. CONCLUSION: Children with ADHD view some emotions differently from children without ADHD. The results provide an important foundation for additional work in this area.

More Than the Verbal Stimulus Matters: Visual Attention in Language Assessment for People With Aphasia Using Multiple-Choice Image Displays.

Purpose: Language comprehension in people with aphasia (PWA) is frequently evaluated using multiple-choice displays: PWA are asked to choose the image that best corresponds to the verbal stimulus in a display. When a nontarget image is selected, comprehension failure is assumed. However, stimulus-driven factors unrelated to linguistic comprehension may influence performance. In this study we explore the influence of physical image characteristics of multiple-choice image displays on visual attention allocation by PWA. Method: Eye fixations of 41 PWA were recorded while they viewed 40 multiple-choice image sets presented with and without verbal stimuli. Within each display, 3 images (majority images) were the same and 1 (singleton image) differed in terms of 1 image characteristic. The mean proportion of fixation duration (PFD) allocated across majority images was compared against the PFD allocated to singleton images. Results: PWA allocated significantly greater PFD to the singleton than to the majority images in both nonverbal and verbal conditions. Those with greater severity of comprehension deficits allocated greater PFD to nontarget singleton images in the verbal condition. Conclusion: When using tasks that rely on multiple-choice displays and verbal stimuli, one cannot assume that verbal stimuli will override the effect of visual-stimulus characteristics.

Let's call it "aphasia": Rationales for eliminating the term "dysphasia".

Health professionals, researchers, and policy makers often consider the two terms aphasia and dysphasia to be synonymous. The aim of this article is to argue the merits of the exclusive use of the term aphasia and present a strategy for creating change through institutions such as the WHO-ICD. Our contention is that one term avoids confusion, speech-language pathologists prefer aphasia, scholarly publications indicate a preference for the term aphasia, stroke clinical guidelines indicate a preference for the term aphasia, consumer organizations use the title aphasia in their name and on their websites, and languages other than English use a term similar to aphasia. The use of the term dysphasia in the broader medical community may stem from the two terms being used interchangeably in the ICD10. Aphasia United http://www.shrs.uq.edu.au/aphasiaunited , an international movement for uniting the voice of all stakeholders in aphasia within an international context, will seek to eliminate the use of the term dysphasia.

A Novel Pupillometric Method for Indexing Word Difficulty in Individuals With and Without Aphasia.

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 pupil dilation and constriction during a cognitive task), yet pupillometry has not been implemented in studies including PWA. In the present study, we tested a novel method for indexing cognitive effort during linguistic processing in people with and without aphasia. METHOD: Forty control participants and 39 PWA listened to semantically easy and difficult single nouns and looked at images while their pupillary responses were monitored. Mean pupil dilation in response to easy versus difficult nouns was calculated to index cognitive effort. RESULTS: Larger mean pupil dilation values were obtained for difficult compared with easy nouns for both groups. CONCLUSION: Results provide preliminary evidence that pupillometry can be used to index cognitive effort during linguistic processing of single nouns in people with and without aphasia. Methods for indexing cognitive effort will be a valuable addition to existing assessment methods. Suggestions for further research are offered.

A novel eye-tracking method to assess attention allocation in individuals with and without aphasia using a dual-task paradigm.

UNLABELLED: Numerous authors report that people with aphasia have greater difficulty allocating attention than people without neurological disorders. Studying how attention deficits contribute to language deficits is important. However, existing methods for indexing attention allocation in people with aphasia pose serious methodological challenges. Eye-tracking methods have great potential to address such challenges. We developed and assessed the validity of a new dual-task method incorporating eye tracking to assess attention allocation. Twenty-six adults with aphasia and 33 control participants completed auditory sentence comprehension and visual search tasks. To test whether the new method validly indexes well-documented patterns in attention allocation, demands were manipulated by varying task complexity in single- and dual-task conditions. Differences in attention allocation were indexed via eye-tracking measures. For all participants significant increases in attention allocation demands were observed from single- to dual-task conditions and from simple to complex stimuli. Individuals with aphasia had greater difficulty allocating attention with greater task demands. Relationships between eye-tracking indices of comprehension during single and dual tasks and standardized testing were examined. Results support the validity of the novel eye-tracking method for assessing attention allocation in people with and without aphasia. Clinical and research implications are discussed. LEARNING OUTCOMES: Readers will be able to: (1) summarize the nature of dual-task paradigms, (2) identify shortcomings of existing dual-task measures of attention allocation for application to people with aphasia, (3) describe how eye-tracking measures may be recorded and analyzed to reflect differences in attention allocation across conditions, and (4) summarize potential clinical applications for eye-tracking measures of attention allocation.

A new modified listening span task to enhance validity of working memory assessment for people with and without aphasia.

UNLABELLED: Deficits in working memory (WM) are an important subset of cognitive processing deficits associated with aphasia. However, there are serious limitations to research on WM in aphasia largely due to the lack of an established valid measure of WM impairment for this population. The aim of the current study was to address shortcomings of previous measures by developing and empirically evaluating a novel WM task with a sentence-picture matching processing component designed to circumvent confounds inherent in existing measures of WM in aphasia. The novel WM task was presented to persons with (n=27) and without (n=33) aphasia. Results demonstrated high concurrent validity of a novel WM task. Individuals with aphasia performed significantly worse on all conditions of the WM task compared to individuals without aphasia. Different patterns of performance across conditions were observed for the two groups. Additionally, WM capacity was significantly related to auditory comprehension abilities in individuals with mild aphasia but not those with moderate aphasia. Strengths of the novel WM task are that it allows for differential control for length versus complexity of verbal stimuli and indexing of the relative influence of each, minimizes metalinguistic requirements, enables control for complexity of processing components, allows participants to respond with simple gestures or verbally, and eliminates reading requirements. Results support the feasibility and validity of using a novel task to assess WM in individuals with and without aphasia. LEARNING OUTCOMES: Readers will be able to (1) discuss the limitations of current working memory measures for individuals with aphasia; (2) describe how task design features of a new working memory task for people with aphasia address shortcomings of existing measures; (3) summarize the evidence supporting the validity of the novel working memory task.

A tutorial on aphasia test development in any language: Key substantive and psychometric considerations.

BACKGROUND: There are a limited number of aphasia language tests in the majority of the world's commonly spoken languages. Furthermore, few aphasia tests in languages other than English have been standardized and normed, and few have supportive psychometric data pertaining to reliability and validity. The lack of standardized assessment tools across many of the world's languages poses serious challenges to clinical practice and research in aphasia. AIMS: The current review addresses this lack of assessment tools by providing conceptual and statistical guidance for the development of aphasia assessment tools and establishment of their psychometric properties. MAIN CONTRIBUTION: A list of aphasia tests in the 20 most widely spoken languages is included. The pitfalls of translating an existing test into a new language versus creating a new test are outlined. Factors to consider in determining test content are discussed. Further, a description of test items corresponding to different language functions is provided, with special emphasis on implementing important controls in test design. Next, a broad review of principal psychometric properties relevant to aphasia tests is presented, with specific statistical guidance for establishing psychometric properties of standardized assessment tools. CONCLUSIONS: This article may be used to help guide future work on developing, standardizing and validating aphasia language tests. The considerations discussed are also applicable to the development of standardized tests of other cognitive functions.

Eighteen years on: What next for the PALPA?

The Psycholinguistic Assessments of Language Processing Abilities (PALPA) is a battery of tests designed to assess language processing abilities in individuals with acquired aphasia. Published in 1992, the battery was well-received by both clinicians and researchers, yet no revised version has been published to date. In this paper, we examine contemporary usage of the PALPA in both clinical and research settings, to inform decisions regarding future developments of the resource. First, we carried out a literature search to identify all published papers that have cited the PALPA since 2003, and compared our findings to those from an earlier search covering the period from 1991 to 2002. Second, we created an online survey that examined current usage of the PALPA in both clinicians and researchers. Our findings suggest the PALPA continues to be a well-used tool in both clinical and research settings, but could benefit from some improvements in its content and presentation. Further, there are time constraints in administering the PALPA, indicating an additional component for general-screening purposes would be a welcome extension to the battery.

Validity of eye movement methods and indices for capturing semantic (associative) priming effects.

PURPOSE: The purpose of this investigation was to evaluate the usefulness of eye movement methods and indices as a tool for studying priming effects by verifying whether eye movement indices capture semantic (associative) priming effects in a visual cross-format (written word to semantically related picture) priming paradigm. METHOD: In the stimuli development phase, words semantically associated to an array of pictures were generated based on 100 adults' association data for each picture. A total of 40 additional adult participants with normal language engaged in an eye movement experiment using the word-picture associations developed previously. The design consisted of each prime preceding a display showing 1 high-association (target) and 2 low-association (nontarget) images. Fixation durations, locations, and latencies were measured. RESULTS: Images semantically related to the prime showed greater fixation durations and shorter latencies compared to nontargets. Eye movement and traditional reaction time measures were found to correlate for some of the experimental conditions. CONCLUSIONS: Results showed that free-viewing eye movement measures, in which participants are not instructed to look at anything in particular, hold promise as valid indicators of priming effects. Further research in this area will help to advance language-processing theories in individuals with and without language impairment.

Comparison of alternatives to multidimensional scoring in the assessment of language comprehension in aphasia.

PURPOSE: Multidimensional scoring methods yield valuable information about communication abilities. However, issues of training demands for valid and reliable scoring, especially in current service delivery contexts, may preclude common usage. Alternatives to multidimensional scoring were investigated in a sample of adults with aphasia. METHOD: One alternative method involved modified multidimensional scoring; the others incorporated correct/incorrect scoring. The scores for the 3 alternative methods were derived from the scores obtained using the traditional multidimensional method. Revised Token Test scores obtained using the traditional multidimensional method were collected from 10 participants with aphasia. These scores were manipulated to yield 3 additional sets of scores corresponding to the alternative methods. RESULTS: There were no significant differences between the traditional multidimensional method and 1 of the correct/incorrect methods. Significant differences were found between traditional multidimensional scoring and each of the other 2 methods. CONCLUSIONS: The study findings suggest that simpler scoring systems might yield similar data to traditional multidimensional scoring. If simpler alternative methods yield similar results, using alternative scoring methods with published tests based on multidimensional scoring will help expand their use in everyday clinical practice.