Approximately one-third of stroke victims in the United States suffer from aphasia, a disorder that affects the ability to use and/or understand language. There is some spontaneous recovery of language skills in the early stages of post-stroke aphasia, but the disorder rarely resolves completely, and behavioral therapy plays an important role in aphasia management. Essentially all individuals with aphasia suffer from anomia, or decreased word-finding skills, so this impairment is a common target of aphasia therapy; however, the specific causes of anomia vary across individuals and patients' therapy outcomes can be unpredictable or inconsistent. In designing model-based treatment for anomia, clinicians rely on out loud language abilities to understand the underlying deficit, but this metho is often unreliable. This study aims to investigate whether individuals with aphasia can provide meaningful information about their internal experience of word-finding difficulty, to help clarify the causes of anomia and potentially guide treatment approaches for this pervasive deficit. Individuals with aphasia commonly report a mismatch between their inner speech (IS) and out loud naming ability, often stating, I know it but I can't say it or, more specifically, I can't ay it out loud, but it sounds right in my head. Accordingly, the main hypothesis for this proposal is that many people with anomia are aware of where their inability to find a word arises and can accurately report it, when given the opportunity to do so. Preliminary questionnaire data indicate that many individuals with aphasia do report successful IS during overt anomia, reflecting a feeling of intact access to the phonological representation despite impaired post-lexical output processes. Pilot data from preliminary voxel-based lesion-symptom mapping (VLSM) analyses indicate that these individuals have lesions in the anterior brain regions that subserve spoken output. Furthermore, on behavioral testing, these patients demonstrate poorer phonological output skills than individuals who do not report successful IS during overt anomia.
In Aim 1 of the proposed study, a questionnaire will be used to provide a large number of individuals with aphasia a structured opportunity to describe their own experience of anomia. Subjects will also participate in behavioral language testing and structural imaging, to confirm the preliminary correlations found between self-reported IS, phonological output skills, and lesion location.
In Aim 2, a subset of subjects will participate in a crossover treatment study comparing two behavioral treatments for naming, to examine whether self-report of IS predicts therapeutic success. These two treatments target different processes involved in naming and have been independently validated in previous literature but never directly compared. The findings from the proposed research aims will help to clarify the cognitive mechanisms underlying anomia and may establish self-reported IS as a feasible complement (or alternative) to traditional methods in model-based anomia treatment, potentially generating greater therapeutic success.
Approximately one-third of stroke victims in the United States suffer from aphasia, a disorder that affects the ability to use and/or understand language. All individuals with aphasia suffer from decreased word-finding abilities (anomia), but the cognitive mechanisms underlying this deficit are not fully understood, and there are no guaranteed treatment methods. This study aims to investigate whether individuals with aphasia can report meaningful information about their experience of anomia, which can help clarify the variability of word-finding deficits in aphasia and, in turn, guide the selection of treatment approaches for improving this essential language function.
| Fama, Mackenzie E; Hayward, William; Snider, Sarah F et al. (2017) Subjective experience of inner speech in aphasia: Preliminary behavioral relationships and neural correlates. Brain Lang 164:32-42 |
| Fama, Mackenzie E; Baron, Christine R; Hatfield, Brooke et al. (2016) Group therapy as a social context for aphasia recovery: a pilot, observational study in an acute rehabilitation hospital. Top Stroke Rehabil 23:276-83 |
