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Behavioral And Neurophysiological Measures Of Speech Auditory Feedback Processing Impairment In Left Hemisphere Stroke, Stacey Sangtian

Theses and Dissertations

The purpose of this study was to identify behavioral and neural correlates of impaired speech auditory feedback processing in people with a history of left-hemisphere stroke (LHS). To do this, we used the altered auditory feedback (AAF) paradigm to externally induce speech errors by randomly shifting the pitch frequency of the online auditory feedback up or down at ±100 cents in 38 LHS and 27 neurologically intact control participants under two experimental conditions: 1) active vocalizations of a steady speech vowel sound “ah,” and 2) passive listening to the playback of the same self-produced vocalizations. Randomized control trials were included …

Transcranial Alternating Current Stimulation As An Adjuvant For Nonfluent Aphasia Therapy: A Proof-Of-Concept Study, Lynsey Mcgrath Keator

Theses and Dissertations

Identifying effective and efficient rehabilitation tools is crucial to improve language outcomes for persons living with chronic aphasia. Speech entrainment has proved to be particularly successful in improving speech output in nonfluent aphasia. It is hypothesized that, for patients with aberrant oscillatory synchronization between anterior and posterior language regions of the left hemisphere, speech entrainment may act as an external gaiting mechanism to bolster an impaired efference copy and improve synchrony between these regions. Theoretical and empirical evidence supports this idea that speech production relies on anterior-posterior connectivity in the left hemisphere.

Transcranial alternating current stimulation (tACS) delivers low, periodically-alternating …