ASU Electronic Theses and Dissertations
This collection includes most of the ASU Theses and Dissertations from 2011 to present. ASU Theses and Dissertations are available in downloadable PDF format; however, a small percentage of items are under embargo. Information about the dissertations/theses includes degree information, committee members, an abstract, supporting data or media.
In addition to the electronic theses found in the ASU Digital Repository, ASU Theses and Dissertations can be found in the ASU Library Catalog.
Dissertations and Theses granted by Arizona State University are archived and made available through a joint effort of the ASU Graduate College and the ASU Libraries. For more information or questions about this collection contact or visit the Digital Repository ETD Library Guide or contact the ASU Graduate College at gradformat@asu.edu.
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Description
The activation of the primary motor cortex (M1) is common in speech perception tasks that involve difficult listening conditions. Although the challenge of recognizing and discriminating non-native speech sounds appears to be an instantiation of listening under difficult circumstances, it is still unknown if M1 recruitment is facilitatory of second language speech perception. The purpose of this study was to investigate the role of M1 associated with speech motor centers in processing acoustic inputs in the native (L1) and second language (L2), using repetitive Transcranial Magnetic Stimulation (rTMS) to selectively alter neural activity in M1. Thirty-six healthy English/Spanish bilingual subjects participated in the experiment. The performance on a listening word-to-picture matching task was measured before and after real- and sham-rTMS to the orbicularis oris (lip muscle) associated M1. Vowel Space Area (VSA) obtained from recordings of participants reading a passage in L2 before and after real-rTMS, was calculated to determine its utility as an rTMS aftereffect measure. There was high variability in the aftereffect of the rTMS protocol to the lip muscle among the participants. Approximately 50% of participants showed an inhibitory effect of rTMS, evidenced by smaller motor evoked potentials (MEPs) area, whereas the other 50% had a facilitatory effect, with larger MEPs. This suggests that rTMS has a complex influence on M1 excitability, and relying on grand-average results can obscure important individual differences in rTMS physiological and functional outcomes. Evidence of motor support to word recognition in the L2 was found. Participants showing an inhibitory aftereffect of rTMS on M1 produced slower and less accurate responses in the L2 task, whereas those showing a facilitatory aftereffect of rTMS on M1 produced more accurate responses in L2. In contrast, no effect of rTMS was found on the L1, where accuracy and speed were very similar after sham- and real-rTMS. The L2 VSA measure was indicative of the aftereffect of rTMS to M1 associated with speech production, supporting its utility as an rTMS aftereffect measure. This result revealed an interesting and novel relation between cerebral motor cortex activation and speech measures.
ContributorsBarragan, Beatriz (Author) / Liss, Julie (Thesis advisor) / Berisha, Visar (Committee member) / Rogalsky, Corianne (Committee member) / Restrepo, Adelaida (Committee member) / Arizona State University (Publisher)
Created2018
Description
Repetitive practice of functional movement patterns during motor rehabilitation are known to drive learning (or relearning) of novel motor skills, but the learning process is highly variable between individuals such that responsiveness to task-specific training is often patient-specific. A number of neuroimaging and neurophysiological methods have been proposed to better predict a patient’s responsiveness to a given type or dose of motor therapy. However, these methods are often time- and resource-intensive, and yield results that are not readily interpretable by clinicians. In contrast, standardized visuospatial tests may offer a more feasible solution. The work presented in this dissertation demonstrate that a clinical paper-and-pencil test of visuospatial function may improve predictive models of motor skill learning in older adults and individuals with stroke pathology. To further our understanding of the neuroanatomical correlates underlying this behavioral relationship, I collected diffusion-weighted magnetic resonance images from 19 nondemented older adults to determine if diffusion characteristics of white matter tracts explain shared variance in delayed visuospatial memory test scores and motor skill learning. Consistent with previous work, results indicated that the structural integrity of regions with the bilateral anterior thalamic radiations, corticospinal tracts, and superior longitudinal fasciculi are related to delayed visuospatial memory performance and one-week skill retention. Overall, results of this dissertation suggest that incorporating a clinical paper-and-pencil test of delayed visuospatial memory may prognose motor rehabilitation outcomes and support that personalized variables should be considered in standards of care. Moreover, regions within specific white matter tracts may underlie this behavioral relationship and future work should investigate these regions as potential targets for therapeutic intervention.
ContributorsLingo VanGilder, Jennapher (Author) / Schaefer, Sydney Y (Thesis advisor) / Santello, Marco (Committee member) / Buneo, Christopher (Committee member) / Rogalsky, Corianne (Committee member) / Duff, Kevin (Committee member) / Arizona State University (Publisher)
Created2021
Description
Individuals with autism spectrum disorder (ASD) are known to show impairments in various domains of executive function (EF) such as behavioral flexibility or inhibitory control. Research suggests that EF impairment in adults with ASD may relate to ASD core symptoms, restrictive behaviors and social communication deficits. Mindfulness-based stress reduction (MBSR) has shown promise for improving EF abilities in neurotypical adults, but research has not explored its efficacy or neural mechanisms in adults with ASD. This pilot study examines the effects of an 8-week MBSR intervention on self-report measures of EF and resting-state functional connectivity in a sample of adults with ASD. Fifty-four participants were assigned either to an MBSR group (n = 29) or a social support group (n = 25). Executive function was measured using the BRIEF-2 before and after the intervention for the twenty-seven participants in the second cohort. MBSR-specific improvements in EF were found for BRIEF measures of initiation, inhibition, and working-memory. Resting-state fMRI data was analyzed using independent component analysis (ICA), and group by time resting-state functional connectivity differences were observed between the cerebellar network and frontal regions including the right frontal pole (rFP), medial frontal cortex (MFC) and left and right superior frontal gyri (SFG). The MBSR group showed increases in functional connectivity between the cerebellum and EF regions which correlated with improvements in BRIEF-2 measures. These findings suggest that MBSR may improve EF domains in adults with ASD, and that increases in functional connectivity between the cerebellum and frontal regions while at rest may be a mechanism for such improvements.
ContributorsGuerithault, Nicolas (Author) / Braden, B. Blair (Thesis advisor) / Rogalsky, Corianne (Committee member) / Dixon, Maria (Committee member) / Arizona State University (Publisher)
Created2021
Description
ABSTRACTAutism spectrum disorder (ASD) is a neurodevelopmental condition associated with social communication challenges and restrictive and repetitive behaviors [2]. Despite known lifelong challenges, understanding of cognitive and brain aging with ASD is lacking. Middle-aged adults with ASD have a higher chance of developing Alzheimer’s disease (Alz) and other dementias compared to neurotypical (NT) adults [12].
Apolipoprotein E (APOE) is a lipid transport protein involved in neuronal repair and cholesterol transport and is the strongest genetic risk factor for Alz [22]. Others demonstrated that individuals with ASD are more likely to carry the APOE ε4-allele [21]. This study aimed to determine if the APOE ε4-allele negatively impacts verbal learning and memory in ASD compared to NT adults.
Participants were intellectually able 76 middle-age and older adults (MA+) between the ages of 40-71, including 35 with ASD [mean age=53.06 (±8.91)] and 41 NT adults [mean age=53.90 (±8.44)]. APOE allelic distribution was determined from salivary samples via polymerase chain reaction amplification and genotyped on a tapestation. The Auditory Verbal Learning Test (AVLT) variables were short-term memory, long-term memory, and total learning.
There was a main effect of APOE ε4 for short-term memory and verbal learning, with ε4 carriers performing worse across diagnosis groups. For verbal learning, sex was a significant predictor. So, exploratory analyses separating diagnosis groups by sex were conducted. Only males with ASD were found to be carrying APOE ε4 associated with reduced verbal learning (p=0.02). Finally, the APOE ε4-allele did not significantly affect the participants’ long-term memory.
These findings suggest that the APOE ε4-allele negatively impacts short-term memory and verbal learning in MA+ adults, and that autistic men may be particularly vulnerable to the effects of APOE ε4 on verbal learning. This study is the first to incorporate ASD in APOE’s association with cognition and investigate how sex differences impact memory function. Future research is needed to replicate these findings using a larger sample size to further understand how the ε4-allele affects memory function trajectories in MA+ ASD as they grow older.
ContributorsAl-Hassan, Lamees (Author) / Braden, Blair (Thesis advisor) / Lewis, Candace (Committee member) / Rogalsky, Corianne (Committee member) / Arizona State University (Publisher)
Created2023
Description
Diffusion weighted imaging utilizes magnetic resonance imaging to capture white matter tracts in the brain. Many studies have utilized this technique to measure white matter structures looking for evidence of anatomical and physiological differences in Autism Spectrum Disorder (ASD). Parkinsonian-like symptoms have been documented and self-reported in aging autistic individuals, opening up questions about a possible link between ASD and an increased risk of Parkinson’s Disease. Utilizing MRtrix3, an image processing proof-of-concept pipeline was developed for the Autism and Brain Aging (ABA) lab to generate and visualize the brain’s structural connectivity network in these populations of interest. The pipeline provides the opportunity for white matter tractography analysis in the lab’s Aging in Autism study.
ContributorsFeldman, Leslie (Author) / Ofori, Edward (Thesis advisor) / Braden, Blair (Committee member) / Rogalsky, Corianne (Committee member) / Arizona State University (Publisher)
Created2023
Description
Autism shows a pronounced and replicable sex bias with approximately three-to-four males diagnosed for every one female. Sex-related biology is thought to play a role in the sex bias, such that female biology may be protective and/or male biology may increase vulnerability to autism in the context of similar genetic risk. Beyond etiology, sex-related biology has also been implicated in lifespan risk for health and psychiatric conditions that show common co-morbidity in autism. Thus, understanding how sex-related biology impacts autism etiology and progression has important implications for prognosis and treatment. Neuroimaging offers a powerful tool for in-vivo characterization of brain-based sex differences in autism, especially given emerging efforts to develop large, well-characterized longitudinal samples. To date, however, neuroimaging studies have shown mixed and inconsistent findings, which remain challenging to integrate in the broader literature context. In a recent systematic review of neuroimaging studies of typical sex differences, few to no replicable effects were found beyond brain size, suggesting the brain is not “sexually dimorphic.” Instead, it is argued that the brain is a “mosaic” of features from various sources, including masculine and feminine biological processes as well as individual genetics and environment. Thus, designing neuroimaging studies that are sensitive to brain-based sex differences in autism likely requires careful study design and analytical method selection. Through a series of studies, the overarching dissertation aim was to identify optimal methods for characterizing neuroimaging-based sex differences in autism and to test these methods in preliminary samples. Study 1 comprised a systematic review of studies examining neuroimaging-based sex differences in autism with the aim of identifying optimal study designs, neuroimaging modalities, and analytical methods. Study 2 focused on examining the sensitivity of a connectome-wide approach to identify functional connectivity hubs underlying sex-biased behavior associated with autism (e.g., camouflaging). Study 3 used a connectome-wide functional connectivity approach to characterize sex differences in longitudinal changes associated with autistic traits vs. categorical diagnosis. These studies suggest that optimizing study design and methods improves identification of biologically plausible and clinically meaningful brain sex differences in autism. The relevance of findings to etiology and prognosis are discussed.
ContributorsWalsh, Melissa (Author) / Braden, B. Blair (Thesis advisor) / Azuma, Tamiko (Committee member) / Rogalsky, Corianne (Committee member) / Arizona State University (Publisher)
Created2022
Description
Objective: Previous studies have observed that adults with dyslexia display a reduced N1 gating when exposed to repetitive stimuli. Robust gating is associated with the ability to recognize familiar stimuli and identify the stimuli that will need novel memory representations formed. This study investigates if the mismatch negativity component in electroencephalographic-produced Event-Related Potentials (ERPs) is affected as well by diminished memory forming in adults with dyslexia. Additionally, signal/ noise processing for auditory-based memory recollection and thus word learning is explored. Methods: Nineteen adults with dyslexia and 18 adult controls participated in a classic auditory oddball electroencephalographic experiment here referred to as DIFF, to indicate that the tones differed in frequency, while incorporating a decision-making task that signified participant tonal discrimination. Mismatch Negativity (MMN) amplitudes (AMPs) and latencies were collected from ERPs. Behavioral data consisting of reaction time (RT) and accuracy (ACC) of tone choice were documented.
Results: Group differences for accuracy and reaction time in the DIFF task were highly significant. The dyslexic group produced longer reaction times and with less accuracy than the control group. The Mismatch Negativity amplitude and latency collected did not differ significantly between groups, however, correlations to other variables obtained from similar studies consisting of the same participant group were observed. Linear regression models indicated predictions for accuracy and reaction time results based upon WID scores (Word Identification Test) and SWE scores (Sight Word Efficiency) respectfully.
Conclusions: Neural processing speed and the ability to form permanent memory representations of auditory sound bites for retrieval is dampened in dyslexic populations.
Significance: To better illuminate and understand the neural mechanisms of dyslexia, specifically auditory processing, with the goal of improving outcomes in individuals with dyslexia through more efficient therapy treatment options.
ContributorsAbrams, Gabrielle Renee (Author) / Peter, Beate (Thesis advisor) / Rogalsky, Corianne (Committee member) / Rao, Aparna (Committee member) / Arizona State University (Publisher)
Created2022
Description
Stroke is the leading cause of long-term disability in the U.S., with up to 60% of strokescausing speech loss. Individuals with severe stroke, who require the most frequent, intense speech therapy, often cannot adhere to treatments due to high cost and low success rates. Therefore, the ability to make functionally significant changes in individuals with severe post- stroke aphasia remains a key challenge for the rehabilitation community. This dissertation aimed to evaluate the efficacy of Startle Adjuvant Rehabilitation Therapy (START), a tele-enabled, low- cost treatment, to improve quality of life and speech in individuals with severe-to-moderate stroke. START is the exposure to startling acoustic stimuli during practice of motor tasks in individuals with stroke. START increases the speed and intensity of practice in severely impaired post-stroke reaching, with START eliciting muscle activity 2-3 times higher than maximum voluntary contraction. Voluntary reaching distance, onset, and final accuracy increased after a session of START, suggesting a rehabilitative effect. However, START has not been evaluated during impaired speech. The objective of this study is to determine if impaired speech can be elicited by startling acoustic stimuli, and if three days of START training can enhance clinical measures of moderate to severe post-stroke aphasia and apraxia of speech. This dissertation evaluates START in 42 individuals with post-stroke speech impairment via telehealth in a Phase 0 clinical trial. Results suggest that impaired speech can be elicited by startling acoustic stimuli and that START benefits individuals with severe-to-moderate post-stroke impairments in both linguistic and motor speech domains. This fills an important gap in aphasia care, as many speech therapies remain ineffective and financially inaccessible for patients with severe deficits. START is effective, remotely delivered, and may likely serve as an affordable adjuvant to traditional therapy for those that have poor access to quality care.
ContributorsSwann, Zoe Elisabeth (Author) / Honeycutt, Claire F (Thesis advisor) / Daliri, Ayoub (Committee member) / Rogalsky, Corianne (Committee member) / Liss, Julie (Committee member) / Schaefer, Sydney (Committee member) / Arizona State University (Publisher)
Created2022
Description
The label-feedback hypothesis (Lupyan, 2007, 2012) proposes that language modulates low- and high-level visual processing, such as priming visual object perception. Lupyan and Swingley (2012) found that repeating target names facilitates visual search, reducing response times and increasing accuracy. Hebert, Goldinger, and Walenchok (under review) used a modified design to replicate and extend this finding, and concluded that speaking modulates visual search via template integrity. The current series of experiments 1) replicated the work of Hebert et al. with audio stimuli played through headphones instead of self-directed speech, 2) examined the label feedback effect under conditions of varying object clarity, and 3) explored whether the relative prevalence of a target’s audio label might modulate the label feedback effect (as in the low prevalence effect; Wolfe, Horowitz, & Kenner, 2005). Paradigms utilized both traditional spatial visual search and repeated serial visual presentation (RSVP). Results substantiated those found in previous studies—hearing target names improved performance, even (and sometimes especially) when conditions were difficult or noisy, and the relative prevalence of a target’s audio label strongly impacted its perception. The mechanisms of the label feedback effect––namely, priming and target template integrity––are explored.
ContributorsHebert, Katherine P (Author) / Goldinger, Stephen D (Thesis advisor) / Rogalsky, Corianne (Committee member) / McClure, Samuel M. (Committee member) / Benitez, Viridiana (Committee member) / Arizona State University (Publisher)
Created2019
Description
The ability to detect and correct errors during and after speech production is essential for maintaining accuracy and avoiding disruption in communication. Thus, it is
crucial to understand the basic mechanisms underlying how the speech-motor system
evaluates different errors and correspondingly corrects them. This study aims to explore
the impact of three different features of errors, introduced by formant perturbations, on
corrective and adaptive responses: (1) magnitude of errors, (2) direction of errors, and (3)
extent of exposure to errors. Participants were asked to produce the vowel /ε/ in the
context of consonant-vowel-consonant words. Participant-specific formant perturbations
were applied for three magnitudes of 0.5, 1, 1.5 along the /ε-æ/ line in two directions of
simultaneous F1-F2 shift (i.e., shift in the ε-æ direction) and shift to outside the vowel
space. Perturbations were applied randomly in a compensation paradigm, so each
perturbed trial was preceded and succeeded by several unperturbed trials. It was observed
that (1) corrective and adaptive responses were larger for larger magnitude errors, (2)
corrective and adaptive responses were larger for errors in the /ε-æ/ direction, (3)
corrective and adaptive responses were generally in the /ε-ɪ/ direction regardless of
perturbation direction and magnitude, (4) corrective responses were larger for
perturbations in the earlier trials of the experiment.
ContributorsSreedhar, Anuradha Jyothi (Author) / Daliri, Ayoub (Thesis advisor) / Rogalsky, Corianne (Committee member) / Zhou, Yi (Committee member) / Arizona State University (Publisher)
Created2024