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Description
With a growing number of adults with autism spectrum disorder (ASD), more and more research has been conducted on majority male cohorts with ASD from young, adolescence, and some older age. Currently, males make up the majority of individuals diagnosed with ASD, however, recent research states that the gender gap is closing due to more advanced screening and a better understanding of how females with ASD present their symptoms. Little research has been published on the neurocognitive differences that exist between older adults with ASD compared to neurotypical (NT) counterparts, and nothing has specifically addressed older women with ASD. This study utilized neuroimaging and neuropsychological tests to examine differences between diagnosis and sex of four distinct groups: older men with ASD, older women with ASD, older NT men, and older NT women. In each group, hippocampal size (via FreeSurfer) was analyzed for differences as well as correlations with neuropsychological tests. Participants (ASD Female, n = 12; NT Female, n = 14; ASD Male, n = 30; NT Male = 22), were similar according to age, IQ, and education. The results of the study indicated that the ASD Group as a whole performed worse on executive functioning tasks (Wisconsin Card Sorting Test, Trails Making Test) and memory-related tasks (Rey Auditory Verbal Learning Test, Weschler Memory Scale: Visual Reproduction) compared to the NT Group. Interactions of sex by diagnosis approached significance only within the WCST non-perseverative errors, with the women with ASD performing worse than NT women, but no group differences between men. Effect sizes between the female groups (ASD female vs. NT female) showed more than double that of the male groups (ASD male vs. NT male) for all WCST and AVLT measures. Participants with ASD had significantly smaller right hippocampal volumes than NT participants. In addition, all older women showed larger hippocampal volumes when corrected for total intracranial volume (TIV) compared to all older men. Overall, NT Females had significant correlations across all neuropsychological tests and their hippocampal volumes whereas no other group had significant correlations. These results suggest a tighter coupling between hippocampal size and cognition in NT Females than NT Males and both sexes with ASD. This study promotes further understanding of the neuropsychological differences between older men and women, both with and without ASD. Further research is needed on a larger sample of older women with and without ASD.
ContributorsWebb, Christen Len (Author) / Braden, B. Blair (Thesis advisor) / Azuma, Tamiko (Committee member) / Dixon, Maria (Committee member) / Arizona State University (Publisher)
Created2019
Description
This pilot study evaluated whether Story Champs and Puente de Cuentos helped bilingual preschoolers increase their usage of emotional terms and ability to tell stories. Participants in this study included 10 Spanish-English bilingual preschoolers. Intervention was conducted in 9 sessions over 3 days using the Test of Narrative Retell to measure results. Results did not find significant gains in either emotional term usage or ability to tell stories, but the results were promising as a pilot study.
ContributorsSato, Leslie Mariko (Author) / Restrepo, Maria (Thesis director) / Dixon, Maria (Committee member) / Department of Speech and Hearing Science (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
The Development of the Strengthening Skills Program for Autistic Adults: Feasibility & Acceptability
Description
The study focuses on the creation of the Strengthening Skills Program (SSP) and its feasibility and acceptability among autistic adults across the lifespan. Over the course of two years, the program has been developed and delivered to autistic adults with the aim of improving quality of life. The program included adapted social skills training from the UCLA Program for the Education and Enrichment of Relational Skills (PEERS) for young adults, adapted mindfulness training from Mindfulness-Based Stress Reduction, and custom executive skills training. Pre- and post-intervention acceptability questionnaires were gathered from 42 participants. Participants were separated into three groups (SSP, PEERS, and Delayed Treatment Control [DTC]; n=14 per group) stratified by age, gender, and if the participant had a program partner who would attend the program alongside as support. All groups were administered over Zoom once per week and lasted for 16 weeks each. The SSP group met for three hours each week and the PEERS group met for an hour and a half. Qualitative analysis was implemented on participant feedback to identify thematic codes related to their experiences with the programs. Overall, results suggest the SSP intervention had significantly higher acceptability ratings compared to PEERS alone and could be a useful addition to the limited interventions available for autistic adults.
ContributorsHill, Ethan Reed (Author) / Braden, Blair (Thesis advisor) / Matthews, Nicole (Committee member) / Dixon, Maria (Committee member) / Arizona State University (Publisher)
Created2023
Description
The present study aimed to compare brain activity changes related to proactive and reactive control strategies in patients with Parkinson’s disease during “On” levodopa and “Off” levodopa conditions. The study consisted of two participants who had received a prior diagnosis of Parkinson’s Disease. The participants completed AX-CPT task as a measure of attention control in two sessions: a) “On Levodopa” and b) “Off Levodopa” while they were in the fMRI scanner. Prior to the analysis, the T1- weighted anatomical scan images and the BOLD multiband functional images of both the participants were BIDS (Brain Imaging Data Structure) validated and preprocessed using the standard FMRIPrep pipeline. The imaging data was then analyzed using SPM12 (Statistical parametric mapping) software. Individual-level analysis of the imaging data was conducted by creating General Linear models for both the participants on “ON” and “OFF” levodopa conditions. The BOLD responses were compared using AY>BY and BX > BY contrasts. Where BX >, BY contrast, measured BOLD activity related to reactive control strategy and AY> BY contrast measured BOLD activity related to the proactive control strategy. It was observed that participants tended towards reactive control strategy in both “On” and “Off” levodopa conditions.
ContributorsDatta, Kalyani (Author) / Brewer, Gene (Thesis advisor) / Braden, B. Blair (Committee member) / Peterson, Daniel (Committee member) / Arizona State University (Publisher)
Created2022
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
Adults with autism spectrum disorder (ASD) face heightened risk of co-occurring psychiatric conditions, especially depression and anxiety disorders, which contribute to seven-fold higher suicide rates than the general population. Mindfulness-based stress reduction (MBSR) is an 8-week meditation intervention centered around training continuous redirection of attention toward present moment experience, and has been shown to improve mental health in autistic adults. However, the underlying therapeutic neural mechanisms and whether behavioral and brain changes are mindfulness-specific have yet to be elucidated. In this randomized clinical trial, I utilized functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) to characterize fMRI functional activity (Study 1) and connectivity (Study 2) and EEG neurophysiological (Study 3) changes between MBSR and a social support/relaxation education (SE) active control group. Study 1 revealed an MBSR-specific increase in the midcingulate cortex fMRI blood oxygen level dependent signal which was associated with reduced depression. Study 2 identified nonspecific intervention improvements in depression, anxiety, and autistic, and MBSR-specific improvements in the mindfulness trait ‘nonjudgment toward experience’ and in the executive functioning domain of working memory. MBSR-specific decreases in insula-thalamus and frontal pole-posterior cingulate functional connectivity was associated with improvements in anxiety, mindfulness traits, and working memory abilities. Both MBSR and SE groups showed decreased amygdala-sensorimotor and frontal pole-insula connectivity which correlated with reduced depression. Study 3 consisted of an EEG spectral power analysis at high-frequency brainwaves associated with default mode network (DMN) activity. Results showed MBSR-specific and nonspecific decreases in beta- and gamma-band power, with effects being generally more robust in the MBSR group; additionally, MBSR-specific decreases in posterior gamma correlated with anxiolytic effects. Collectively, these studies suggest: 1) social support is sufficient for improvements in depression, anxiety, and autistic traits; 2) MBSR provides additional benefits related to mindfulness traits and working memory; and 3) distinct and shared neural mechanisms of mindfulness training in adults with ASD, implicating the salience and default mode networks and high-frequency neurophysiology. Findings bear relevance to the development of personalized medicine approaches for psychiatric co-morbidity in ASD, provide putative targets for neurostimulation research, and warrant replication and extension using advanced multimodal imaging approaches.
ContributorsPagni, Broc (Author) / Braden, B. Blair (Thesis advisor) / Newbern, Jason (Thesis advisor) / Davis, Mary (Committee member) / Brewer, Gene (Committee member) / Arizona State University (Publisher)
Created2022
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