Matching Items (26)
Filtering by
- All Subjects: Neurosciences
- All Subjects: Speech therapy
- All Subjects: Executive Function
- Creators: Gray, Shelley
- Creators: Greger, Bradley
- Resource Type: Text
Description
The current study employs item difficulty modeling procedures to evaluate the feasibility of potential generative item features for nonword repetition. Specifically, the extent to which the manipulated item features affect the theoretical mechanisms that underlie nonword repetition accuracy was estimated. Generative item features were based on the phonological loop component of Baddelely's model of working memory which addresses phonological short-term memory (Baddeley, 2000, 2003; Baddeley & Hitch, 1974). Using researcher developed software, nonwords were generated to adhere to the phonological constraints of Spanish. Thirty-six nonwords were chosen based on the set item features identified by the proposed cognitive processing model. Using a planned missing data design, two-hundred fifteen Spanish-English bilingual children were administered 24 of the 36 generated nonwords. Multiple regression and explanatory item response modeling techniques (e.g., linear logistic test model, LLTM; Fischer, 1973) were used to estimate the impact of item features on item difficulty. The final LLTM included three item radicals and two item incidentals. Results indicated that the LLTM predicted item difficulties were highly correlated with the Rasch item difficulties (r = .89) and accounted for a substantial amount of the variance in item difficulty (R2 = .79). The findings are discussed in terms of validity evidence in support of using the phonological loop component of Baddeley's model (2000) as a cognitive processing model for nonword repetition items and the feasibility of using the proposed radical structure as an item blueprint for the future generation of nonword repetition items.
ContributorsMorgan, Gareth Philip (Author) / Gorin, Joanna (Thesis advisor) / Levy, Roy (Committee member) / Gray, Shelley (Committee member) / Arizona State University (Publisher)
Created2011
Description
Frequency effects favoring high print-frequency words have been observed in frequency judgment memory tasks. Healthy young adults performed frequency judgment tasks; one group performed a single task while another group did the same task while alternating their attention to a secondary task (mathematical equations). Performance was assessed by correct and error responses, reaction times, and accuracy. Accuracy and reaction times were analyzed in terms of memory load (task condition), number of repetitions, effect of high vs. low print-frequency, and correlations with working memory span. Multinomial tree analyses were also completed to investigate source vs. item memory and revealed a mirror effect in episodic memory experiments (source memory), but a frequency advantage in span tasks (item memory). Interestingly enough, we did not observe an advantage for high working memory span individuals in frequency judgments, even when participants split their attention during the dual task (similar to a complex span task). However, we concluded that both the amount of attentional resources allocated and prior experience with an item affect how it is stored in memory.
ContributorsPeterson, Megan Paige (Author) / Azuma, Tamiko (Thesis advisor) / Gray, Shelley (Committee member) / Liss, Julie (Committee member) / Arizona State University (Publisher)
Created2013
Description
Identification of primary language impairment (PLI) in sequential bilingual children is challenging because of the interaction between PLI and second language (L2) proficiency. An important step in improving the accurate diagnosis of PLI in bilingual children is to investigate how differences in L2 performance are affected by a length of L2 exposure and how L2 assessment contributes to differentiation between children with and without PLI at different L2 proficiency levels. Sixty one children with typical language development (TD) ages 5;3-8 years and 12 children with PLI ages 5;5-7;8 years participated. Results revealed that bilingual children with and without PLI, who had between 1 and 3 years of L2 exposure, did not differ in mean length of utterance (MLU), number of different words, percent of maze words, and performance on expressive and receptive grammatical tasks in L2. Performance on a grammaticality judgment task by children with and without PLI demonstrated the largest effect size, indicating that it may potentially contribute to identification of PLI in bilingual populations. In addition, children with PLI did not demonstrate any association between the length of exposure and L2 proficiency, suggesting that they do not develop their L2 proficiency in relation to length of exposure in the same manner as children with TD. Results also indicated that comprehension of grammatical structures and expressive grammatical task in L2 may contribute to differentiation between the language ability groups at the low and intermediate-high proficiency levels. The discriminant analysis with the entire sample of bilingual children with and without PLI revealed that among L2 measures, only MLU contributed to the discrimination between the language ability groups. However, poor classification accuracy suggested that MLU alone is not a sufficient predictor of PLI. There were significant differences among L2 proficiency levels in children with TD in MLU, number of different words, and performance on the expressive and receptive grammatical tasks in L2, indicating that L2 proficiency level may potentially impact the differentiation between language difficulties due to typical L2 acquisition processes and PLI.
ContributorsSmyk, Ekaterina (Author) / Restrepo, Maria Adelaida (Thesis advisor) / Gorin, Joanna (Committee member) / Gray, Shelley (Committee member) / Arizona State University (Publisher)
Created2012
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
Description
Multisensory integration is the process by which information from different sensory modalities is integrated by the nervous system. This process is important not only from a basic science perspective but also for translational reasons, e.g., for the development of closed-loop neural prosthetic systems. A mixed virtual reality platform was developed to study the neural mechanisms of multisensory integration for the upper limb during motor planning. The platform allows for selection of different arms and manipulation of the locations of physical and virtual target cues in the environment. The system was tested with two non-human primates (NHP) trained to reach to multiple virtual targets. Arm kinematic data as well as neural spiking data from primary motor (M1) and dorsal premotor cortex (PMd) were collected. The task involved manipulating visual information about initial arm position by rendering the virtual avatar arm in either its actual position (veridical (V) condition) or in a different shifted (e.g., small vs large shifts) position (perturbed (P) condition) prior to movement. Tactile feedback was modulated in blocks by placing or removing the physical start cue on the table (tactile (T), and no-tactile (NT) conditions, respectively). Behaviorally, errors in initial movement direction were larger when the physical start cue was absent. Slightly larger directional errors were found in the P condition compared to the V condition for some movement directions. Both effects were consistent with the idea that erroneous or reduced information about initial hand location led to movement direction-dependent reach planning errors. Neural correlates of these behavioral effects were probed using population decoding techniques. For small shifts in the visual position of the arm, no differences in decoding accuracy between the T and NT conditions were observed in either M1 or PMd. However, for larger visual shifts, decoding accuracy decreased in the NT condition, but only in PMd. Thus, activity in PMd, but not M1, may reflect the uncertainty in reach planning that results when sensory cues regarding initial hand position are erroneous or absent.
ContributorsPhataraphruk, Preyaporn Kris (Author) / Buneo, Christopher A (Thesis advisor) / Zhou, Yi (Committee member) / Helms Tillery, Steve (Committee member) / Greger, Bradley (Committee member) / Santello, Marco (Committee member) / Arizona State University (Publisher)
Created2023
Description
Safety and efficacy of neuromodulation are influenced by abiotic factors like failure of implants, biotic factors like tissue damage, and molecular and cellular mechanisms of neuromodulation. Accelerated lifetime test (ALT) predict lifetime of implants by accelerating failure modes in controlled bench-top conditions. Current ALT models do not capture failure modes involving biological mechanisms. First part of this dissertation is focused on developing ALTs for predicting failure of chronically implanted tungsten stimulation electrodes. Three factors used in ALT are temperature, H2O2 concentration, and amount of charge delivered through electrode to develop a predictive model of lifetime for stimulation electrodes. Second part of this dissertation is focused on developing a novel method for evaluating tissue response to implants and electrical stimulation. Current methods to evaluate tissue damage in the brain require invasive and terminal procedures that have poor clinical translation. I report a novel non-invasive method that sampled peripheral blood monocytes (PBMCs) and used enzyme-linked immunoassay (ELISA) to assess level of glial fibrillary acidic protein (GFAP) expression and fluorescence-activated cell sorting (FACS) to quantify number of GFAP expressing PBMCs. Using this method, I was able to detect and quantify GFAP expression in PBMCs. However, there was no statistically significant difference in GFAP expression between stimulatory and non-stimulatory implants. Final part of this dissertation assessed molecular and cellular mechanisms of non-invasive ultrasound neuromodulation approach. Unlike electrical stimulation, cellular mechanisms of ultrasound-based neuromodulation are not fully known. Final part of this dissertation assessed role of mechanosensitive ion channels and neuronal nitric oxide production in cell cultures under ultrasound excitation. I used fluorescent imaging to quantify expression of nitric oxide in neuronal cell cultures in response to ultrasound stimulation. Results from these experiments indicate that neuronal nitric oxide production increased in response to ultrasound stimulation compared to control and decreased when mechanosensitive ion channels were suppressed. Two novel methods developed in this dissertation enable assessment of lifetime and safety of neuromodulation techniques that use electrical stimulation through implants. The final part of this dissertation concludes that non-invasive ultrasound neuromodulation may be mediated through neuronal nitric oxide even in absence of activation of mechanosensitive ion channels.
ContributorsVoziyanov, Vladislav (Author) / Muthuswamy, Jitendran (Thesis advisor) / Smith, Barbara (Committee member) / Greger, Bradley (Committee member) / Abbas, James (Committee member) / Okandan, Murat (Committee member) / Arizona State University (Publisher)
Created2022
Description
Information processing in the brain is mediated by network interactions between anatomically distant (centimeters apart) regions of cortex and network action is fundamental to human behavior. Disruptive activity of these networks may allow a variety of diseases to develop. Degradation or loss of network function in the brain can affect many aspects of the human experience; motor disorder, language difficulties, memory loss, mood swings, and more. The cortico-basal ganglia loop is a system of networks in the brain between the cortex, basal ganglia, the thalamus, and back to the cortex. It is not one singular circuit, but rather a series of parallel circuits that are relevant towards motor output, motor planning, and motivation and reward. Studying the relationship between basal ganglia neurons and cortical local field potentials may lead to insights about neurodegenerative diseases and how these diseases change the cortico-basal ganglia circuit. Speech and language are uniquely human and require the coactivation of several brain regions. The various aspects of language are spread over the temporal lobe and parts of the occipital, parietal, and frontal lobe. However, the core network for speech production involves collaboration between phonologic retrieval (encoding ideas into syllabic representations) from Wernicke’s area, and phonemic encoding (translating syllables into motor articulations) from Broca’s area. Studying the coactivation of these brain regions during a repetitive speech production task may lead to a greater understanding of their electrophysiological functional connectivity. The primary purpose of the work presented in this document is to validate the use of subdural microelectrodes in electrophysiological functional connectivity research as these devices best match the spatial and temporal scales of brain activity. Neuron populations in the cortex are organized into functional units called cortical columns. These cortical columns operate on the sub-millisecond temporal and millimeter spatial scale. The study of brain networks, both in healthy and unwell individuals, may reveal new methodologies of treatment or management for disease and injury, as well as contribute to our scientific understanding of how the brain works.
ContributorsO'Neill, Kevin John (Author) / Greger, Bradley (Thesis advisor) / Santello, Marco (Committee member) / Helms Tillery, Stephen (Committee member) / Papandreou-Suppapola, Antonia (Committee member) / Kleim, Jeffery (Committee member) / Arizona State University (Publisher)
Created2021
Description
The purpose of this study was to evaluate the effects of parent training in the Enhanced Milieu Teaching with Phonological Emphasis (EMT+PE) intervention program, using telepractice, on parent strategy use and child speech and language outcomes for children with repaired cleft palate with or without lip (CP/L). Four parent child dyads participated in the study. Child participants ranged in age from 28 to 53 months at the beginning of intervention and all had a diagnosis of nonsyndromic CP/L. Participants received two-to-three parent training sessions and twice weekly telepractice intervention sessions. Parents increased their use of EMT+PE strategies throughout intervention with the Modeling and Expansion and Prompting and Recasting strategies resulting in significant intervention effects. Moreover, parents maintained increased strategy use following the conclusion of direct intervention. A positive improvement in child speech and language outcomes was seen across intervention. This study showed that telepractice is an effective service delivery model for parent training and subsequent intervention session in EMT+PE strategy use to support the speech and language development for children with CP/L.
ContributorsEllis, Paige Kathryn (Author) / Scherer, Nancy J (Thesis advisor) / Gray, Shelley (Committee member) / Peter, Beate (Committee member) / Lien, Kari (Committee member) / Arizona State University (Publisher)
Created2022
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
Currently, there are few quality tools available to screen for developmental language disorder (DLD) in Spanish-speaking children despite the continued increase of this population in the United States. The lack of valid and reliable screening tools may be a factor leading to difficulties with the identification of and delivery of services to these children. This study plans to improve upon the screening of Spanish-English bilingual children.The Spanish Screener for Language Impairment in Children (SSLIC) tests Spanish oral language skills in Spanish-speaking children. It measures language skills through morphology elicitation of Spanish clitics, prepositions, derivational morphemes, subjunctive verb tenses, and articles and repetition of nonwords and sentences, which have all been shown to be affected in Spanish-speaking children with DLD.
The purpose of the study is to provide preliminary validity evidence of the SSLIC. Children's results on the SSLIC were compared to other validated measures. Fourteen Spanish-English bilingual students were recruited: 11 children with typical language development (TD) and 3 with DLD. The Bilingual English-Spanish Assessment and the Dynamic Measure of Oral Narrative Discourse were used to establish preliminary validity evidence. Pearson correlations were run to determine if SSLIC scores correlated with other validated measures. Significant correlations were found between the SSLIC’s scores and scores on the BESA. One-way analysis of variance (ANOVA) was used to determine mean differences between groups. No significant mean differences for SSLIC scores were found between children with typical and atypical language. Yet, effect sizes suggested group differences. Point to point analysis revealed that the SSLIC has excellent inter-rater reliability.
Despite a small sample size, this study serves as preliminary evidence that the SSLIC is both valid and reliable and supports that the SSLIC has the potential to be used as a screening tool for DLD for Spanish-speaking kindergarten and 1st grade students with further validation, which should continue.
ContributorsSmith, Brandon Earl (Author) / Restrepo, María A (Thesis advisor) / Gray, Shelley (Committee member) / Brown, Jean C (Committee member) / Moen, Theresa C (Committee member) / Arizona State University (Publisher)
Created2023