New Approaches to Characterizing Brain-Based Sex Differences in Autism: Insights into the Autism Sex Bias

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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

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.
Date Created
2022
Agent

Response Accuracy and Response Time in Multisensory Localization

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Description
Spatial awareness (i.e., the sense of the space that we are in) involves the integration of auditory, visual, vestibular, and proprioceptive sensory information of environmental events. Hearing impairment has negative effects on spatial awareness and can result in deficits in

Spatial awareness (i.e., the sense of the space that we are in) involves the integration of auditory, visual, vestibular, and proprioceptive sensory information of environmental events. Hearing impairment has negative effects on spatial awareness and can result in deficits in communication and the overall aesthetic experience of life, especially in noisy or reverberant environments. This deficit occurs as hearing impairment reduces the signal strength needed for auditory spatial processing and changes how auditory information is combined with other sensory inputs (e.g., vision). The influence of multisensory processing on spatial awareness in listeners with normal, and impaired hearing is not assessed in clinical evaluations, and patients’ everyday sensory experiences are currently not directly measurable. This dissertation investigated the role of vision in auditory localization in listeners with normal, and impaired hearing in a naturalistic stimulus setting, using natural gaze orienting responses. Experiments examined two behavioral outcomes—response accuracy and response time—based on eye movement in response to simultaneously presented auditory and visual stimuli. The first set of experiments examined the effects of stimulus spatial saliency on response accuracy and response time and the extent of visual dominance in both metrics in auditory localization. The results indicate that vision can significantly influence both the speed and accuracy of auditory localization, especially when auditory stimuli are more ambiguous. The influence of vision is shown for both normal hearing- and hearing-impaired listeners. The second set of experiments examined the effect of frontal visual stimulation on localizing an auditory target presented from in front of or behind a listener. The results show domain-specific effects of visual capture on both response time and response accuracy. These results support previous findings that auditory-visual interactions are not limited by the spatial rule of proximity. These results further suggest the strong influence of vision on both the processing and the decision-making stages of sound source localization for both listeners with normal, and impaired hearing.
Date Created
2021
Agent

Complimenting the Setting:
How Video Game Soundtrack Music Evokes its Environment

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Description
Instrumental music has been used to evoke natural environments and their qualities for centuries, and composers have employed a variety of methods in order to successfully invoke such sensations in their listeners. When composers and sound teams for video game

Instrumental music has been used to evoke natural environments and their qualities for centuries, and composers have employed a variety of methods in order to successfully invoke such sensations in their listeners. When composers and sound teams for video game soundtracks write pieces to accompany in-game settings, they may use a similar set of strategies. The nature of these tracks as an accompaniment to an interactive visual media and as a piece that must be able to indefinitely loop leads them to emphasize environment over emotion, and thus draws out or exaggerates these same techniques. This study seeks to understand the relationships between the acoustics of various setting backing tracks and the perceptual qualities of environments that listeners feel they evoke through the statistical method of multidimensional scaling. The relationships of three perceptual factors (coldness, brightness, wetness) and two acoustic factors (beats-per-minute, spectral envelope slope) are of greatest interest in this study.
Date Created
2022-05
Agent

El Papalote Perdido: A Codeswitching Children's Book and Shared Reading Guide to Promote Vocabulary

Description

The purpose of this creative project was to design a children’s book for parents, educators, caregivers, and speech language pathologists to promote vocabulary growth in young readers. Children’s books are commonly used in classrooms to connect students with new places

The purpose of this creative project was to design a children’s book for parents, educators, caregivers, and speech language pathologists to promote vocabulary growth in young readers. Children’s books are commonly used in classrooms to connect students with new places and ideas. Books are a powerful learning tool that speech-language pathologists utilize during therapy sessions to support their language and speech development. El Papalote Perdido (The Lost Kite) is a multidimensional children’s book that provides a representation of Hispanic culture, the biodiversity of the Sonoran Desert, and a shared book reading guide that can be a tool in classrooms and therapy sessions. This literature review summarizes the research and importance of Codeswitching, Shared Book Reading, and representation. The goal of the projected children’s book, El Papalote Perdido, is for Hispanic children to increase self-worth by being represented in the illustrations and Spanish embedded in the text. Additionally, the book is for adults to learn reading strategies to build young readers' language and literacy development.

Date Created
2022-05
Agent

Binaural Beats and Their Interaction Within the Superior Olivary Complex

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Description
This study focuses on the properties of binaural beats (BBs) compared to Monaural beats (MBs) and their steady-state response at the level of the Superior Olivary Complex (SOC). An auditory nerve stimulator was used to simulate the response of the

This study focuses on the properties of binaural beats (BBs) compared to Monaural beats (MBs) and their steady-state response at the level of the Superior Olivary Complex (SOC). An auditory nerve stimulator was used to simulate the response of the SOC. The simulator was fed either BBs or MBs stimuli to compare the SOC response. This was done for different frequencies at twenty, forty, and sixty hertz for comparison of the SOC response envelopes. A correlation between the SOC response envelopes for both types of beats and the waveform resulting from adding two tones together was completed. The highest correlation for BBs was found to be forty hertz and for MBs it was sixty hertz. A Fast Fourier Transform (FFT) was also completed on the stimulus envelope and the SOC response envelopes. The FFT was able to show that within the BBs presentation the envelopes of the original stimuli showed no difference frequency. However, the difference frequency was present in the binaural SOC response envelope. For the MBs, the difference frequency was present within the stimulus and the monaural SOC response envelope.
Date Created
2021
Agent

The effect of corpus callosum agenesis on the communication between cerebral hemispheres

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Description

Agenesis of the corpus callosum is the lack of the development of the corpus callosum. This condition can lead to impairments in language processing, epilepsy, and emotion and social functioning, but many individuals with this condition do not show any

Agenesis of the corpus callosum is the lack of the development of the corpus callosum. This condition can lead to impairments in language processing, epilepsy, and emotion and social functioning, but many individuals with this condition do not show any of these impairments. The present study investigated the connectivity of language and sensorimotor networks within an individual with agenesis of the corpus callosum using resting-state fMRI. The individual’s results were compared to those of neurotypical control subjects. It was hypothesized that the overall interhemispheric functional connectivity would be less than that of a control group in bilateral language networks, but the intrahemispheric connectivity, particularly within the sensorimotor network, would show greater functional connectivity. The results revealed significantly weaker functional connectivity in the individual with agenesis of the corpus callosum within the right ventral stream compared to the control group. There were no other significant inter or intrahemispheric differences in the functional connectivity of the language and sensorimotor networks. These findings lead us to conclude that the right hemisphere’s ventral stream perhaps relies upon connections with the left hemisphere’s language networks to maintain its typical functionality. The results of this study support the idea that, in the case of corpus callosum agenesis, the right language network may contribute differently to language processes than in neurotypical controls.

Date Created
2021-05
Agent

Corrective Responses to Auditory Feedback Perturbations During Speaking

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Description

The brain continuously monitors speech output to detect potential errors between its sensory prediction and its sensory production (Daliri et al., 2020). When the brain encounters an error, it generates a corrective motor response, usually in the opposite direction, to

The brain continuously monitors speech output to detect potential errors between its sensory prediction and its sensory production (Daliri et al., 2020). When the brain encounters an error, it generates a corrective motor response, usually in the opposite direction, to reduce the effect of the error. Previous studies have shown that the type of auditory error received may impact a participant’s corrective response. In this study, we examined whether participants respond differently to categorical or non-categorical errors. We applied two types of perturbation in real-time by shifting the first formant (F1) and second formant (F2) at three different magnitudes. The vowel /ɛ/ was shifted toward the vowel /æ/ in the categorical perturbation condition. In the non-categorical perturbation condition, the vowel /ɛ/ was shifted to a sound outside of the vowel quadrilateral (increasing both F1 and F2). Our results showed that participants responded to the categorical perturbation while they did not respond to the non-categorical perturbation. Additionally, we found that in the categorical perturbation condition, as the magnitude of the perturbation increased, the magnitude of the response increased. Overall, our results suggest that the brain may respond differently to categorical and non-categorical errors, and the brain is highly attuned to errors in speech.

Date Created
2021-05
Agent

Cognitive-communication Abilities in Bilinguals with a History of Mild Traumatic Brain Injury

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Description
Mild TBI (mTBI) has been associated with subtle executive function (EF) and

cognitive-communication deficits. In bilinguals, there are unique cognitive demands required to control and process two languages effectively. Surprisingly, little is known about the impact of mTBI on EF, communication,

Mild TBI (mTBI) has been associated with subtle executive function (EF) and

cognitive-communication deficits. In bilinguals, there are unique cognitive demands required to control and process two languages effectively. Surprisingly, little is known about the impact of mTBI on EF, communication, and language control in bilinguals. Therefore, the aim of this study was to examine the cognitive-communication abilities in bilinguals with a history of mTBI, identify any language control impairments, and explore the relationship between these language control impairments and domain-general cognitive control abilities. To this end, three-hundred and twenty-seven monolingual and bilingual college students with and without mTBI history participated in two experiments. In these experiments, EF, communication, and language control were examined using experimental and clinical tasks as well as self-rating scales. In Experiment 1, there was an interaction between mTBI history and language group (monolinguals vs. bilinguals) in how participants performed on a clinical measure of EF and a verbal fluency task. That is, only bilinguals with mTBI scored significantly lower on these tasks. In addition, there was a significant correlation between errors on a language switching task and performance on non-verbal EF tasks. In Experiment 2, a subgroup of bilinguals with persistent cognitive and behavioral symptoms reported greater everyday communication challenges in their first and second languages. Also, unbalanced bilinguals reported greater EF difficulties than monolinguals and balanced bilinguals regardless of mTBI history. In conclusion, bilinguals may face unique cognitive-communication challenges after mTBI. Factors related to the bilingual experience (e.g., language balance, daily language use) should be

considered in clinical evaluation and future research.
Date Created
2020
Agent

Towards Building an Intelligent Tutor for Gestural Languages using Concept Level Explainable AI

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Description
Languages, specially gestural and sign languages, are best learned in immersive environments with rich feedback. Computer-Aided Language Learning (CALL) solu- tions for spoken languages have successfully incorporated some feedback mechanisms, but no such solution exists for signed languages. Computer Aided

Languages, specially gestural and sign languages, are best learned in immersive environments with rich feedback. Computer-Aided Language Learning (CALL) solu- tions for spoken languages have successfully incorporated some feedback mechanisms, but no such solution exists for signed languages. Computer Aided Sign Language Learning (CASLL) is a recent and promising field of research which is made feasible by advances in Computer Vision and Sign Language Recognition(SLR). Leveraging existing SLR systems for feedback based learning is not feasible because their decision processes are not human interpretable and do not facilitate conceptual feedback to learners. Thus, fundamental research is needed towards designing systems that are modular and explainable. The explanations from these systems can then be used to produce feedback to aid in the learning process.

In this work, I present novel approaches for the recognition of location, movement and handshape that are components of American Sign Language (ASL) using both wrist-worn sensors as well as webcams. Finally, I present Learn2Sign(L2S), a chat- bot based AI tutor that can provide fine-grained conceptual feedback to learners of ASL using the modular recognition approaches. L2S is designed to provide feedback directly relating to the fundamental concepts of ASL using an explainable AI. I present the system performance results in terms of Precision, Recall and F-1 scores as well as validation results towards the learning outcomes of users. Both retention and execution tests for 26 participants for 14 different ASL words learned using learn2sign is presented. Finally, I also present the results of a post-usage usability survey for all the participants. In this work, I found that learners who received live feedback on their executions improved their execution as well as retention performances. The average increase in execution performance was 28% points and that for retention was 4% points.
Date Created
2020
Agent

Relations Between Central Executive Function and Scores on an ADHD Rating Scale in Second Grade Children

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Description
Purpose: Children with attention-deficit/hyperactivity disorder (ADHD) have been found to have central executive deficits in working memory as well as less academic success than children with typical development. The purpose of this study was to determine which components of central

Purpose: Children with attention-deficit/hyperactivity disorder (ADHD) have been found to have central executive deficits in working memory as well as less academic success than children with typical development. The purpose of this study was to determine which components of central executive function were most closely related to parental rating scores of attention.
Method: Two hundred twenty three 2nd graders with typical development, dyslexia, developmental language disorder (DLD), or dyslexia/DLD completed three central executive tasks from the Comprehensive Assessment Battery for Children–Working Memory (Gray, Alt, Hogan, Green, & Cowan, n.d.). Parents of the children completed the ADHD Rating Scale-IV: Home Version for their child. None of the participants had been diagnosed with ADD/ADHD
Results: When diagnostic group performance was compared we found significant differences on each central executive task. When ADHD group performance was compared we found a significant between-group performance only on the n-back visual task with the high-risk group scoring lower than the other two groups. ADHD rating scores predicted a significant amount of variance for each central executive task, but percentages were small (3%-6%).
Discussion: Working memory is known to be related to attention control. Stronger attentional control is associated with a higher working memory performance. Our study showed that children most at risk for ADD/ADHD based on parent ratings scored lowest on the visuospatial task, likely because rehearsal of visuospatial information is not possible so relies more heavily on attention. This study is a step toward considering how attention affects working memory performance so that both can be considered when designing instruction and interventions.
Date Created
2019-12
Agent