Matching Items (8)
Filtering by
- All Subjects: Dyslexia
- All Subjects: Multitasking
- Creators: Peter, Beate
- Member of: Theses and Dissertations
Description
The purpose of this project was to investigate the hypothesis that adults with dyslexia tend to have lower accuracies in and take longer to process tasks involving the serial order of letters, compared to age and gender-matched controls. In Experiment 1, participants evaluated word pairs for differences. Half of the word pairs that they evaluated were the same, whereas the remaining word pairs differed along specific parameters such as sequential rearrangements ("left" vs "felt"), left/right reversals ("cob" vs "cod"), up/down reversals ("best" vs "pest"), homophones ("grown" vs "groan"), visual letter similarities ("tight" vs "fight"), and generic substitutions ("moan" vs "loan"). The response times and accuracies of both groups were recorded. In Experiment 2, the participants spelled single words to dictation using the spelling subtest from the Wechsler Individual Achievement Test\u2014II. Spelling errors were evaluated for errors such as sequential rearrangements, left/right reversals, homophones, substitutions, orthographic violations, omissions, and insertions. An example of a spelling error is the word "excitement" misspelled as "excietment", which involves a sequential rearrangement error. Another example is the word "apparently" misspelled as "aparently,", which involves an error of omission. Error frequencies within these error types for both groups were recorded. Experiment 3 evaluated whether left/right reversal errors during the letter-naming Rapid Automatized Naming and Rapid Alternating Stimulus (RAN/RAS) task were associated with left/right errors during word pair comparison and spelling and whether these visual reversal errors were also associated with errors of serial order. The group with dyslexia was split into two groups: group 1 included participants who did not make any left/right reversals during the RAN/RAS task and group 2 included participants who did make left/right reversals during the RAN/RAS task. The accuracies and reaction times of these three groups during the comparison and spelling assessments were recorded. The results of experiment 1 revealed that that adults with dyslexia had a significantly higher reaction time and lower accuracy during the sequential rearrangement and left/right reversal conditions. Experiment 2 demonstrated that the group with dyslexia made significantly more spelling errors during the homophone and omission conditions. The results of Experiment 3 showed associations between the sequential rearrangement and left/right conditions in both the word pair comparison and spelling task for participants with dyslexia who made left/right reversals during the RAN/RAS task. Overall, the participants with dyslexia who made left/right reversals during the RAN/RAS task seemed to have greater difficulty understanding the orientation of letters that occur on a horizontal plane, since this underlying pattern of errors was also seen throughout the spelling and word comparison tasks. These results show that left/right reversals and errors of serial order are evident in some, but not all adults with dyslexia. These errors may also characterize a distinct subtype of dyslexia. Further, errors of left/right reversal and serial order appear to be associated, so left/right reversals may represent a special form of serial order error that involves a change in the order of visual processing in the horizontal but not vertical axis of letter orientation.
ContributorsAlbert, Andria (Author) / Peter, Beate (Thesis director) / Gray, Shelley (Committee member) / School of International Letters and Cultures (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
Description
The International Dyslexia Association defines dyslexia as a learning disorder that is characterized by poor spelling, decoding, and word recognition abilities. There is still no known cause of dyslexia, although it is a very common disability that affects 1 in 10 people. Previous fMRI and MRI research in dyslexia has explored the neural correlations of hemispheric lateralization and phonemic awareness in dyslexia. The present study investigated the underlying neurobiology of five adults with dyslexia compared to age- and sex-matched control subjects using structural and functional magnetic resonance imaging. All subjects completed a large battery of behavioral tasks as part of a larger study and underwent functional and structural MRI acquisition. This data was collected and preprocessed at the University of Washington. Analyses focused on examining the neural correlates of hemispheric lateralization, letter reversal mistakes, reduced processing speed, and phonemic awareness. There were no significant findings of hemispheric differences between subjects with dyslexia and controls. The subject making the largest amount of letter reversal errors had deactivation in their cerebellum during the fMRI language task. Cerebellar white matter volume and surface area of the premotor cortex was the largest in the individual with the slowest reaction time to tapping. Phonemic decoding efficiency had a high correlation with neural activation in the primary motor cortex during the fMRI motor task (r=0.6). Findings from the present study suggest that brain regions utilized during motor control, such as the cerebellum, premotor cortex, and primary motor cortex, may have a larger role in dyslexia then previously considered. Future studies are needed to further distinguish the role of the cerebellum and other motor regions in relation to motor control and language processing deficits related to dyslexia.
ContributorsHoulihan, Chloe Carissa Prince (Author) / Rogalsky, Corianne (Thesis director) / Peter, Beate (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
With social technology on the rise, it is no surprise that young students are at the forefront of its use and impact, particularly in the realm of education. Due to greater accessibility to technology, media multitasking and task-switching are becoming increasingly prominent in learning environments. While technology can have numerous benefits, current literature, though somewhat limited in this scope, overwhelmingly shows it can also be detrimental for academic performance and learning when used improperly. While much of the existing literature regarding the impact of technology on multitasking and task-switching in learning environments is limited to self-report data, it presents important findings and potential applications for modernizing educational institutions in the wake of technological dependence. This literature review summarizes and analyzes the studies in this area to date in an effort to provide a better understanding of the impact of social technology on student learning. Future areas of research and potential strategies to adapt to rising technological dependency are also discussed, such as using a brief "technology break" between periods of study. As of yet, the majority of findings in this research area suggest the following: multitasking while studying lengthens the time required for completion; multitasking during lectures can affect memory encoding and comprehension; excessive multitasking and academic performance are negatively correlated; metacognitive strategies for studying have potential for reducing the harmful effects of multitasking; and the most likely reason students engage in media-multitasking at the cost of learning is the immediate emotional gratification. Further research is still needed to fill in gaps in literature, as well as develop other potential perspectives relevant to multitasking in academic environments.
ContributorsKhanna, Sanjana (Author) / Roberts, Nicole (Thesis director) / Burleson, Mary (Committee member) / Barrett, The Honors College (Contributor)
Created2016-12
Description
More than a century of research has investigated the etiology of dyslexia, coalescing around ‘phonological awareness’ – the ability to recognize and manipulate phonemes – as a trait typically deficient in reading disorders. Meanwhile, the last few decades of research in neuroscience have highlighted the brain as a predictive organ, which subliminally calibrates sensory expectations according to experience. Do the brains of adults with dyslexia respond differently than those of matched controls to expected tones and unexpected omissions? While auditory oddball paradigms have previously been used to study dyslexia, these studies often interpret group differences to indicate deficit auditory discrimination rather than deficit auditory prediction. The current study takes a step toward fusing theories of predictive coding and dyslexia, finding that event-related potentials related to auditory prediction are attenuated in adults with dyslexia compared with typical controls. It further suggests that understanding dyslexia, and perhaps other psychiatric disorders, in terms of contributory neural systems will elucidate shared and distinct etiologies.
ContributorsBennett, Augustin (Author) / Peter, Beate (Thesis advisor) / Daliri, Ayoub (Committee member) / Goldinger, Stephen (Committee member) / Arizona State University (Publisher)
Created2023
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
In the study of the human brain’s ability to multitask, there are two perspectives: concurrent multitasking (performing multiple tasks simultaneously) and sequential multitasking (switching between tasks). The goal of this study is to investigate the human brain’s ability to “multitask” with multiple demanding stimuli of approximately equal concentration, from an electrophysiological perspective different than that of stimuli which don’t require full attention or exhibit impulsive multitasking responses. This study investigates the P3 component which has been experimentally proven to be associated with mental workload through information processing and cognitive function in visual and auditory tasks, where in the multitasking domain the greater attention elicited, the larger P3 waves are produced. This experiment compares the amplitude of the P3 component of individual stimulus presentation to that of multitasking trials, taking note of the brain workload. This study questions if the average wave amplitude in a multitasking ERP experiment will be the same as the grand average when performing the two tasks individually with respect to the P3 component. The hypothesis is that the P3 amplitude will be smaller in the multitasking trial than in the individual stimulus presentation, indicating that the brain is not actually concentrating on both tasks at once (sequential multitasking instead of concurrent) and that the brain is not focusing on each stimulus to the same degree when it was presented individually. Twenty undergraduate students at Barrett, the Honors College at Arizona State University (10 males and 10 females, with a mean age of 18.75 years, SD= 1.517) right handed, with normal or corrected visual acuity, English as first language, and no evidence of neurological compromise participated in the study. The experiment results revealed that one- hundred percent of participants undergo sequential multitasking in the presence of two demanding stimuli in the electrophysiological data, behavioral data, and subjective data. In this particular study, these findings indicate that the presence of additional demanding stimuli causes the workload of the brain to decrease as attention deviates in a bottleneck process to the multiple requisitions for focus, indicated by a reduced P3 voltage amplitude with the multitasking stimuli when compared to the independent. This study illustrates the feasible replication of P3 cognitive workload results for demanding stimuli, not only impulsive-response experiments, to suggest the brain’s tendency to undergo sequential multitasking when faced with multiple demanding stimuli. In brief, this study demonstrates that when higher cognitive processing is required to interpret and respond to the stimuli, the human brain results to sequential multitasking (task- switching, not concurrent multitasking) in the face of more challenging problems with each stimulus requiring a higher level of focus, workload, and attention.
ContributorsNeill, Ryan (Author) / Brewer, Gene (Thesis director) / Peter, Beate (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Objective: A recent electroencephalogram (EEG) study of adults with dyslexia showed that individuals with dyslexia have diminished auditory sensory gating compared to typical controls. Previous studies done involving intoxication and its effect on sensory gating and creativity have shown that there is a positive correlation between creativity (divergent thinking problem solving) and sensory gating deficiency. With previous study findings, the link between dyslexia and sensory gating deficiency and the link between sensory gating deficiency and creativity have been shown, but not the link between dyslexia and creativity. This pilot study aims to address this knowledge gap using event-related potentials.
Methods: Two adults with dyslexia and 4 control adults participated in an auditory gating test using tone pairs. Latencies and Amplitudes for the N100 and P200 responses were recorded and analyzed. Participants were also administered the Abbreviated Torrance Test for Adults (ATTA), a test of creative ability designed to evaluate divergent thinking in individuals. Results were averaged and compared.
Results: The averaged difference in measured N100 amplitudes between tone 1 and tone 2 was significantly larger in the control group compared to the difference observed in the dyslexia group. In particular, one participant with dyslexia who had low scores on a task of rapid word recognition also showed no evidence of gating at the N100 component, whereas the other participant with dyslexia with good word recognition scores showed evidence of intact gating. The averaged difference in measured P200 amplitude between tone 1 and tone 2 was larger in the dyslexia group compared to the control group; however, the difference was small enough to be considered insignificant. The total average ATTA score for the control group was higher than the average of the dyslexia group. This difference in total average was less than one point on a 106-point scale.
Conclusions: Neural sensory gating occurs approximately 100 ms after the onset of a stimulus and is diminished in adults with dyslexia who also have deficits in rapid word recognition. There is a difference in creativity, in terms of divergent thinking, between those with dyslexia and those without (controls scored higher on average); however, the difference is not significant (less than one point). Dyslexia scores were more consistent than controls.
Methods: Two adults with dyslexia and 4 control adults participated in an auditory gating test using tone pairs. Latencies and Amplitudes for the N100 and P200 responses were recorded and analyzed. Participants were also administered the Abbreviated Torrance Test for Adults (ATTA), a test of creative ability designed to evaluate divergent thinking in individuals. Results were averaged and compared.
Results: The averaged difference in measured N100 amplitudes between tone 1 and tone 2 was significantly larger in the control group compared to the difference observed in the dyslexia group. In particular, one participant with dyslexia who had low scores on a task of rapid word recognition also showed no evidence of gating at the N100 component, whereas the other participant with dyslexia with good word recognition scores showed evidence of intact gating. The averaged difference in measured P200 amplitude between tone 1 and tone 2 was larger in the dyslexia group compared to the control group; however, the difference was small enough to be considered insignificant. The total average ATTA score for the control group was higher than the average of the dyslexia group. This difference in total average was less than one point on a 106-point scale.
Conclusions: Neural sensory gating occurs approximately 100 ms after the onset of a stimulus and is diminished in adults with dyslexia who also have deficits in rapid word recognition. There is a difference in creativity, in terms of divergent thinking, between those with dyslexia and those without (controls scored higher on average); however, the difference is not significant (less than one point). Dyslexia scores were more consistent than controls.
ContributorsDuran, Isaac (Author) / Peter, Beate (Thesis director) / Daliri, Ayoub (Committee member) / Rogalsky, Corianne (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Dyslexia is a learning disability that negatively affects reading, writing, and spelling development at the word level in 5%-9% of children. The phenotype is variable and complex, involving several potential cognitive and physical concomitants such as sensory dysregulation and immunodeficiencies. The biological pathogenesis is not well-understood. Toward a better understanding of the biological drivers of dyslexia, we conducted the first joint exome and metabolome investigation in a pilot sample of 30 participants with dyslexia and 13 controls. In the metabolite analysis, eight metabolites of interest emerged (pyridoxine, kynurenic acid, citraconic acid, phosphocreatine, hippuric acid, xylitol, 2-deoxyuridine, and acetylcysteine). A metabolite-metabolite interaction analysis identified Krebs cycle intermediates that may be implicated in the development of dyslexia. Gene ontology analysis based on exome variants resulted in several pathways of interest, including the sensory perception of smell (olfactory) and immune system-related responses. In the joint exome and metabolite analysis, the olfactory transduction pathway emerged as the primary pathway of interest. Although the olfactory transduction and Krebs cycle pathways have not previously been described in the dyslexia literature, these pathways have been implicated in other neurodevelopmental disorders including autism spectrum disorder and obsessive-compulsive disorder, suggesting the possibility of these pathways playing a role in dyslexia as well. Immune system response pathways, on the other hand, have been implicated in both dyslexia and other neurodevelopmental disorders.
ContributorsNandakumar, Rohit (Author) / Dinu, Valentin (Thesis director) / Peter, Beate (Committee member) / Barrett, The Honors College (Contributor) / College of Health Solutions (Contributor)
Created2022-05