Matching Items (6)
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- All Subjects: working memory
- Creators: Azuma, Tamiko
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
Military veterans have a significantly higher incidence of mild traumatic brain injury (mTBI), depression, and Post-traumatic stress disorder (PTSD) compared to civilians. Military veterans also represent a rapidly growing subgroup of college students, due in part to the robust and financially incentivizing educational benefits under the Post-9/11 GI Bill. The overlapping cognitively impacting symptoms of service-related conditions combined with the underreporting of mTBI and psychiatric-related conditions, make accurate assessment of cognitive performance in military veterans challenging. Recent research findings provide conflicting information on cognitive performance patterns in military veterans. The purpose of this study was to determine whether service-related conditions and self-assessments predict performance on complex working memory and executive function tasks for military veteran college students. Sixty-one military veteran college students attending classes at Arizona State University campuses completed clinical neuropsychological tasks and experimental working memory and executive function tasks. The results revealed that a history of mTBI significantly predicted poorer performance in the areas of verbal working memory and decision-making. Depression significantly predicted poorer performance in executive function related to serial updating. In contrast, the commonly used clinical neuropsychological tasks were not sensitive service-related conditions including mTBI, PTSD, and depression. The differing performance patterns observed between the clinical tasks and the more complex experimental tasks support that researchers and clinicians should use tests that sufficiently tax verbal working memory and executive function when evaluating the subtle, higher-order cognitive deficits associated with mTBI and depression.
ContributorsGallagher, Karen Louise (Author) / Azuma, Tamiko (Thesis advisor) / Liss, Julie (Committee member) / Lavoie, Michael (Committee member) / Arizona State University (Publisher)
Created2017
The neurobiology of sentence comprehension: an fMRI study of late American Sign Language acquisition
Description
Language acquisition is a phenomenon we all experience, and though it is well studied many questions remain regarding the neural bases of language. Whether a hearing speaker or Deaf signer, spoken and signed language acquisition (with eventual proficiency) develop similarly and share common neural networks. While signed language and spoken language engage completely different sensory modalities (visual-manual versus the more common auditory-oromotor) both languages share grammatical structures and contain syntactic intricacies innate to all languages. Thus, studies of multi-modal bilingualism (e.g. a native English speaker learning American Sign Language) can lead to a better understanding of the neurobiology of second language acquisition, and of language more broadly. For example, can the well-developed visual-spatial processing networks in English speakers support grammatical processing in sign language, as it relies heavily on location and movement? The present study furthers the understanding of the neural correlates of second language acquisition by studying late L2 normal hearing learners of American Sign Language (ASL). Twenty English speaking ASU students enrolled in advanced American Sign Language coursework participated in our functional Magnetic Resonance Imaging (fMRI) study. The aim was to identify the brain networks engaged in syntactic processing of ASL sentences in late L2 ASL learners. While many studies have addressed the neurobiology of acquiring a second spoken language, no previous study to our knowledge has examined the brain networks supporting syntactic processing in bimodal bilinguals. We examined the brain networks engaged while perceiving ASL sentences compared to ASL word lists, as well as written English sentences and word lists. We hypothesized that our findings in late bimodal bilinguals would largely coincide with the unimodal bilingual literature, but with a few notable differences including additional attention networks being engaged by ASL processing. Our results suggest that there is a high degree of overlap in sentence processing networks for ASL and English. There also are important differences in regards to the recruitment of speech comprehension, visual-spatial and domain-general brain networks. Our findings suggest that well-known sentence comprehension and syntactic processing regions for spoken languages are flexible and modality-independent.
ContributorsMickelsen, Soren Brooks (Co-author) / Johnson, Lisa (Co-author) / Rogalsky, Corianne (Thesis director) / Azuma, Tamiko (Committee member) / Howard, Pamela (Committee member) / Department of Speech and Hearing Science (Contributor) / School of Human Evolution and Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
The RAS/MAPK (RAS/Mitogen Activated Protein Kinase) pathway is a highly conserved, canonical signaling cascade that is highly involved in cellular growth and proliferation as well as cell migration. As such, it plays an important role in development, specifically in development of the nervous system. Activation of ERK is indispensable for the differentiation of Embryonic Stem Cells (ESC) into neuronal precursors (Li z et al, 2006). ERK signaling has also shown to mediate Schwann cell myelination of the peripheral nervous system (PNS) as well as oligodendrocyte proliferation (Newbern et al, 2011). The class of developmental disorders that result in the dysregulation of RAS signaling are known as RASopathies. The molecular and cell-specific consequences of these various pathway mutations remain to be elucidated. While there is evidence for altered DNA transcription in RASopathies, there is little work examining the effects of the RASopathy-linked mutations on protein translation and post-translational modifications in vivo. RASopathies have phenotypic and molecular similarities to other disorders such as Fragile X Syndrome (FXS) and Tuberous Sclerosis (TSC) that show evidence of aberrant protein synthesis and affect related pathways. There are also well-defined downstream RAS pathway elements involved in translation. Additionally, aberrant corticospinal axon outgrowth has been observed in disease models of RASopathies (Xing et al, 2016). For these reasons, this present study examines a subset of proteins involved in translation and translational regulation in the context of RASopathy disease states. Results indicate that in both of the tested RASopathy model systems, there is altered mTOR expression. Additionally the loss of function model showed a decrease in rps6 activation. This data supports a role for the selective dysregulation of translational control elements in RASopathy models. This data also indicates that the primary candidate mechanism for control of altered translation in these modes is through the altered expression of mTOR.
ContributorsHilbert, Alexander Robert (Author) / Newbern, Jason (Thesis director) / Olive, M. Foster (Committee member) / Bjorklund, Reed (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
An increasing number of veterans are transitioning from military service to college. Critical to academic success is the process of decision-making, which previous research has found to be influenced by a variety of factors including anxiety and working memory (WM). Many service-related conditions often influence anxiety and WM, and given the high prevalence of these conditions among veterans, the present study aimed to analyze the effects of working memory and anxiety on decision-making behavior in U.S. Military Veterans. Participants completed a large test battery including tasks assessing WM skills (Symmetry Span Task), anxiety (Beck Anxiety Inventory), and decision-making (Iowa Gambling Task). The study results indicated that WM and anxiety both play roles in decision-making performance in young military veterans. High anxiety is related to increased avoidance of adverse outcomes in decision-making for U.S. Military Veterans, while lower working memory span is associated with greater risk-taking behavior. This study provides both functional and clinical implications into areas of possible intervention that need to be assessed in military veterans, as well as modifications to these assessments that need to be made in order to appropriately measure decision-making behavior. Future work will be done in order to more effectively analyze the adverse impacts of service-related conditions and the ways in which intervention can be implemented in order to minimize these effects.
ContributorsTully, Mckayla Lynne (Author) / Azuma, Tamiko (Thesis director) / Gallagher, Karen (Committee member) / Department of Psychology (Contributor) / Sanford School of Social and Family Dynamics (Contributor) / Department of Speech and Hearing Science (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
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 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.
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.
ContributorsCleveland, Alexandra (Author) / Gray, Shelley (Thesis director) / Azuma, Tamiko (Committee member) / College of Health Solutions (Contributor) / Barrett, The Honors College (Contributor)
Created2019-12