Matching Items (32)
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Description
It is commonly known that the left hemisphere of the brain is more efficient in the processing of verbal information, compared to the right hemisphere. One proposal suggests that hemispheric asymmetries in verbal processing are due in part to the efficient use of top-down mechanisms by the left hemisphere. Most

It is commonly known that the left hemisphere of the brain is more efficient in the processing of verbal information, compared to the right hemisphere. One proposal suggests that hemispheric asymmetries in verbal processing are due in part to the efficient use of top-down mechanisms by the left hemisphere. Most evidence for this comes from hemispheric semantic priming, though fewer studies have investigated verbal memory in the cerebral hemispheres. The goal of the current investigations is to examine how top-down mechanisms influence hemispheric asymmetries in verbal memory, and determine the specific nature of hypothesized top-down mechanisms. Five experiments were conducted to explore the influence of top-down mechanisms on hemispheric asymmetries in verbal memory. Experiments 1 and 2 used item-method directed forgetting to examine maintenance and inhibition mechanisms. In Experiment 1, participants were cued to remember or forget certain words, and cues were presented simultaneously or after the presentation of target words. In Experiment 2, participants were cued again to remember or forget words, but each word was repeated once or four times. Experiments 3 and 4 examined the influence of cognitive load on hemispheric asymmetries in true and false memory. In Experiment 3, cognitive load was imposed during memory encoding, while in Experiment 4, cognitive load was imposed during memory retrieval. Finally, Experiment 5 investigated the association between controlled processing in hemispheric semantic priming, and top-down mechanisms used for hemispheric verbal memory. Across all experiments, divided visual field presentation was used to probe verbal memory in the cerebral hemispheres. Results from all experiments revealed several important findings. First, top-down mechanisms used by the LH primarily used to facilitate verbal processing, but also operate in a domain general manner in the face of increasing processing demands. Second, evidence indicates that the RH uses top-down mechanisms minimally, and processes verbal information in a more bottom-up manner. These data help clarify the nature of top-down mechanisms used in hemispheric memory and language processing, and build upon current theories that attempt to explain hemispheric asymmetries in language processing.
ContributorsTat, Michael J (Author) / Azuma, Tamiko (Thesis advisor) / Goldinger, Stephen D (Committee member) / Liss, Julie M (Committee member) / Arizona State University (Publisher)
Created2013
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Description
The benefits of exercise have been recommended in typical and other special populations. However, the evidence for persons with Down syndrome (DS) is still limited. This study was aimed at investigating the impact of an acute bout of aerobic exercise intervention on motor performance, executive function and intrinsic motivation in

The benefits of exercise have been recommended in typical and other special populations. However, the evidence for persons with Down syndrome (DS) is still limited. This study was aimed at investigating the impact of an acute bout of aerobic exercise intervention on motor performance, executive function and intrinsic motivation in adolescents and young adults with DS. Ten participants with DS were assigned to an exercise group, who walked on a incremental treadmill protocol for 20 minutes. The exercise intensity was achieved at 66% of their predicted maximum heart rate. Another ten participants with DS were assigned to an attentional control group, who watched a video for 20 minutes. Measures of fine manual dexterity (e.g., Purdue Pegboard test), manual force production (e.g., grip strength test), processing speed (e.g., visual choice reaction time test), verbal processing (e.g., verbal fluency test), attention shifting ability (e.g., The Dimensional Card sorting test), and inhibitory control (e.g., Knock and Tap test) were tested pre and post intervention. An intrinsic motivation scale (e.g., enjoyment and effort) was conducted after the intervention. First, results showed participants significantly improved their performance in manual force production and Knock and Tap Test after the exercise intervention. While it has been proposed that exercise increases arousal status, neurotransmitters, or cerebral vasculature, the exact mechanisms in persons with DS are still unknown. However, our results showed that after treadmill walking, motor and cognitive improvements can be found in individuals with DS, even in a single exercise session. In addition, participants reported higher scores in enjoyment after video viewing than exercise, which may a result from musical effect or too much emphasis on external rewards in their early participation in exercise. These may imply that participants had low intrinsic motivation to an active lifestyle. Further, scores in effort were significantly higher after exercise than video viewing, which indicated their capabilities to perceive their physical exertion. However, other motivational regulations (e.g., introjected and identified regulations) have shown the relationship with exercise behavior in this population. Thus, further study should consider divergent motivational factors in order to implement an effective exercise program.
ContributorsChen, Chih-Chia (Author) / Ringenbach, Shannon D.R. (Thesis advisor) / Crews, Debra (Committee member) / Kulinna, Pamela (Committee member) / Amazeen, Eric (Committee member) / Arizona State University (Publisher)
Created2013
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Description
This study examines the relations among three aspects of temperament (shyness, impulsivity, and effortful control), resting respiratory sinus arrhythmia (RSA) recorded during a calming film and RSA suppression during three behavioral measures of effortful control, and adjustment (anxiety and externalizing behavior) in a sample of 101 preschool-age children. Principal components

This study examines the relations among three aspects of temperament (shyness, impulsivity, and effortful control), resting respiratory sinus arrhythmia (RSA) recorded during a calming film and RSA suppression during three behavioral measures of effortful control, and adjustment (anxiety and externalizing behavior) in a sample of 101 preschool-age children. Principal components analysis was used to create composites for effortful control, shyness, impulsivity, anxiety, and externalizing behavior, and hierarchical regression analysis was used to test the study hypotheses. As expected, baseline RSA was negatively related to effortful control in shy children, but was unrelated to effortful control in children who were not shy. It was hypothesized that high baseline RSA would reduce the relation between shyness and anxiety, and between impulsivity and externalizing behavior; this hypothesis was supported for externalizing behavior, but not for anxiety. The interaction between impulsivity and RSA as a predictor of externalizing was statistically independent of effortful control, indicating that these are unique effects. Finally, it was hypothesized that RSA suppression would be positively related to effortful control for children low, but not high, in shyness. There was a marginal interaction between shyness and RSA suppression, with RSA suppression marginally negatively related to EC for children low in shyness, but unrelated to effortful control for children high in shyness; the direction of this association was opposite predictions. These findings indicate that RSA is more strongly related to effortful control for children high in shyness, and that it consequently may not be appropriate to use RSA as an index of EC for all children. This study also draws attention to the need to consider the context in which baseline RSA is measured because a true baseline may not be obtained for shy children if RSA is measured in an unfamiliar laboratory context. The finding that high RSA moderated (but did not eliminate) the relation between impulsivity and externalizing behavior is consistent with the conceptualization of RSA as a measure of self-regulation, but further research is needed to clarify the mechanism underlying this effect.
ContributorsSulik, Michael John (Author) / Eisenberg, Nancy (Thesis advisor) / Spinrad, Tracy L. (Committee member) / Lemery-Chalfant, Kathryn (Committee member) / Arizona State University (Publisher)
Created2012
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Description
Poor executive cognitive functioning (ECF) is associated with a variety of alcohol-related problems, however, it is not known whether poor ECF precedes the onset of heavy drinking. Establishing the temporal precedence of poor ECF may have implications for our understanding of the development of Alcohol Use Disorder (AUD). The present

Poor executive cognitive functioning (ECF) is associated with a variety of alcohol-related problems, however, it is not known whether poor ECF precedes the onset of heavy drinking. Establishing the temporal precedence of poor ECF may have implications for our understanding of the development of Alcohol Use Disorder (AUD). The present study tests associations between early-adolescent ECF and young-adult risky drinking and alcohol-related problems in a prospective study of youth followed to young adulthood. Participants completed three ECF tasks at ages 11-14 and reported on their risky drinking and alcohol-related problems at ages 18-24. A latent ECF factor was created to determine whether early-adolescent ECF was associated with drinking outcomes after controlling for relevant covariates (e.g., age, sex, family history of AUD). Early-adolescent ECF, as measured by a latent factor, was unrelated to young-adult alcohol misuse and alcohol-related problems. However, sensitivity analyses revealed that an individual ECF task tapping response inhibition predicted young-adult peak drinks in a day. Present findings suggest that ECF is not a robust predictor of risky drinking or alcohol-related problems, and that this relation may be specific to the ECF component of response inhibition.
ContributorsJones, Connor Brian (Author) / Meier, Madeline (Thesis advisor) / Chassin, Laurie (Committee member) / McClure, Samuel (Committee member) / Arizona State University (Publisher)
Created2017
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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

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
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Description
This study examines cognitive planning in adolescents with Down syndrome (DS) following an 8-week assisted cycling therapy intervention. Forty-three participants were randomly assigned to assisted cycling (AC) (i.e., at least 30% faster than self-selected cadence accomplished by a motor), voluntary cycling (VC) (self-selected cadence), and no cycling (NC) control group.

This study examines cognitive planning in adolescents with Down syndrome (DS) following an 8-week assisted cycling therapy intervention. Forty-three participants were randomly assigned to assisted cycling (AC) (i.e., at least 30% faster than self-selected cadence accomplished by a motor), voluntary cycling (VC) (self-selected cadence), and no cycling (NC) control group. Both AC and VC rode a stationary bicycle three times/week, 30 minutes/session, for eight weeks in duration. Participants completed cognitive testing that assessed cognitive planning at the beginning (i.e., pretest) and end (i.e., posttest) of the 8-week intervention. Consistent with our hypothesis, the results showed that cognitive planning improved following eight weeks of cycling for the AC group. The same results were not seen for individuals in the VC or NC groups. Our results suggest that assisted cycling therapy may induce permanent changes in the prefrontal cortex in adolescents with DS.
ContributorsMillar, Kelsey Leann (Author) / Ringenbach, Shannon (Thesis director) / Amazeen, Eric (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2015-05
Description
Adaptive behavior consists of the social, conceptual and practical skills an individual must execute to function independently in their everyday life. Individuals with Down syndrome have limitations in their adaptive behavior due to cognitive and physical deficits. The aim of this study was to examine if an exercise program would

Adaptive behavior consists of the social, conceptual and practical skills an individual must execute to function independently in their everyday life. Individuals with Down syndrome have limitations in their adaptive behavior due to cognitive and physical deficits. The aim of this study was to examine if an exercise program would improve the adaptive behavior skills in persons with Down syndrome. The exercise intervention, Exercise for Adults with Down Syndrome (ExDS), was a semester long program where adults with Down syndrome participate in twice weekly workouts planned and executed by Arizona State University students. The workouts consisted of an aerobic warm up, aerobic exercises, resistance exercises, balance exercises and stretches. The participants' adaptive behavior and cognitive planning ability were assessed before ExDS and after ExDS. The Adaptive Behavior Assessment System Second Edition (ABAS-II) was used to measure adaptive behavior. The ABAS-II consisted of a forum that addressed the Social, Conceptual and Practical domains of adaptive behavior and was filled out by the participants' caregiver. The Tower of London (ToL) was used to measure cognitive planning ability. The change in the ABAS-II scores from pre- to post-testing were statistically insignificant. The change from pre- to post-testing in the ToL scores approached statistical significance. Limitations included bias caregiver perception and respondent inconsistency. There is a need for further research on the effect of exercise on the adaptive behavior in adults with Down syndrome.
ContributorsRoss, Alexandra Jill (Author) / Holzapfel, Simon (Thesis director) / Ringenbach, Shannon (Committee member) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
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Description
This study examines the one month retention of executive function benefits gained by adolescents with Down syndrome after an 8-week aerobic exercise intervention. Sixteen participants were randomly divided between voluntary (VC) (i.e., self-selected cadence) and assisted (AC) (i.e., 30% faster than self-selected cadence accomplished by a motor) cycling groups, with

This study examines the one month retention of executive function benefits gained by adolescents with Down syndrome after an 8-week aerobic exercise intervention. Sixteen participants were randomly divided between voluntary (VC) (i.e., self-selected cadence) and assisted (AC) (i.e., 30% faster than self-selected cadence accomplished by a motor) cycling groups, with one participant used as a control (NC). Both cycling groups rode a stationary bicycle, for 30 minutes, three times a week, for eight weeks. At the beginning (i.e., pretest) and end (posttest) of the 8-week session, three executive functions including: set-switching, inhibition, and cognitive planning, were tested. Approximately one month after the posttest, all participants underwent the cognitive testing again. The results showed that for the AC group cognitive planning improved after eight weeks of assisted cycling and these improvements were maintained after one month of no cycling. However, no significant differences were found between the cycling groups for our measure of inhibition. Set-switching appeared to be improved by both types of exercise, rather than only assisted, but the improvements were not maintained during the one month retention period for either group. Thus, our results suggest that Assisted Cycling causes potentially permanent changes in the brain in regards to cognitive planning.
ContributorsRichter, Madeline B. (Author) / Ringenbach, Shannon (Thesis director) / Amazeen, Eric (Committee member) / Maraj, Brian (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / School of Life Sciences (Contributor)
Created2014-05
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Description
The purpose of this study was to explore the effects of a four-week martial arts program implemented once a week on children diagnosed with attention-deficit hyperactivity disorder (ADHD) between the ages of four and seven. This was a single group, pre- and post-intervention assessment pilot study. The total sample of

The purpose of this study was to explore the effects of a four-week martial arts program implemented once a week on children diagnosed with attention-deficit hyperactivity disorder (ADHD) between the ages of four and seven. This was a single group, pre- and post-intervention assessment pilot study. The total sample of the study was four children (n=4) and the martial arts classes were based on the Duke Kenpo Little Tiger Program by Jonathan Duke of Mesa, Arizona. Change was measured using the Behavior Rating Inventory of Executive Function, 2nd edition (BRIEF-2) parental form and participants were encouraged to record at-home practice. Data were collected pre-intervention and four weeks afterwards. Limitations included small sample size, measurement limitation (e.g., ceiling effect), data based on parental report, a short intervention period, potential instructor bias, and uneven gender distribution. Given the small sample size (n=4), this study did not complete statistical analysis and alternatively described the changing patterns of the participant's ADHD symptoms from BRIEF-2 measures pre and post intervention. The results of this study could not generate the power to detect significance to state significant implications. However, the trends suggested that some participants declined in executive function in certain areas (e.g., task-monitoring and planning) and improved in other areas (e.g., working memory and organization of materials). All participants demonstrated improvement within the cognitive (CRI) scale of the BRIEF-2 and future studies may explore the potential for martial arts interventions in children under seven as a means to improve the cognitive aspect of executive function development. In addition, future studies may consider exploring the role of frequency versus time for at-home martial arts practice for children with ADHD under the age of seven.
ContributorsNaylor, Takara (Author) / Larkey, Linda (Thesis director) / Noah, Aggie (Committee member) / Arizona State University. College of Nursing & Healthcare Innovation (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
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Description
The aim of this study was to examine the influence of Assisted Cycling Therapy (ACT) on information processing measured by simple reaction time in older adults with Down Syndrome (DS). Twenty-one participants were randomly assigned to one of three interventions over eight weeks. 1) Eleven older adults with Down Syndrome

The aim of this study was to examine the influence of Assisted Cycling Therapy (ACT) on information processing measured by simple reaction time in older adults with Down Syndrome (DS). Twenty-one participants were randomly assigned to one of three interventions over eight weeks. 1) Eleven older adults with Down Syndrome completed the ACT intervention, which is stationary cycling with the assistance of a motor to maintain a cadence at least 35% greater than voluntary cycling. 2) Eight older adults with Down Syndrome completed the voluntary cycling (VC) intervention and 3) two older adults with Down Syndrome were in our no cycling (NC) intervention. Both exercise groups participated in the eight-week, supervised exercise protocol for at least three, 30-minute sessions per week. None of our results reached conventional levels of significance. However, the greatest improvements in reaction time occurred following the voluntary cycling (VC) intervention. Our results are discussed with respect to physiological differences in older adults with DS that may limit improvements in executive function following exercise. These physiological differences and limitations include muscle atrophy and reduced perceptions, age related latency between motor cortex activation and onset of muscle activity, as well as general age related slowing in reaction time. Although it may be difficult to improve executive function in older adults with DS, we suggest other benefits to exercise which include improving social communication, gross motor skills, and exercise perception. Future research should continue to investigate the effects of exercise on multiple areas in older adults with DS with the hopes of improving quality of life.
ContributorsCahill, Colleen Mary (Author) / Ringenbach, Shannon (Thesis director) / Amazeen, Eric (Committee member) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05