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- Creators: Department of Psychology
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Description
Motor behavior is prone to variable conditions and deviates further in disorders affecting the nervous system. A combination of environmental and neural factors impacts the amount of uncertainty. Although the influence of these factors on estimating endpoint positions have been examined, the role of limb configuration on endpoint variability has been mostly ignored. Characterizing the influence of arm configuration (i.e. intrinsic factors) would allow greater comprehension of sensorimotor integration and assist in interpreting exaggerated movement variability in patients. In this study, subjects were placed in a 3-D virtual reality environment and were asked to move from a starting position to one of three targets in the frontal plane with and without visual feedback of the moving limb. The alternating of visual feedback during trials increased uncertainty between the planning and execution phases. The starting limb configurations, adducted and abducted, were varied in separate blocks. Arm configurations were setup by rotating along the shoulder-hand axis to maintain endpoint position. The investigation hypothesized: 1) patterns of endpoint variability of movements would be dependent upon the starting arm configuration and 2) any differences observed would be more apparent in conditions that withheld visual feedback. The results indicated that there were differences in endpoint variability between arm configurations in both visual conditions, but differences in variability increased when visual feedback was withheld. Overall this suggests that in the presence of visual feedback, planning of movements in 3D space mostly uses coordinates that are arm configuration independent. On the other hand, without visual feedback, planning of movements in 3D space relies substantially on intrinsic coordinates.
ContributorsRahman, Qasim (Author) / Buneo, Christopher (Thesis director) / Helms Tillery, Stephen (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
Motor behavior is prone to variable conditions and deviates further in disorders affecting the nervous system. A combination of environmental and neural factors impacts the amount of uncertainty. Although the influence of these factors on estimating endpoint positions have been examined, the role of limb configuration on endpoint variability has been mostly ignored. Characterizing the influence of arm configuration (i.e. intrinsic factors) would allow greater comprehension of sensorimotor integration and assist in interpreting exaggerated movement variability in patients. In this study, subjects were placed in a 3-D virtual reality environment and were asked to move from a starting position to one of three targets in the frontal plane with and without visual feedback of the moving limb. The alternating of visual feedback during trials increased uncertainty between the planning and execution phases. The starting limb configurations, adducted and abducted, were varied in separate blocks. Arm configurations were setup by rotating along the shoulder-hand axis to maintain endpoint position. The investigation hypothesized: 1) patterns of endpoint variability of movements would be dependent upon the starting arm configuration and 2) any differences observed would be more apparent in conditions that withheld visual feedback. The results indicated that there were differences in endpoint variability between arm configurations in both visual conditions, but differences in variability increased when visual feedback was withheld. Overall this suggests that in the presence of visual feedback, planning of movements in 3D space mostly uses coordinates that are arm configuration independent. On the other hand, without visual feedback, planning of movements in 3D space relies substantially on intrinsic coordinates.
ContributorsRahman, Qasim (Author) / Buneo, Christopher (Thesis director) / Helms Tillery, Stephen (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
The degree to which adolescents describe themselves as gender typical, as defined by their interests, activities, personal qualities, and other characteristics, is related to a broad range of adjustment indices. The goal of this thesis was to review studies conducted between 2000 and 2017 to provide a summary and critique of this research. A total of 18 studies were reviewed. The majority of findings indicate a positive association between gender typicality and beneficial adjustment outcomes, and a negative association between gender typicality and poor adjustment outcomes. Suggestions for future research and clinical implications of these findings are discussed.
ContributorsCohen, Alexandra Danielle (Author) / Updegraff, Kimberly (Thesis director) / Miller, Cindy (Committee member) / College of Integrative Sciences and Arts (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Cultural beliefs and behaviors can serve as both risk and protective processes for Latino adolescents, with some recent empirical work suggesting the important protective role of bicultural values (e.g., endorsing high levels of both mainstream culture and culture of origin). We expanded on past research to explore whether bicultural values were associated with internalizing (depressive, anxiety, stress) symptoms and externalizing (alcohol use) symptoms among a sample of Latino adolescents preparing to begin college. We hypothesized biculturalism to protect against all negative outcomes. Our sample consisted of 209 college-bound Latino adolescents (65% female; 85.1% Mexican descent; 10.6% 1st generation, 62% 2nd generation) who were enrolled in university for the coming fall. All multivariate models included sex, ethnicity, parent education, and immigrant generation status as covariates. Correlations and multivariate analyses revealed that higher bicultural values were associated with lower depressive symptoms, lower anxiety symptoms, lower stress, and greater alcohol use. Gender was shown to moderate the relationship between biculturalism and alcohol use. Overall, findings suggested that greater bicultural values were associated with lower endorsement of internalizing symptoms for all participants, but higher endorsement of alcohol use over the last year for the highly bicultural females. Biculturalism may be particularly protective for Latino adolescents who are preparing to attend college given the need for them to transition into an environment with high acculturative demands. However, our results also highlight that these bicultural females may be at greater risk for alcohol use and related problems.
ContributorsDilgert, Janice (Author) / Doane, Leah (Thesis director) / Thompson, Daisy (Committee member) / Department of Psychology (Contributor) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
The literature has consistently established levels of adolescent maladjustment well above national norms for both socioeconomic (SES) extremes (Lyman & Luthar 2014). Yet literature on positive adolescent adjustment, and its protective or even corrective factors is lacking (Eisenberg, Zhou, & Coller, 2001). This study examined the effects of gender and SES on parent attachment in relation to reports of prosocial behavior. Eleventh grade adolescents (N = 397) were recruited from two public high schools for academically-gifted students who were either high or low-level SES (i.e. the extremes). The students provided passive consent and answered questions on their demographics, perceived relationship with their parents, and tendency to behave in a prosocial manner. Multivariate analyses of variance and follow up analyses of variance were run by gender and SES to determine main effects for gender and SES on parent attachment and prosocial behavior. Regressions following preliminary correlations analyzed whether parental attachment predicted higher levels of adolescent prosocial behavior. Results demonstrated that females communicated with their mothers significantly more and reported higher levels of prosocial behavior than their male counterparts. Findings with regard to SES revealed that high SES adolescents reported increased parent attachment, whereas low SES adolescents reported higher levels of community\u2014based prosocial behaviors. Finally, certain dimensions of parent attachment predicted increases and decreases only in specific prosocial behaviors. Because prosocial behaviors change throughout adolescence, future ventures should consider a longitudinal analysis to obtain a more comprehensive picture of adolescent positive adjustment.
ContributorsAli, Hira (Author) / Luthar, Suniya (Thesis director) / Infurna, Frank (Committee member) / Davis, Mary (Committee member) / Department of Psychology (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
Depression, anxiety, and suicidal thoughts or actions are on the rise in adolescents (National Institute of Mental Health, 2015; Bridge, Asti, & Horowitz, 2015). Parents, school administrators, and therapists are searching for resiliency factors with in at-risk groups to aid students in need. In previous work, Luthar and Zigler (1992) reported that intelligent youth are more resilient than less intelligent youth under low stress conditions but they lose their advantage under high stress conditions. This study examined whether intelligence (reflected in grade point average; GPA) and maladaptive (internalizing and externalizing symptoms) behaviors are negatively related in adolescents, and tested whether level of stress, reflected in emotion regulation and friendship quality, moderated that association. It also probed whether the relationships differ by gender. Sixth-graders (N=506) were recruited with active parental consent from three middle schools. Adolescents completed self-report questionnaires Regarding demo graphics, maladaptive behaviors, emotion regulation, and friendship quality, and GPA data were collected from the school. Regression analyses found that GPA was negatively related to externalizing symptoms. Girls with poor friendship communication report significantly higher maladaptive behaviors. This relation was more pronounced for girls with high GPAs, as predicted. Results support the theory that intelligent female adolescents are more reactive under adverse circumstances. Future efforts should follow students through middle school into high school to evaluate whether friendships remain important to adjustment, hold for boys as well as girls, and have implications for relationship interventions.
ContributorsGonzales, Ashlyn Carol (Author) / Luthar, Suniya (Thesis director) / Davis, Mary (Committee member) / Infurna, Frank (Committee member) / Department of Psychology (Contributor) / Sanford School of Social and Family Dynamics (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
Marijuana is currently the mostly widely used illicit drug in the U.S., and has been for multiple decades (Johnston et. al., 2016). Despite a growing belief that marijuana use is not harmful, over 4 million Americans have met criteria for marijuana use disorders in the past year alone (CBHSQ, 2015). According to marijuana trajectory studies, about a third of marijuana users will end up quitting later in life, but some \u2014 such as those who meet criteria for dependence \u2014 have a much greater difficultly quitting. Therefore, by looking at marijuana users who were successful in quitting, and comparing them to ongoing adult marijuana users, factors that may assist in helping an individual quit \u2014 such as certain motivations for quitting \u2014 may be identified. To study these issues, data was collected from 507 participants from the Pittsburgh Youth Study. It was found that adolescents who used marijuana weekly for at least one year were likely to be ongoing marijuana users in adulthood and that adolescents who had a warm relationship with their primary caretaker were likely to have quit marijuana by adulthood. It was also found that Black participants were more likely to have legal, monetary, and religious reasons for quitting than were White participants. Furthermore, participants who used regularly in adolescence were likely to list legal reasons, as well as a concern that marijuana use was needed to feel normal. Finally, it was found that not a single motivation for quitting marijuana was associated with a shorter period of abstinence. The implications of these findings for motivations to quit marijuana are the focus of the discussion.
ContributorsGomez, Kira Elise (Author) / Pardini, Dustin (Thesis director) / Glenberg, Arthur (Committee member) / Meier, Madeline (Committee member) / Department of Psychology (Contributor) / School of Art (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Research on joint control during arm movements in adults has led to the development of the Leading Joint Hypothesis (LJH), which states that the central nervous system takes advantage of interaction torque (IT) and muscle torque (MT) to produce movements with maximum efficiency in the multi-jointed limbs of the human body. A gap in knowledge exists in determining how this mature pattern of joint control develops in children. Prior research focused on the kinematics of joint control for children below the age of three; however, not much is known about interjoint coordination with respect to MT and IT in school-aged children. In the present study, joint control at the shoulder, elbow, and wrist during drawing of five shapes was investigated. A random sample of nine typically developing children ages 6 to 12 served as subjects. The task was to trace with the index finger a template placed on a horizontal table. The template consisted of a circle, horizontal, vertical, right-diagonal, and left-diagonal line. Analysis of muscle torque contribution (MTC) revealed the individual roles of MT and IT in the shoulder, elbow, and wrist joints. During drawing of the horizontal line, which requires the most difficult joint control pattern in adults because it does not allow the use of IT for joint rotation, joint control was found to change through development. For the youngest children, the function of elbow MT modified to suppress IT, thereby producing large elbow rotation. The oldest children simplified this by using the shoulder as the principal joint of movement production and with decreased assistance from the elbow. For the other four drawing movements, differences in the pattern of joint control used by all of the subjects was unaffected by an increase in age. Overall, the results suggest that in children above 6 years of age, minor changes in joint control occur during drawing of relatively simple movements. The limited effect of age that was observed could be related to the restriction of movements to the horizontal plane. For a future study, three-dimensional movements that provide more freedom in joint control due to redundancy of degrees of freedom could be more informative about developmental changes in joint coordination.
ContributorsKemmou, Nadaa (Co-author) / Way, Victoria (Co-author) / Dounskaia, Natalia (Thesis director) / Vidt, Meghan (Committee member) / School of Nutrition and Health Promotion (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
The premise of the embodied cognition hypothesis is that cognitive processes require emotion, sensory, and motor systems in the brain, rather than using arbitrary symbols divorced from sensorimotor systems. The hypothesis explains many of the mechanisms of mental simulation or imagination and how they facilitate comprehension of concepts. Some forms of embodied processing can be measured using electroencephalography (EEG), in a particular waveform known as the mu rhythm (8-13 Hz) in the sensorimotor cortex of the brain. Power in the mu band is suppressed (or de-synchronized) when an individual performs an action, as well as when the individual imagines performing the action, thus mu suppression measures embodied imagination. An important question however is whether the sensorimotor cortex involvement while reading, as measured by mu suppression, is part of the comprehension of what is read or if it is arises after comprehension has taken place. To answer this question, participants first took the Gates-MacGinitie reading comprehension test. Then, mu-suppression was measured while participants read experimental materials. The degree of mu-suppression while reading verbs correlated .45 with their score on the Gates-MacGinitie test. This correlation strongly suggests that the sensorimotor system involvement while reading action sentences is part of the comprehension process rather than being an aftereffect.
ContributorsMarino, Annette Webb (Author) / Glenberg, Arthur (Thesis director) / Presson, Clark (Committee member) / Blais, Chris (Committee member) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
The thesis project merges interdisciplinary research to develop a self-directed creative intervention for immigrant youth, allowing them to make sense of their social and cultural identities. It takes research on self-awareness, multicultural identification, perceived belonging, and bibliotherapy to create a guided journal titled "Unearth," filled with art and writing prompts that are age-appropriate for adolescents and that serve as avenues for self-exploration. The project ultimately engages a focus group discussion to understand the usability and accessibility of the intervention.
ContributorsDizon, Arni Elyz (Co-author) / Nawrocki, Andie (Co-author) / Pina, Armando (Thesis director) / Benoit, Renee (Committee member) / Causadias, Jose (Committee member) / Department of Psychology (Contributor) / School of Social Transformation (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05