Theses and Dissertations
This collection includes both ASU Theses and Dissertations, submitted by graduate students, and the Barrett, Honors College theses submitted by undergraduate students.
Displaying 1 - 10 of 353
Filtering by
- All Subjects: Health
- All Subjects: Cognitive Psychology
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 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
Description
Perceptual learning by means of coherent motion training paradigms has been shown to produce plasticity in lower and higher-level visual systems within the human occipital lobe both supra- and subliminally. However, efficiency of training methods that produce consolidation in the visual system via coherent motion has yet to be experimentally determined. Furthermore, the effects of coherent motion training on reading comprehension, in clinical and normal populations, are still nascent. In the present study, 20 participants were randomly assigned to one of four experimental conditions. Two conditions had a participation requirement of four days while two conditions required eight days of participation. These conditions were further divided into 500 or 1000 trials per day (4 x 500, 4 x 1000, 8 x 500, 8 x 1000). Additional pre-test and post-test days were used to attain timed pre- and post-tests on the Wide Range Achievement Test IV (WRAT IV) reading comprehension battery. Furthermore, a critical flicker fusion threshold (CFFT) score was taken on a macular pigment densitometer on the pre-test and post-test day. Participants showed significant improvement in CFFT levels, WRAT IV reading comprehension, and speed of completion between pre-test and post-test; however, degree of improvement did not vary as a function of training condition. An interaction between training condition and degree of improvement was evident in coherent dot motion contrast scores, with significant training plasticity occurring in the 4 x 1000 and 8 x 500 conditions.
ContributorsGroth, Anthony (Author) / Náñez, José E. (Thesis advisor) / Hall, Deborah (Committee member) / Risko, Evan F. (Committee member) / Arizona State University (Publisher)
Created2013
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
When a rolling ball exits a spiral tube, it typically maintains its final inertial state and travels along straight line in concordance with Newton's first law of motion. Yet, most people predict that the ball will curve, a "naive physics" misconception called the curvilinear impetus (CI) bias. In the current paper, we explore the ecological hypothesis that the CI bias arises from overgeneralization of correct motion of biological agents. Previous research has established that humans curve when exiting a spiral maze, and college students believe this motion is the same for balls and humans. The current paper consists of two follow up experiments. The first experiment tested the exiting behavior of rodents from a spiral rat maze. Though there were weaknesses in design and procedures of the maze, the findings support that rats do not behave like humans who exhibit the CI bias when exiting a spiral maze. These results are consistent with the CI bias being an overgeneralization of human motion, rather than generic biological motion. The second experiment tested physics teachers on their conception of how a humans and balls behave when exiting a spiral tube. Teachers demonstrated correct knowledge of the straight trajectory of a ball, but generalized the ball's behavior to human motion. Thus physics teachers exhibit the opposite bias from college students and presume that all motion is like inanimate motion. This evidence supports that this type of naive physics inertial bias is at least partly due to participants overgeneralizing both inanimate and animate motion to be the same, perhaps in an effort to minimize cognitive reference memory load. In short, physics training appears not to eliminate the bias, but rather to simply shift it from the presumption of stereotypical animate to stereotypical inanimate behavior.
ContributorsDye, Rosaline (Author) / Mcbeath, Michael K (Thesis advisor) / Sanabria, Federico (Committee member) / Megowan, Colleen (Committee member) / Arizona State University (Publisher)
Created2013
Description
Magicians are informal cognitive scientists who regularly test their hypotheses in the real world. As such, they can provide scientists with novel hypotheses for formal psychological research as well as a real-world context in which to study them. One domain where magic can directly inform science is the deployment of attention in time and across modalities. Both magicians and scientists have an incomplete understanding of how attention operates in time, rather than in space. However, magicians have highlighted a set of variables that can create moments of visual attentional suppression, which they call "off-beats," and these variables can speak to modern models of temporal attention. The current research examines two of these variables under conditions ranging from artificial laboratory tasks to the (almost) natural viewing of magic tricks. Across three experiments, I show that the detection of subtle dot probes in a noisy visual display and pieces of sleight of hand in magic tricks can be influenced by the seemingly irrelevant rhythmic qualities of auditory stimuli (cross-modal attentional entrainment) and processes of working memory updating (akin to the attentional blink).
ContributorsBarnhart, Anthony S (Author) / Goldinger, Stephen D. (Thesis advisor) / Glenberg, Arthur M. (Committee member) / Homa, Donald (Committee member) / Simons, Daniel J. (Committee member) / Arizona State University (Publisher)
Created2013
Description
Bully victimization has been associated with blunted cardiovascular responses to stress as well as elevated responses to stress. The difference between these altered physiological responses to stress is largely unknown. This study explored several possible moderators to the relationship between chronic stress and future cardiac output (an indicator of increased stress) in response to future stressors. These moderators include the difference between social and physical stressors and individual levels of loneliness. Participants were administered measures of loneliness and victimization history, and led to anticipate either a "social" (recorded speech) or "non-social" (pain tolerance test ) stressor, neither of which occurred. EKG and impedance cardiography were measured throughout the session. When anticipating both stressors, loneliness and victimization were associated with increased CO. A regression revealed a three-way interaction, with change in cardiac output depending on victimization history, loneliness, and condition in the physical stressor condition. Loneliness magnified the CO output levels of non-bullied individuals when facing a physical stressor. These results suggest that non- bullied participants high in loneliness are more stressed out when facing stressors, particularly stressors that are physically threatening in nature.
ContributorsHaneline, Magen (Author) / Newman, Matt (Thesis advisor) / Salerno, Jessica (Committee member) / Miller, Paul (Committee member) / Arizona State University (Publisher)
Created2013
Description
Purpose: This study examines the role of social support on adjustment to widowhood. Past research has indicated that the role of social support on adjustment to widowhood remains inconclusive, and needs further examination. This study examines the varying coping trajectories of middle-aged and retired bereaved spouses. Additionally, this study examines how bereavement stage may also influence one's adaptation to widowhood. Methods: This study used in-depth and semi-structured interviews as a means of understanding the role of social support on adjustment to widowhood. Participants were recruited through two hospice services available in a major metropolitan area in the United States. Convenient and purposive samplings are used in this study; this study will execute a grounded theory approach in order to determine the inconclusive role of social support on adjustment to widowhood. This study is contrasting between two stages- life course stages (middle aged versus retirement aged people) and bereavement stages (a year or less time following the death of a spouse versus three or more years following the death of a spouse). As a means of reducing bias and subjectivity, all data collected during the interview will be transcribed immediately. Results: Middle-aged bereaved spouses reported higher levels of motivation for adjusting positively and quickly towards widowhood due to their concern for protecting the well-being of their surviving young children compared to retired bereaved spouses. Differences between middle-aged widows and widowers have been found in this study; middle-aged widowers have a higher linkage to negative health behaviors. Retired bereaved spouses may fare better depending upon their housing location. Living in a retirement center may lower negative effects of bereavement on retired spouses' health. Conclusions: Types of social support received and expected varied between middle-aged widows and widowers. Gender norms may influence the type of social support widows and widowers receive. Middle-aged widowers are less likely to receive emotional support which may explain their higher linkage to negative health behaviors. Bereavement stage and housing location may be the key factors that influence widowhood trajectories of retired bereaved spouses. Living in a retirement center may lower the negative effects of bereavement on overall health.
ContributorsRafieei, Noshin (Author) / Kronenfeld, Jennie (Thesis advisor) / Haas, Steven (Committee member) / Damgaard, Anni (Committee member) / Arizona State University (Publisher)
Created2013
Description
Research has demonstrated that temperature and relative humidity substantially influence overall perceptions of indoor air quality (Fang, Clausen, & Fanger, 1998). This finding places temperature quality as a high priority, especially for vulnerable adults over 60. Temperature extremes and fluctuation, as well as the perception of those conditions, affect physical performance, thermal comfort and health of older adults (Chatonnet & Cabanac, 1965, pp. 185-6; Fumiharu, Watanabe, Park, Shephard, & Aoyagi, 2005; Heijs & Stringer, 1988). The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) and the International Organization for Standardization (ISO) have developed thermal-comfort standards for working-age, healthy individuals. None of these standards address the physiological and psychological needs of older adults (ASHRAE Standard 55, 2010; ISO-7730, 2005). This dissertation investigates the impacts of thermal conditions on self-reported health and perceived comfort for older adults, hypothesizing that warmer and more-table indoor thermal conditions will increase the health and perceived comfort of these adults. To this end, a new set of thermal comfort metrics was designed and tested to address the thermal preferences of older adults. The SENIOR COMFORT Metrics 2013 outlined new thresholds for optimal indoor high and low temperatures and set limits on thermal variability over time based on the ASHRAE-55 2010 model. This study was conducted at Sunnyslope Manor, a multi-unit, public-housing complex in the North Phoenix. Nearly 60% (76 of 118) of the residents (aged 62-82) were interviewed using a 110-question, self-reporting survey in 73 apartment units. A total of 40 questions and 20 sub-questions addressing perceptions of comfort, pain, sleep patterns, injuries, and mood were extracted from this larger health condition survey to assess health and thermal comfort. Indoor environmental thermal measurements included temperature in three locations: kitchen, living area, and bedroom and data were recorded every 15 minutes over 5 full days and 448 points. Study results start to indicate that older adults for Sunnyslope Manor preferred temperatures between 76 and 82.5 degrees Fahrenheit and that lower temperatures as outlined by ASHRAE-55 2010 increases the rate of injuries and mood changes in older adults among other findings.
ContributorsFonseca, Ernesto (Author) / Bryan, Harvey (Thesis advisor) / Ahrentzen, Sherry (Committee member) / Shea, Kimberly (Committee member) / Arizona State University (Publisher)
Created2013
Description
When people look for things in their environment they use a target template - a mental representation of the object they are attempting to locate - to guide their attention around a scene and to assess incoming visual input to determine if they have found that for which they are searching. However, unlike laboratory experiments, searchers in the real-world rarely have perfect knowledge regarding the appearance of their target. In five experiments (with nearly 1,000 participants), we examined how the precision of the observer's template affects their ability to conduct visual search. Specifically, we simulated template imprecision in two ways: First, by contaminating our searchers' templates with inaccurate features, and second, by introducing extraneous features to the template that were unhelpful. In those experiments we recorded the eye movements of our searchers in order to make inferences regarding the extent to which attentional guidance and decision-making are hindered by template imprecision. We also examined a third way in which templates may become imprecise; namely, that they may deteriorate over time. Overall, our findings support a dual-function theory of the target template, and highlight the importance of examining template precision in future research.
ContributorsHout, Michael C (Author) / Goldinger, Stephen D (Thesis advisor) / Azuma, Tamiko (Committee member) / Homa, Donald (Committee member) / Reichle, Erik (Committee member) / Arizona State University (Publisher)
Created2013
Description
As technology enhances our communication capabilities, the number of distributed teams has risen in both public and private sectors. There is no doubt that these technological advancements have addressed a need for communication and collaboration of distributed teams. However, is all technology useful for effective collaboration? Are some methods (modalities) of communication more conducive than others to effective performance and collaboration of distributed teams? Although previous literature identifies some differences in modalities, there is little research on geographically distributed mobile teams (DMTs) performing a collaborative task. To investigate communication and performance in this context, I developed the GeoCog system. This system is a mobile communications and collaboration platform enabling small, distributed teams of three to participate in a variant of the military-inspired game, "Capture the Flag". Within the task, teams were given one hour to complete as many "captures" as possible while utilizing resources to the advantage of the team. In this experiment, I manipulated the modality of communication across three conditions with text-based messaging only, vocal communication only, and a combination of the two conditions. It was hypothesized that bi-modal communication would yield superior performance compared to either single modality conditions. Results indicated that performance was not affected by modality. Further results, including communication analysis, are discussed within this paper.
ContributorsChampion, Michael (Author) / Cooke, Nancy J. (Thesis advisor) / Shope, Steven (Committee member) / Wu, Bing (Committee member) / Arizona State University (Publisher)
Created2012