Mechanisms of Timing Across Tasks and Temporal Intervals.

This dissertation investigates whether the information-processing instantiation of scalar expectancy theory (SET) is responsible for timing durations that span both the milliseconds and seconds ranges across perceptual and motor timing tasks. A common-timer view predicts that variability increases proportionally with increasing duration in a similar fashion across tasks. We use the coefficient of variation as an estimate of temporal sensitivity, and we perform Weber slope analysis to compare estimates of duration-dependent variance across durations and tasks. Other dependent variables included measures of temporal accuracy and response latency. Experiment 1 investigated whether a common mechanism can account for performance across a range of durations within a temporal reproduction task. The results were inconsistent with a single scalar timer across durations. Experiment 2 involved using endpoint pairs to reduce anchoring effects, a larger number of stimulus durations, and the addition of a similarly structured task that emphasized perception. Temporal reproduction and discrimination tasks were run in different subject groups, and again, the data challenge a single scalar timer within reproduction and point to separate timers for the two tasks. The third experiment examined the similarly structured temporal reproduction and discrimination tasks in a within-subjects design, eliminating the procedural differences between the tasks present in Experiment 2, and allowing for analysis of individual differences. The data again revealed nonlinear timing in the two tasks as well as evidence for task-specific clocks. Overall, these data argue against the possibility of a single scalar timer across durations in motor and perceptual timing and suggest a reformulation of the processes responsible for timing in these task conditions.Ph.D.PsychologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/57725/2/abangert_1.pd

Physical and functional fitness changes in older adults in response to a traditional training program and a Wii enhanced training program

The Wii Fit Plus Balance program has been recommended as an alternative training tool for older adults to improve physical and functional fitness. However, the effectiveness of the Wii Fit Plus in combination with traditional training approaches in older adults is unclear. PURPOSE: To compare changes in physical fitness measures in older adults (OA) engaging in two different training programs: 1) traditional exercises performed by the control group (CG) and 2) traditional exercises complemented by Wii balance games performed by the experimental group (EG). METHODS: 35 untrained OA (mean ± SD Age: 68.86 ± 6.13; BMI: 28.89 ± 5.32) with no exercise history were recruited and randomly assigned to either the CG or EG group. CG and EG programs both included cardio, strength, flexibility, and balance training exercises. However, subjects in the EG group performed additional balance exercises using Wii fit plus program. Both CG and EG subjects exercised twice per week for twelve weeks. Fitness assessments were based on standard procedures including the chair stand, gallon jug transfer, 8 foot up-and-go tests, as well as a long ramp walk and medicine ball throw tests. Data were collected at weeks 1, 6, and 12. Data analysis was conducted using the general linear mixed model with alpha level set at p\u3c0.05. RESULTS: A significant time effect was found for all fitness measures in both groups from week 1 to 6 (p\u3c0.001) and week 1 to 12 (p\u3c0.001). In general CG and EG subjects made 5.5% to 31.7% improvement from Week 1 to 6 and 8.1% to 52.5% improvement from Week 1 to 12. No significant group effects were observed between the CG and EG groups (p\u3e0.370). Also, no significant group by time interactions were observed for any of the fitness measures (p\u3e0.290). CONCLUSION: It appears that the use of the Wii Fit Plus Balance in conjunction with a traditional exercise program does not provide added significant fitness benefits for older adults. While additional fitness benefits are not evident, it appears that both a traditional exercise program alone and a traditional exercise program combined with the Wii Fit Plus Balance training may elicit significant fitness improvements

Perspectives of Interactions with Healthcare Providers Among Patients Who Are Blind

Healthcare providers’ (HCPs) stereotypes about the incompetence of blind and low-vision patients may lead them to patronize blind patients, over-focus on impairments, and neglect the presenting problem. The content of perceived HCP stereotypes about blind patients in the clinical setting was examined from the patient perspective with seven focus groups, including a total of 42 individual participants. Most participants reported an interaction when their HCPs treated them as if they were incompetent, and discussed how perceived evaluations of their warmth and competence impacted whether their HCPs trusted and respected them. Participants also discussed their evaluations of their HCPs’ warmth and competence, and how these evaluations impacted their trust and respect for the HCP. These results provide insight into blind patients’ experiences interacting with their HCPs and can inform interventions to 1) help HCPs avoid stereotypic attitudes and 2) improve HCPs’ comfort and abilities when working with patient with disabilities

On the spontaneous discovery of a mathematical relation during problem solving

People spontaneously discover new representations during problem solving. Discovery of a mathematical representation is of special interest, because it shows that the underlying structure of the problem has been extracted. In the current study, participants solved gear-system problems as part of a game. Although none of the participants initially used a mathematical representation, many discovered a parity-based, mathematical strategy during problem solving. Two accounts of the spontaneous discovery of mathematical strategies were tested. According to the automatic schema abstraction hypothesis, experience with multiple, unique problem exemplars facilitates extraction of the parity relation. According to the comparison-based abstraction hypothesis, explicitly comparing gear pathways that have different number, but the same parity, should result in extraction of parity. An event history analysis showed that accumulation of experiences with different-number, same-parity comparisons predicted discovery of parity; accumulation of unique exemplars did not. Results suggest that comparison-based abstraction processes can lead to the discovery of a mathematical relation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74539/1/s15516709cog2803_6.pd