Peters, Kevin R

Freezing of gait is a debilitating symptom affecting individuals with Parkinson's disease. Emerging evidence suggests freezing may represent a global motor control deficit beyond gait. We investigated freezing episodes in the upper limbs using spatially-constrained reaching tasks known to elicit freezing of gait. Fourteen people with Parkinson's disease and 13 controls completed reaching tasks under three spatial conditions with varying backgrounds. The tunnel condition produced the greatest kinematic disruptions. Despite people with Parkinson's disease showing significantly longer movement times and slower speeds, they were less accurate in their movements, suggesting observed differences reflect genuine motor control deficits rather than speed-accuracy trade-offs. The tunnel's narrow spatial constraints challenge the motor system's ability to maintain coordinated movement trajectories, with people with Parkinson's disease exhibiting increased trajectory variability. These findings demonstrate that freezing-like episodes extend beyond gait, supporting the hypothesis that freezing represents a global motor phenomenon in Parkinson's disease.

Author Keywords: freezing of gait, motor control, Parkinson's disease, reaching, upper limbs

Pharmacological cognitive enhancement is the use of prescription drugs to improve cognitive functioning in healthy individuals. Multiple ethical concerns have been raised by such use. The purpose of this project was to develop a reliable and valid measure to assess public attitudes about this issue. Participants were university students in Studies 1 (N = 465), 2 (N = 580) and 3 (N = 156). In Study 1 principal components analysis reduced the 90-item Attitudes Toward Pharmacological Cognitive Enhancement Scale to 42 items that loaded onto four components: Cheating/Unfairness, Motivation, Expected Benefits and Safety. Subscale scores differentiated users and nonusers. In Study 2 confirmatory factor analyses supported the model and statistically significant associations were found with related constructs such as attitudes toward performance-enhancing drugs, and prescription drug expectancies. In Study 3 test-retest reliability over a 3-week interval was above .70 for 3 of 4 subscales. Implications and future directions are discussed.

Author Keywords: attitudes, cognitive enhancement, nonmedical use of prescription drugs, scale development, smart drugs

This thesis aimed to explore students' perspectives on university exams in two studies. Using a phenomenological approach, Study 1 recruited 10 senior undergraduate students to participate in semi-structured interviews. A thematic analysis revealed key themes related to exam purpose, effectiveness, fairness, and emotional responses. These insights informed the development of a sequence model explaining how students form exam perceptions. Study 2 was a concurrent, embedded, correlational mixed-methods case study of sophomore Psychology students' (N = 35) experiences with a case-based take-home exam designed according to motivational design principles. Findings from this study highlight the associations between students' motivation orientation and motivational assessment features and students' positive experiences and perceptions of the exam. This thesis offers an informative framework for instructors aiming to promote student buy-in, while also meeting course learning outcomes and facilitating deeper engagement with assessments.

Author Keywords: alternative assessment, assessment design, learning outcomes, student motivation, university exams

Pharmacological cognitive enhancement is the use of prescription drugs to improve cognitive functioning in healthy individuals. Multiple ethical concerns have been raised by such use. The purpose of this project was to develop a reliable and valid measure to assess public attitudes about this issue. Participants were university students in Studies 1 (N = 465), 2 (N = 580) and 3 (N = 156). In Study 1 principal components analysis reduced the 90-item Attitudes Toward Pharmacological Cognitive Enhancement Scale to 42 items that loaded onto four components: Cheating/Unfairness, Motivation, Expected Benefits and Safety. Subscale scores differentiated users and nonusers. In Study 2 confirmatory factor analyses supported the model and statistically significant associations were found with related constructs such as attitudes toward performance-enhancing drugs, and prescription drug expectancies. In Study 3 test-retest reliability over a 3-week interval was above .70 for 3 of 4 subscales. Implications and future directions are discussed.

Author Keywords: attitudes, cognitive enhancement, nonmedical use of prescription drugs, scale development, smart drugs

The present study examined the role of multiple nights of sleep in the consolidation of a complex motor learning task. Participants were 24 Trent undergraduates, 12 in the learning group (Mage = 20.33, SD = 1.87, 10 female) and 12 in the control group (Mage = 21.92, SD = 3.42, 7 female). Participants underwent 5 consecutive nights of polysomnographic recordings, with a Rock Band learning session on the third night. A series of 2(group)x4(night) ANOVAs were performed on the sleep variables. Interactions were found in the number of spindles detected at Pz, F(333) = 9.19, p <.01, and in the density of spindles detected at Pz, F(3,33) = 4.06, p <.05. The pattern of changes from baseline was significantly different between the two groups; spindles increased in the learning group and decreased in the control group. The novel finding was that spindle number/density remained elevated at the third post-learning night of sleep.

Author Keywords: Motor Learning, Procedural Memory, Sleep, Sleep Spindles