Top-down and Bottom-up influences on ACC activation: Evaluation of a proposed model of the feedback-related negativity

The Feedback-Related Negativity (FRN) is thought to reflect the dopaminergic prediction error signal from the subcortical areas to the ACC (i.e., a bottom-up signal). Two studies were conducted in order to test a new model of FRN generation, which includes direct modulating influences of medial PFC (i.e., top-down signals) on the ACC at the time of the FRN. Study 1 examined the effects of one’s sense of control (top-down) and of informative cues (bottom-up) on the FRN measures. In Study 2, sense of control and instruction-based (top-down) and probability-based expectations (bottom-up) were manipulated to test the proposed model. The results suggest that any influences of medial PFC on the activity of the ACC that occur in the context of incentive tasks are not direct. The FRN was shown to be sensitive to salient stimulus characteristics. The results of this dissertation partially support the reinforcement learning theory, in that the FRN is a marker for prediction error signal from subcortical areas. However, the pattern of results outlined here suggests that prediction errors are based on salient stimulus characteristics and are not reward specific. A second goal of this dissertation was to examine whether ACC activity, measured through the FRN, is altered in individuals at-risk for problem-gambling behaviour (PG). Individuals in this group were more sensitive to the valence of the outcome in a gambling task compared to not at-risk individuals, suggesting that gambling contexts increase the sensitivity of the reward system to valence of the outcome in individuals at risk for PG. Furthermore, at-risk participants showed an increased sensitivity to reward characteristics and a decreased response to loss outcomes. This contrasts with those not at risk whose FRNs were sensitive to losses. As the results did not replicate previous research showing attenuated FRNs in pathological gamblers, it is likely that the size and time of the FRN does not change gradually with increasing risk of maladaptive behaviour. Instead, changes in ACC activity reflected by the FRN in general can be observed only after behaviour becomes clinically maladaptive or through comparison between different types of gain/loss outcomes.

Words on wisdom: perspective transformation in a "learning in retirement institute" /

In this study, 7 men and women with an average age of 77 were interviewed regarding their experience of attending courses at a Learning in Retirement Institute (LRI) in southern Ontario. The purpose was to explore the role of wisdom in the learning of these retirees. Explicit theories of wisdom developed by selected philosophers, psychologists, and religious thinkers were compared to the implicit theories of wisdom that respondents expressed. Further comparisons were drawn between these implicit theories of wisdom and the act of perspective transformation in transformative learning. Some evidence was found that the development of wisdom compares favourably to perspective transformation, especially with regards to the behavioural changes associated with critical self-reflection. Among all the respondents, those 3 LRI stude.its who had also moderated courses indicated that they had experienced the most opportunities for critical self-reflection. These 3 also expressed deep satisfaction in having been able to put their learnings to use as teachers. A recommendation of this study is that opportunities for sharing and acting upon the results of discourse within Learning in Retirement Institutes should be implemented. In the absence of evaluation, opportunities for praxis (such as coop placements) must be developed so that students can measure their success against objective criteria and hence attach meaning to their studies.

Towards Evaluating and Modelling the Impacts of Mobile-Based Augmented Reality Applications on Learning and Engagement

Mobile augmented reality applications are increasingly utilized as a medium for enhancing learning and engagement in history education. Although these digital devices facilitate learning through immersive and appealing experiences, their design should be driven by theories of learning and instruction. We provide an overview of an evidence-based approach to optimize the development of mobile augmented reality applications that teaches students about history. Our research aims to evaluate and model the impacts of design parameters towards learning and engagement. The research program is interdisciplinary in that we apply techniques derived from design-based experiments and educational data mining. We outline the methodological and analytical techniques as well as discuss the implications of the anticipated findings.