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Effects of a Disengagement Intervention on Cognitive Performance in Those with a Mild Head Injury
Get PDFMild head injury (MHI) is a major public health concern and cognitive fatigue following injury is one of the most commonly reported and debilitating symptoms that interfere with everyday life. The ventromedial prefrontal cortex (vmPFC) is especially susceptible during injury and is an important brain region in the context of traumatic brain injury; the vmPFC is responsible for regulating physiological arousal and the neuropathology following MHI has been shown to lead to physiological underarousal. Dampened physiological arousal has been shown to precede and give rise to cognitive fatigue, and that more severe injuries lead to both worsened physiological arousal and fatigue outcomes. The frontal regions most susceptible during injury are also largely involved in attentional processes, such that attentional processes are compromised following the neuropathology associated with MHI as well as from the onset of cognitive fatigue. Attentional deficits then arise in those with a history of MHI as a function of injury as well as cognitive fatigue compounding together; these attentional deficits then go on to impair overall cognitive functions which then present as poor performance on cognitively demanding tasks and, or, as a lessened ability to make optimal decisions in everyday life. Due to this, physiological arousal may then reflect cognitive resources available to individuals, and an opportunity to replenish these cognitive resources (i.e., a disengagement intervention) may lead to better performance outcomes on cognitively demanding tasks as well as improved fatigue ratings. This study sought to examine the effects of a disengagement intervention on cognitive performance across cognitively demanding tasks (i.e., Go/No-Go Task and Mental Rotation Task [MR Task]) in those with, and without, a history of MHI. It was found that those with a history of MHI exhibited lower physiological arousal as a function of injury severity, higher fatigue, and required more effort to meet task demands. It was also found that the Go/No-Go Task reliably induced cognitive fatigue as evidenced by diminished performance as a function of time on task, and that the stimulus-driven Go/No-Go Task slowly depleted cognitive resources while the goal-directed MR Task quickly exhausted cognitive resources. It was also found that having the opportunity to disengage from the task for a short period of time buffered performance decrements and lead to requiring less effort across cognitively demanding tasks. Additionally, it was also found that physiological arousal was dampened and fatigue was heightened as a function of the lockdowns imposed by the COVID-19 pandemic
Effects of Red Rooibos on Mandibular Bone Structure in Sprague-Dawley Rats at 4 Months Post-Lactation
Get PDFPhysiological changes during pregnancy and lactation result in challenges to the maternal rodent skeleton. Red rooibos (RR) supplementation to rats was previously shown to support the recovery of tibia bone structure through to 4 months post-lactation. Given the associations between oral and systemic health, this research used multiple ROIs within the mandible to determine: if there are differences in trabecular bone structure at 4 months post-lactation compared to the non-pregnant control; the effects of a RR intervention administered from pre-pregnancy through 4 months post-lactation on trabecular bone structure compared to no RR intervention; and if measured outcomes are similar among groups regardless of the ROI studied. 6-week-old female Sprague-Dawley rats (n=42) were randomized to PREG TEA (pregnancy and lactation; supplemental level of RR in water ~2600 mg/kg body weight/day), PREG WAT (pregnancy and lactation; water), or GROWTH CON (non-pregnant control; water), bred at 8-weeks of age and maintained until 4 months post-lactation when mandibles were excised. Micro-computed tomography was used to measure bone structure at four ROIs: fixed shape or manually drawn ROI in molar 1 (M1) or molar 2 (M2) site. At M1, analyses using a fixed ROI demonstrated that PREG TEA had a higher bone volume fraction (p0.05), whereas PREG WAT had significantly lower (p<0.05) bone volume fraction and trabecular number than GROWTH CON. At M2, few significant
outcomes were observed regardless of ROI. This may be due to the lower amount of bone present at this site. Pregnancy and lactation resulted in deficits to mandible bone, but RR supplementation supported partial recovery, which aligns with previous findings for tibia. Findings can inform future research about which mandible site to select to measure a response to a dietary intervention
The current state is a crime: Decolonizing experiential education on the Brock University campus
Get PDFIndigenous ways of knowing and being have always been experiential. With this, our Canadian post-secondary institutions that have been working to grow experiential education and experiential learning opportunities have an obligation to acknowledge these Indigenous roots in order to avoid further appropriation. With two thirds of the Truth and Reconciliation Commission (TRC) of Canada’s 94 calls to action focused on education, including post-secondary, the Ontario Government has also recommended that post-secondary institutions in the province provide students with a minimum of two experiential learning opportunities within their academic courses by the time they graduate. This Participatory Action Research (PAR) project at Brock University was designed and executed in full collaboration with Indigenous peoples and looks at a campus with a focus on decolonization as well as experiential learning through an Appreciative Inquiry framework to best determine how experiential education can be decolonized. Using semi-structured interviews, focus groups, and institutional documents that speak to the current state of experiential learning as well as institutional strategic goals, ten themes were developed. These highlight settler tendencies, the current state of experiential education, recommendations for decolonization and an ideal future state, important approaches to consider when decolonizing as an individual and as a campus, cautions to heed, as well as values and emotions to consider. In order to decolonize experiential learning and the campus authentically, Indigenous voices must be and have been amplified in this process
Assessment of Water Resilience Principles in Water Policies and Plans: Niagara Region
Get PDFThe growing pressures on urban water services has created implications for managing and governing water sustainably affecting the resilience of social-ecological systems. Water governance resilience principles present an opportunity for water managers and policymakers to incorporate and respond to changes or disturbances within the water system. This case study investigates to what extent the resilience principles from the water governance literature are evident in water policies and plans at the regional municipality level in the Niagara Region. Through a content analysis of policy documents, it was found the presence of the seven
resilience principles differed across and within the documents with only one document containing all seven. These findings indicate that the policies and plans do not currently reflect sustainability principles which may have implications for the governance of water in the Niagara Region, and that further understanding of resilience principles is needed by governments and
policymakers in the region
Innovation Through Repurposing in Times of Crisis: An Exploratory Study
Get PDFThis research examines the concept of Innovation Through Repurposing (ITR), a strategic
alternative to traditional innovation from scratch, particularly in the face of crises. ITR, as defined for the
purpose of this study, involves the creative utilization of existing resources, often enhanced by
information technologies, to generate novel solutions. This study seeks to understand the factors that
contribute to a firm's decision to undertake ITR, drawing on current innovation literature and theoretical
precepts related to adaptability and resourcefulness.
We advance the notion of ITR, particularly under crisis conditions, where it may present a more
viable option for innovation due to heightened uncertainty, constrained timelines, and limited resources.
Recent examples indicate that firms may prefer or benefit from ITR during crises, underscoring the need
for a deeper understanding of this phenomenon.
This research is an exploratory study that further examines the conditions under which firms
might be motivated to undertake ITR. We propose that the urgency to innovate, coupled with the interplay
of information technology and organizational capabilities, plays a significant role in shaping the direction
and success of ITR.
Our methodology involves a mixed-method research design. Initially, we adopt a qualitative
approach involving individual interviews with executives and managers. Their experiences and insights
form a preliminary model for understanding crisis-driven innovation. Following this, we validate and
further probe these emergent ideas through focus group discussions. This approach allows us to cross verify findings and explore different perspectives, enhancing the richness and robustness of our
understanding. The findings from our qualitative study provided critical insights into how firms navigate
and pivot their strategies during crises by leveraging existing resources, confirming the potential and
importance of ITR in times of crisis. These results can form a substantive basis for further theorization
and quantitative empirical studies in the future.
Ultimately, this research aims to construct a well-structured nomological network of crisis-driven
innovation, offering actionable insights for organizations navigating future crises. By shedding light on
the dynamics of ITR, we aspire to enrich the literature on IS innovation and crisis management
Investigating the Effects of Perceptual Complexity versus Conceptual Meaning on the Neural Correlates of Visual Working Memory
Get PDFPrevious research has demonstrated greater visual working memory (VWM) performance for real-world objects compared to simple features. Greater amplitudes of the contralateral delay activity (CDA) have also been noted for meaningful stimuli, despite being thought of as a neural marker of a fixed working memory capacity. The current study aimed to elucidate the mechanisms underlying improved memory performance for real-world objects by isolating the relative contributions of perceptual complexity (number of features) and conceptual meaning (semantics). Participants (N = 22) performed a lateralized VWM task to test their memory of intact real-world objects, scrambled real-world objects and colours. The CDA was measured during perception and WM retention intervals (600-1000 ms and 1300-1700 ms post-stimulus onset, respectively), and behavioural performance was estimated as capacity (K; number of items correctly remembered in a two-alternative forced choice task). Behavioural performance was significantly greater within-subjects for intact objects relative to scrambled objects and colours, with no difference between colours and scrambled objects. The CDA amplitude was also largest for intact real-world objects, with no difference in magnitude for scrambled objects and colours, during WM maintenance. During perception, both the colours and intact real-world objects had significantly greater amplitudes than scrambled objects and were comparable in magnitude. Overall, findings suggest that conceptual meaning supports the object memory benefit. Comparisons of the CDA across stimulus type during encoding versus WM maintenance may also suggest that the waveform reflects more than purely the storage capacity of VWM
The Influence of Reward Associations in the Facilitation and Impairment of Attention and Conflict Processing
Get PDFThe ability to inhibit rewarding impulses to focus on goal-relevant information is a key feature of self-control and is implicated in many psychopathologies and maladaptive behaviours. Focusing on a feature such as the font colour of a word is impaired when the word meaning does not match the font colour (e.g., the word RED in a blue font colour), but even more so when the word meaning is associated with reward (i.e., a potential reward is available when the font colour of the word is red). This phenomenon is referred to as the modulation of interference by the reward association (MIRA) and is contrasted with the improvement of performance when the task-relevant font colour signals a potential reward (reward responsiveness). The present dissertation explores how reward influences Stroop performance, the psychometric properties of these influences, how individuals differ in the influence of reward on their attentional performance, and group-level experimental manipulations that modulate these effects.
In study 1, individual differences in behavioural measures of reward processing from the rewarded Stroop task (i.e., MIRA and reward responsiveness) and self-report measures of reward sensitivity and self-control were examined. While individual differences in reward responsiveness were reliable, individual differences in MIRA were not, suggesting that only reward responsiveness should be used to measure individual differences in behaviour. None of the self-report measures were related to behavioural measures suggesting that self-report and behavioural measures of similar constructs cannot be used interchangeably. Finally, there was no indication that reward responsiveness and MIRA were related In study 2, I used group-level manipulations to examine factors that could modulate reward responsiveness and MIRA. Whereas MIRA was relatively unaffected by these manipulations, reward responsiveness was increased for a large versus small reward, especially when colour-outcome instructions were provided. Further, individuals with high reward responsive tendencies responded faster to obtain a large reward but only when they were previously told which colour signals the large reward. Overall, these results highlight the dissociation between how reward can facilitate and impair attentional performance, and that further understanding this dissociation can have implications for our understanding of motivation and undesired reward-driven distraction
Exploring the COVID-19 Impact and Process of Value Change Towards Work and Leisure Among Millennials: "What Would I Rather Have: A Topped-Up RRSP or Stories of a Month Doing My Dive Master?"
Get PDFThe COVID-19 pandemic disrupted norms and routines such as employment status,
office space, and access to recreational services and programming. Values are defined as a broad
set of goals that influence behaviours, perceptions, and attitudes. Value change is thought to
occur in the wake of significant lifestyle disruption, such as marriage, parenthood, or the
COVID-19 pandemic. Research on value change is limited. Millennials (1981 – 1996) currently
make up 33.2% of the Canadian workforce. Therefore, significant change in values could hold
wider ramifications on the domains of work and leisure. This research asked two questions: (1)
In what way are Millennial males expressing their new values towards work and leisure? And (2)
What did the process of value change look like in young male Millennials? This research is
guided by a grounded theory approach, using intensive interview techniques to gather rich,
experience-driven data from seven young (1989 – 1996) millennial males living in Toronto,
Ontario, Canada. Data was analysed through an initial then axial coding process. A theory on the
process of change was determined through the coding process and revealed that participants
navigated through five stages: lifestyle disruption occurred to physical and psychological space.
Participants became aware of their dissatisfaction, through career choice, routines, and usage of
leisure time. Participants took action to address areas of dissatisfaction through career change
and implementing boundaries. Participants then proceeded with a maintenance period of
tinkering and increasing flexibility to seek the highest form of value-expressive behaviour.
Lastly, participants sought validation from self and from others.
Keywords: COVID-19, Work, Values, Millennials, Grounded Theor
Aligning Language Models Using Multi-Objective Deep Reinforcement Learning
Get PDFLarge Language Models (LLMs) have been a significant landmark of Artificial Intelligence (AI) advancement. Aligning LLMs to be helpful and harmless is a booming trend in Natural Language Processing (NLP). One of the dominant alignment techniques is reinforcement learning from human feedback (RLHF). RLHF aims to optimize one objective based on human preferences. However, the cost of high-quality human feedback is enormous. Having all human annotators consistent in their opinions on desirable behaviors is also challenging. LLM alignment is intrinsically a multi-objective optimization task since the goal is to train models to be helpful and harmless. It is found that helpfulness and harmlessness sometimes have problems in trade-offs, making it difficult for a model trained toward the optimization of one objective to perform well on both. Therefore, to address the highly potentially conflicting or dominating learning signal problem underlying LLM alignment, a multi-objective deep reinforcement learning (MODRL) methodology is proposed. The MODRL algorithm is based on an adapted deep reinforcement learning Advantage-Induced Policy Alignment (APA) algorithm and the Aligned-MTL approach for multi-task learning. From the overall perspective of helpfulness and harmlessness, language models trained via MODRL perform better than those trained using single-objective deep reinforcement learning methods that consider both objectives