Behavior and Behavior Mechanisms Commons^™

Cerebral Hyperemia Is Not A Sole Modulator Of Postexercise Executive Function Benefit: Evidence From Hypercapnia And Passive Exercise, Mustafa Shirzad

Electronic Thesis and Dissertation Repository

A single bout of exercise improves executive function (EF); however, the physiological mechanism(s) contributing to this benefit are unclear. One candidate mechanism for the benefit is an exercised-mediated increase in cerebral blood flow (CBF) that improves neural efficiency. In my thesis, I conducted two experiments to assess the relationship between an increase in CBF and EF. In Experiment 1, I examined passive exercise, and in Experiment 2, I examined a 2.5% hypercapnic environment given that both interventions increase CBF independent of the metabolic demands of volitional muscle activity. Experiment 1 indicated that passive exercise increased CBF and was associated with …

The Effect Of Propionic Acid On The Habituation To Social And Non-Social Odour Cues In Adult Male Rats, Cashmeira-Dove P. Tyson

Electronic Thesis and Dissertation Repository

The enteric bacterial metabolite, propionic acid (PPA), elicits physiological and behavioural changes in rodents reminiscent of autism spectrum disorder (ASD). This includes abnormal sensory processing and social behaviour. ASD may contribute to social deficits through impaired habituation; therefore, the present study examined the effects of intraperitoneal PPA on the habituation to social and non-social odours. Adult male rats were injected daily with PPA or the vehicle control, and for 3 days, habituated to a conspecific odour or vanilla extract for 10 minutes. On day 4, rats were exposed to a novel conspecific odour or almond extract for 10 minutes to …

The Effects Of The Aromatase Inhibitor, Letrozole, On Lithium Chloride (Licl)-Induced Conditioned Disgust Behaviour (Anticipatory Nausea) In Male Rats, Vangel Matic

Undergraduate Student Research Internships Conference

Anticipatory Nausea (AN) is a form of classical conditioning in which the effects of a nausea-inducing toxin become associated with a specific environmental context. AN is often experienced by individuals receiving chemotherapy treatment, whereby the emetic effects of the chemotherapy agents become associated with the treatment context (i.e. hospital, clinic), such that exposure to the context alone can cause an individual to experience nausea and potentially withdraw from treatment. Chemotherapy-associated AN is suggested to have a higher incidence in females compared to males.

AN can be represented in a rodent model (conditioned disgust) through the occurrence of conditioned gaping behaviour …

Investigating The Role Of Targeted Memory Reactivation In Sleep Spindle Production, Justin W. Hopper

Electronic Thesis and Dissertation Repository

In ‘targeted memory reactivation’ (TMR) paradigms, information learned during wakefulness is paired with a cue, and reactivated during sleep by presenting that same cue. TMR improves memory. In a prior study (Antony et al., 2012), participants learned two melodies. One melody was cued during a nap, and performance was better than for the uncued melody. The current study reanalyzed these data to characterize sleep spindle density during TMR cue-periods relative to non-cued periods, and whether spindle density correlated with performance. During TMR stimulation, spindle density was significantly higher than during non-stimulation in four time windows. Compared to the non-TMR group, …

Why Do People Engage In Eating Disorder Behaviours?, Abbigail Kinnear

Electronic Thesis and Dissertation Repository

Eating disorders (EDs) are serious mental illnesses often with poor prognosis. Personalizing evidence-based treatments based on an individual’s reasons for engaging in ED behaviours – or the functions of EDs – may improve treatment outcomes; however, no validated measures assessing these functions exist. The goal of this study was to complete the initial steps in developing a measure of ED functions. Individuals who engage in ED behaviours (n = 16) and clinicians who treat EDs (n = 14) were interviewed, and a thematic analysis was conducted to determine key functions of EDs. Four main functions of EDs were …

The Impact Of Levodopa Administration On Learning From Short-Term And Long-Term Action Consequences: A Paradigm Validation., Masood Rezaei

Electronic Thesis and Dissertation Repository

Behavioral and neuroimaging studies have identified two valuation systems in the human brain for controlling behavior known as model-free (MF) and model-based (MB). MF is based on immediate evaluation and MB is based on long-term evaluation of the outcome of our decisions. Previous studies suggest that dopamine baseline activity may play an important role in the balance between the two systems and determine how they compete or interact in controlling our actions. The overarching aims of this study is to investigate the impact of levodopa administration on learning from immediate and long-term action consequences, and to dissociate the role of …

Using Meditation To Improve Measures Of Attention In Older Adults, Sabrina Ford

Electronic Thesis and Dissertation Repository

Age-related cognitive decline greatly impacts quality of life for older adults. Previous research has indicated that meditation may act as a neuroprotective factor to prevent age-related cognitive decline. This thesis sought to replicate previous findings and investigate if a four-week meditation intervention would improve sustained attention. Participants 60 years and older (n=27, 17 female) were recruited and assigned to a focused-attention (FA) meditation or relaxation group which met for four weeks, three times a week. Resting-state EEG was used to collect individual alpha peak frequency (iAPF) and frontal alpha asymmetry (FAA). The Sustained Attention to Response Task (SART) was also …

Mouse Performance On A Novel Touchscreen Continuous Performance Task Is Dependent On Signaling In The Prelimbic Cortex, Tyler D. Dexter, Daniel Palmer, Amy C. Reichelt, Anita Taksokhan, Lisa M. Saksida, Tim J. Bussey

Western Research Forum

Attention is the cognitive processing that facilitates the ability to target and attend to relevant environmental stimuli, while filtering out irrelevant or distracting stimuli. Control over selective attention is theorized to be dependent on organized neural communication that stems from the medial prefrontal cortex (mPFC). To evaluate selective and sustained attention, mice were trained on the novel touchscreen rodent continuous performance task (rCPT), a task designed to emulate the human CPT. In the rodent version, images are continuously presented on a touchscreen, where mice have been trained to selectively respond to one image type while suppressing responses to all others. …

The Effect Of The Dopamine Agonist Pramipexole On Measures Of Impulsivity In Young, Healthy Participants, Daniel Glizer

Electronic Thesis and Dissertation Repository

Patients with Parkinson disease are prescribed dopamine agonists such as pramipexole to improve motor symptoms. Several studies have found that patients taking dopaminergic medication develop impulse control disorders. In contrast, other studies suggest that some behaviors become less impulsive with pramipexole. We evaluated the performance of 20 young, healthy participants who received pramipexole (0.5 mg) and 20 participants who received placebo, on the Go/No-Go, the Stop Signal Task, and the Balloon Analogue Risk Task. We found that the pramipexole group had more timed out Go trials on the Go/No-Go task than the placebo group, suggesting reduced motor impulsivity. There were …

Smoking And Exercise: Mechanisms And Effects During Simulated And Genuine Quit Attempts, Stefanie De Jesus

Electronic Thesis and Dissertation Repository

Cigarette smoking is a leading agent for premature morbidity and mortality among the global community. Most individuals surrender to tobacco use disorder due to the inability to cope with cravings and withdrawal symptoms. Exercise appears to provide acute relief. Currently, it is unclear how exercise attenuates these reductions. Furthermore, the available evidence has focused on acute outcomes besides smoking behaviour and is limited to simulated quit attempts. Three experimental studies were designed to address these outstanding issues. Not surprisingly, a bout of moderate intensity exercise was found in study 1 (chapter 2) to reduce cravings associated with a temporary period …

Does Satisfaction With Perinatal Health Care Influence Postpartum Weight Retention?, Andreea Bente

Electronic Thesis and Dissertation Repository

The primary aim of this thesis is to identify whether satisfaction with perinatal health care encounters is associated with lower postpartum weight retention (PPWR). PPWR is the difference between postpartum and pre-pregnancy weight. Principal components analysis confirmed the validity of a summed satisfaction score representing six dimensions: information, compassion, competency, privacy, respect and decision-making. Confounders were identified using a directed acyclic graph. Multivariable linear regression models were constructed using blocks, and backwards elimination. Results reflect a mean PPWR of 2.5 kg, and high satisfaction, with more than 90% of respondents being very satisfied or satisfied on each dimension. The multivariable …

Seeing With Sound: Investigating The Behavioural Applications And Neural Correlates Of Human Echolocation, Jennifer L. Milne

Electronic Thesis and Dissertation Repository

Some blind humans use the reflected echoes from self-produced signals to perceive their silent surroundings. Although the use of echolocation is well documented in animals such as bats and dolphins, comparatively little is known about human echolocation. The overarching goal of the work presented in this thesis was to shed light on some of the basic functions of human echolocation, including the perception of the shape, size, and material. I addressed these aspects of echolocation using behavioural psychophysics and neuroimaging.

In Chapter 2 I show that blind echolocators were able to accurately identify the shape of 2D objects, but that …

Exploring The Neural Basis Of Top-Down Guided Action In Macaque Monkeys, Jessica M. Phillips

Electronic Thesis and Dissertation Repository

To thoroughly characterize any brain mechanism requires an appropriate animal model for invasive studies. An invaluable model system used toward a comprehension of cognitive neurophysiology is the macaque monkey. It is important to delineate similarities and limitations for this model in relation to the human brain and cognition. In this thesis, we have thus conducted three experiments to investigate putative generalizations between monkeys and humans regarding the neural processes associated with top-down action control in monkeys.

Our daily behaviour is largely comprised of automatic routine actions. The frequent repetition of certain behaviours in response to particular contexts can give rise …

The Importance Of Self-Efficacy And Basic Psychological Needs In Children’S Physical Activity: Measurement, Prediction And Intervention, Casey E. Gray

Electronic Thesis and Dissertation Repository

The importance of physical activity in the overall health promotion and primary prevention of cardiovascular disease risk factors and metabolic diseases in children is well established. Nonetheless, interventions to increase physical activity among this population have been largely unsuccessful. The main objective of the research in this dissertation was to explore the suitability of self-efficacy and basic psychological needs for physical activity prediction and intervention in children. Item generation and psychometric evaluation of psychological questionnaires occurred in study 1 (Chapter 2). Using a prospective design, study 2 (Chapter 3) established task efficacy, barriers efficacy, competence, and autonomy as significant predictors …