Medicine and Health Sciences Commons^™

What Makes An Image Memorable? Effects Of Encoding On The Mechanism Of Recognition, Asiya Gul

Theses and Dissertations (Comprehensive)

Memory is undoubtedly one of the most important processes of human cognition. A long line of research suggests that recognition relies on the assessment of two explicit memory phenomena: familiarity and recollection. Researchers who support the Dual Process Signal Detection (DPSD) model of recognition memory link the FN400 component (a negative ERP deflection peaking around 400 ms at frontal electrodes) with familiarity; however, it is currently unclear whether the FN400 reflects familiarity or implicit memory. Three event-related potentials (ERP) studies were conducted to determine whether implicit memory plays a role in setting up encoding strategies, and how these encoding strategies …

Second Language Acquisition And Acculturation Differences Between Immigrants And Refugees, Ali Jasemi

Theses and Dissertations (Comprehensive)

The main difference between refugees and immigrants lies in the reason for their migration. Economic immigrants migrate to other countries voluntarily, while refugees are forced to leave their countries due to fear of death or persecution (UNHCR, 2018). Such fears may lead to psychological trauma among refugees. Research has shown that the presence of trauma can negatively impact language learning (Iversen, Sveaass, & Morken, 2014), which may have important implications for both second language (L2) acquisition and acculturation, particularly in refugees. In addition, strong linguistic abilities in a first language (L1) may be beneficial to acquire other languages (Cook, 2003). …

Processing Youth Adventure Wellness Experiences: Poetic Representations Of Youth’S Peace Bus Experiences, Ty Th Nguyen

Theses and Dissertations (Comprehensive)

This narrative inquiry explored how youth are processing their Peace Bus program experiences two and a half years after program completion. The purpose was to gain an understanding of (1) what program components the participants reflect on, (2) how they conceptualize their program experiences, and (3) what factors contribute to their reflection processes. This research sought to address the gap in literature where little is understood about the ongoing experiences of program participants of adventure wellness programs and the processes that lead to positive changes. As the researcher, I conducted a qualitative study using narrative inquiry and poetic representation methods. …

Auditory Erp Differences Across A Continuum Of Psychotic Symptoms In Non-Clinical Population, Anaya Rehman

Theses and Dissertations (Comprehensive)

Psychosis is a term given to a mental state described as a loss of contact with the real world. The aim of this thesis was to examine early non-specific psychotic experiences in a healthy population by means of two self-report screening tools: Prime Screen and Youth Psychosis At-Risk Questionnaire-Brief, and place individuals on a psychosis continuum. Across this psychosis continuum, three event related potential (ERP) components were assessed: P300, Mismatch Negativity and N100. There is evidence that P300 and mismatch negativity amplitudes diminish in individuals with psychosis. Similarly, impaired N100 amplitude suppression (increased N100 amplitudes) during vocalization has been observed …

Social Problems, Biomedical Answers? How Causes Of Social Problems Affect Choice Of Solutions, Bianca C. Dreyer

Theses and Dissertations (Comprehensive)

With rapid advances in behavioural genetics, scientists are identifying an increasing array of genetic influences on human behaviour. Public misconceptions about the function of genes often lead to the oversimplification of the role of genes in behaviour (Dar-Nimrod & Heine, 2011). To date, no study has systematically investigated whether simply learning about genetic causes of behaviour affects people’s preferred solutions to problematic behaviours. The present research program includes three studies that were designed to examine the psychological effects of exposure to genetic etiology for problematic behaviour, in particular aggression, and investigated how this information influences endorsement of solutions, rating of …

The Effects Of External Focus Of Attention Exercise Rehabilitation On Dual Task Walking In Parkinson's Disease, Eric N. Beck

Theses and Dissertations (Comprehensive)

Parkinson’s disease impairs control of well-learned movements, and therefore, individuals with Parkinson’s disease are forced to walk with greater conscious control. This causes difficulties while walking and completing a secondary task simultaneously (dual tasking), in that distractions from conscious control of walking increase the risk of falls and injury. Although, attention-based exercise may be a potential avenue to decrease the demands associated with walking in Parkinson’s disease. For example, an external focus of attention (on manipulated objects) has been found to recruit the networks that are important for walking with little conscious control (automatic control networks). In contrast, an internal …

The Role Of Taste And Calories In Access-Induced Excessive Sweets Consumption By The Rat, Adam Celejewski

Theses and Dissertations (Comprehensive)

For individuals diagnosed with Binge Eating Disorder (BED) or Bulimia Nervosa (BN) eating is often manifested in intermittent bouts of gorging, a behaviour that is similar to excessive consumption of rewarding drugs in addiction (American Psychiatric Association, 2000; Corwin & Grigson, 2009; Epstein & Shaham, 2010). Our laboratory has found that sucrose solution intake by rats escalates markedly when provided on Discontinuous Access (DisA; 24h once every 3 or 4 days) schedules but is maintained at lower, stable levels with Continuous Access (ConA; ad lib) schedules (Hewitt & Eikelboom, 2008). Once DisA/ConA consumption differences are established, they persist even …

Effects Of Chlorpromazine On Feeding And Wheel Running On Rats With Acute Wheel Access, Graham Gregory Parfeniuk

Theses and Dissertations (Comprehensive)

Anorexia Nervosa (AN) is characterized by a self-imposed starvation and is often accompanied by excessive exercise that results in severe malnutrition and sometimes death. Behavioural and pharmacological treatments of AN need to be improved. In rats, acute 3 h daytime wheel access suppresses ad lib feeding over the subsequent night relative to no wheel controls, a phenomenon that has been suggested as an animal model of AN. This acute wheel induced feeding suppression (WIFS), can be induced reliably when rats are given limited wheel access exposure during the light cycle (Lattanzio & Eikelboom, 2003). The acute WIFS is useful because …

Neural And Behavioral Responses To The Use Of Auditory Feedback In Vocal Control, Colin S. Haweo

Theses and Dissertations (Comprehensive)

A large body of evidence suggests that the motor system maintains a forward model that predicts the sensory outcome of movements. When sensory feedback does not match the predicted consequences, a compensatory response corrects for the motor error and the forward model is updated to prevent future errors. Like other motor behaviours, vocalization relies on sensory feedback for the maintenance of forward models and to stabilize vocalizations.

Experiment 1 used event-related potentials (ERPs) to examine sensory processing of short feedback perturbations during an ongoing utterance. In one session, participants produced a vowel at an FO of their own choosing. In …

Effects Of Context On Target Localization, Cheryl M. Lavell

Theses and Dissertations (Comprehensive)

The purpose of this thesis was to investigate how the presence of non-target objects can influence the planning of a movement towards a remembered target location. One specific aim was to examine how the temporal effects of the task could affect movement planning. The final aim of this thesis was to examine whether or not the mere presence of extrinsic cues can suppress the encoding of intrinsic cues.

It was found that when non-target objects are presented simultaneously with the target, interference occurs; however, if the non-target objects are presented at least 250 ms in advance of the targets performance …

Birds Of A Feather Sit Together: Physical Similarity Predicts Seating Choice, Sean Mackinnon

Theses and Dissertations (Comprehensive)

The relationship between physical similarity and seating preference was examined using two observational studies and one laboratory study. Using Campbell et al.’s (1966) seating adjacency formula, Study 1 found significant aggregation by glasses-wearing status and sex when observing seating patterns in a library computer lab. That is, men sat beside other men, glasses-wearers by other glasses wearers, and so on. Study 2 broadened this methodology by examining a wider variety of physical traits in university classrooms; specifically, race, sex, glasses-wearing, hair length and hair colour. Broadly speaking, multivariate tests revealed an overall tendency for people to sit beside physically similar …

The Effect On Response Complexity On Task-Switching Behaviour, Christina Shepherd

Theses and Dissertations (Comprehensive)

Research on task-switching has shown that when participants are asked to switch between two different tasks, they are slower than when they repeat the same task. These costs have also been shown to increase when the previous response is repeated; however, very little has been done to investigate the role of response complexity in this relationship. We manipulated response complexity by increasing both the number of stimulus-response pairs and the number of individual response components. We hypothesized that increased response complexity would increase both the switch costs and the response repetition effect. Results indicated that increasing the number of S-R …

The Tactile Motion Aftereffect, Peggy Joanne Planetta

Theses and Dissertations (Comprehensive)

The tactile motion aftereffect (tMAE) is a perceptual phenomenon in which illusory motion is reported following adaptation to a unidirectionally moving tactile stimulus. Unlike its visual counterpart, relatively little is known about the tMAE. For that reason, the purpose of this dissertation was to gain a better understanding of the tMAE using both psychophysical and neuroimaging techniques. In a series of five experiments the skin was adapted using a plastic cylinder with a square-wave patterned surface. Chapter 2 consists of two experiments, both of which adapted the glabrous surface of the right hand. Experiment 1 showed that the prevalence, duration, …

Can Overeating Induce A Conditioned Taste Avoidance In Previously Restricted Rats?, Amanda Louise Hertel

Theses and Dissertations (Comprehensive)

While feeding is rewarding, the feeling of satiation has been theorized to be aversive under certain conditions. Using a food-restriction model of overeating developed in our laboratory the results presented here suggest that overeating, and the resulting experience of satiation, is capable of supporting a conditioned taste avoidance.

Rats had either ad lib (n=8) or restricted (n=24) food access (receiving 50% of the food eaten by ad lib fed rats) for 8 days. All rats were then given 24 hr access to a 0.1% saccharin solution, and two groups of food-restricted rats were given access to either 100% of the …

Internal And External Triggers For Action, Shannon Matkovich

Theses and Dissertations (Comprehensive)

When the self paced preparation of an action is interrupted by a stimulus prompting the same motor response there is an increase in the reaction time to the stimulus as compared to an external or simple reaction time (SRT) condition (Obhi & Haggard, 2004). Previous studies have suggested that this cost is not attributable to perceptual or attentional factors. Therefore, to investigate the source of this RT cost we varied the motor demands of movements in Experiments one and two. Results indicated that the level of motor programming demands did not influence the RT cost in these experiments. While RTs …

Neural And Behavioural Effects Of The Ginkgo Biloba Leaf Extract Egb 761, Elham Satvat

Theses and Dissertations (Comprehensive)

Numerous studies have documented the cognitive-enhancing effects of standardized Ginkgo biloba leaf extracts (Ginkgo) both in humans and in rodents. In addition to its antioxidant and platelet-activating factor inhibiting properties, Gingko has been shown to protect cellular membrane fluidity, to enhance cerebral blood flow and microcirculation, and to modulate cholinergic system functioning, properties that have been suggested to underlie its cognitive-enhancing effects. However, the possible neurogenic-enhancing effects of Ginkgo on adult hippocampal neurogenesis as a possible mechanism underlying its nootropic effects have not been evaluated. The experiments discussed in the present thesis assessed such a possibility.

Chapter 1 …

Escalation Of Wheel Running: An Animal Model Of Non-Drug Addiction, Ali Gheidi

Theses and Dissertations (Comprehensive)

Animal studies using the self-administration paradigm suggest that duration of drug access (Ahmed, 2005) and individual phenotype (Piazza, Deminiere, Le Moal and Simon, 1989) are important factors in the development of drug addiction. Wheel running in rats has been proposed as a model to study non-drug addictions (Eikelboom & Lattanzio, 2003). When first given ad lib wheel access, young male rats initially run at low levels (about 1000 wheel turns per night) and gradually increase this distance to high levels (about 5000 wheel turns per night) (Afonso and Eikelboom, 2003). Like with self-administration, duration of wheel access has been found …

List Composition Effects For Masked Semantic Primes: Evidence Inconsistent With Activation Accounts, Jennifer C. Major

Theses and Dissertations (Comprehensive)

Priming is the benefit that an event receives when its processing has been preceded by the processing of a related or identical event. Context effects on priming are evident when priming changes as a function of some feature of experimental trials. The most commonly explored context effect is that of relatedness proportion (RP), where it has often been shown that the magnitude of priming (semantic or repetition) is directly related to the proportion of related trials: Increasing the related trials results in greater priming. Although previously thought to depend on strategic processing, recent evidence of context effects from designs using …

The Effects Of Food Restriction On Wheel Running In Rats, Vanessa M. Lopak

Theses and Dissertations (Comprehensive)

The impact of food restriction and refeeding on wheel running was examined in 3 groups of rats: 55 day old male rats in Experiment 1; 140 day old male rats in Experiment 2; and 180 day old female rats in Experiment 3. After a baseline period of 24 to 40 days wheel experience with ad lib food access half of the animals were food restricted for 16 days by being given a limited amount of food daily to reduce (and maintain) their body weight at 85% of their baseline weight. After food restriction the rats were returned to ad lib …

Transition From Moderate To Excessive Wheel Running In Rats: A Function Of Access Length?, Sara B. Lattanzio

Theses and Dissertations (Comprehensive)

In rats, long daily wheel access produces an escalation to excessive levels of running while short daily access results in low stable levels of running. paralleling patterns of cocaine- taking (Lattanzio et al., 2000). Experiment I explored the effects of previous running experience (Phase l) on fixture running and feeding (Phase ll). Rats with 24 h daily access in Phase I escalated wheel running to a plateau of about 7000 wheel turns per day, while rats with 2 h daily access ran at low levels (about I000 wheel turns over the final 8 days of Phase l). The 2 h …

The Effect On Feeding And Wheel Running Behaviours Of Housing Rats In Pairs, Roison M. O'Connor

Theses and Dissertations (Comprehensive)

The effects on feeding of moving animals from individual- to pair-housing were explored in the present three experiments. Wheel access is known to result in a temporary suppression of feeding. The move to pair-housing was compared with the effect of wheel access. In Experiment l, a group of rats was moved from individual to pair-housing (IP group) and compared to a group of individually-housed rats (IND group) and a group of chronically pair-housed rats (PAIR group). The animals in the IP group showed a temporary (three days) suppression in feeding (initially 23%). When half of the IND and PAIR group …

Responsible Environmental Behaviour: A Test Of The Hines Model, Karen Hayward

Theses and Dissertations (Comprehensive)

As the number and salience of environmental problems have increased so have the number of studies which investigate environmentally responsible behaviour. Hines (1984), after conducting a meta-analysis of this literature, identified crucial variables which predict responsible environmental behaviour. While Hines has proposed a crude model which contains the variables thought to explain this type of behaviour, she has failed to hypothesize about the relationships that exist amongst many of these variables. The present study, therefore, was designed to develop a more elaborate model which attempts to explain some of these relationships, as well as predict responsible environmental behaviour. The sample …

Stress, Social Support And Parental Behavior, Mila M. Buset

Theses and Dissertations (Comprehensive)

The present study investigated the relationship between stress, social support and parenting behavior. Eighty-six mothers who had a child enrolled in a daycare center in the Kitchener-Waterloo region volunteered for this study. Participants completed four questionnaires: A Demographic Sheet, the Perceived Stress Scale (Cohen, Kamarck & Mermelstein, 1983), the Interpersonal Support Evaluation List (Cohen and Hoberman, 1983), and the Parent Behavior Scale (which was specifically constructed for this study). The overall support scale and the four subscales (tangible, belonging, appraisal, and self-esteem support) were used to determine whether the perceived availability of social support is directly related to parenting behavior …

An Evaluation Of Drama Therapy As A Form Of Secondary Prevention For Children With Social Skills Deficits, Myra Kosidoy

Theses and Dissertations (Comprehensive)

The following study investigated the effectiveness of an intervention that was based on creative drama designed to improve the social skills of school age children identified as deficient in social-emotional development. The intervention, termed the structured fantasy approach, combines theoretical principals from psychodynamic theory, social learning theory, and creative drama. The study was conducted at a public school in the Kitchener-Waterloo area. Eight students from the third to sixth grade participated in a ten-week social skills program, while seven students from first to third grade participated in a similar program. Five first to third graders and four third to six …

Assessing Socially Skilled Behaviour For Vocational Tenure In Adults With Developmental Disability, Paula M. Daoust

Theses and Dissertations (Comprehensive)

Socially skilled behaviour is a critical factor in an individual's ability to secure and maintain employment. Due to the very nature of their handicap, persons with mental retardation often exhibit social skills deficits, thus restricting access to competitive employment and the status of full membership in society that such employment facilitates. Previous attempts to train socially skilled behaviour in persons with mental retardation have been hampered by the lack of a valid assessment tool to evaluate program effectiveness and inform program content. The purpose of this paper was to develop such an instrument by extending work done by Lagreca, Stone …

Drawing With And Without Models: An Examination Of Drawing Behavior In Children And Adults, Jenet Bogles

Theses and Dissertations (Comprehensive)

Research in drawing development has indicated that individuals’ drawing behavior changes with age. Preschoolers, six, nine, twelve year-olds, and adults participated in the present study since these ages corresponded to the most prominent stages noted in the literature. Part one of this study examined drawing behavior in three drawing conditions: a model-absent condition (C1) in which drawing took place following a brief verbal description, a model briefly-present condition (C2) in which the model on which the verbal description was based was examined and drawn when removed from sight, and a model continuously present-condition (C3) in which drawings were made while …

The Impact Of Evaluation Feedback On Affective And Behavioural Reactions, Kathleen Joy Kitching

Theses and Dissertations (Comprehensive)

A study was conducted to examine the impact of outcome (success or failure) and attribution information cues (none, internal, external) on affective and behavioural reactions to performance feedback. Following the theorizing of Weiner, Russell, and Lerman (1978, 1979) and Liden and Mitchell (1985), it was predicted that the outcome manipulation would determine a global affective reaction and that the attribution information cues manipulation would polarize these reactions. Sixty university undergraduate students were randomly assigned to success of failure on a practice and final creativity test and were induced to attribute their performance to internal or external causes depending on attribution …

The Relative Contributions Of State And Trait Empathy In The Motivation Of Helping Behaviour, David Scott Melford Pawson

Theses and Dissertations (Comprehensive)

This research examined the relative contributions of situational (state) and dispositional (trait) empathy in the motivation of helping behaviour. Forty W.L.U. undergraduates who volunteered from an original sample of 193 participated in a study in which state and trait empathy were crossed in a 2 X 2 between-subjects design. State empathy was manipulated by perspective taking instructions and trait empathy via a median split of the participants’ Questionnaire Measure of Emotional Empathy scores (filled out previously). Under the guise of an emotional reaction study they were asked to help another student by promising to participate in further research. Both this …

Towards The Development Of A Resource Center For Individuals With Anorexia Nervosa And/Or Bulimia A Needs/Resource Assessment, Professional Networking, And Program Planning Process, Tammy Lee Morrell

Theses and Dissertations (Comprehensive)

An assessment of service needs and resource availability for clients with the eating disorders anorexia nervosa and bulimia was conducted in the Waterloo region, located in southwestern Ontario, in order to ascertain the number of individuals in the region who currently suffer from the disorders but for various reasons have not sought treatment. In addition, the assessment examined the availability of specialized services for this client population, the sufficiency of extant services in relation to estimated service needs, and the degree of inter-agency networking in treating eating disorders. A variety of needs/resource assessment techniques were utilized including the social indicators …

The Anti-Electroconvulsive Therapy Movement In Ontario A Description And Analysis, Karen T. Hooper

Theses and Dissertations (Comprehensive)

Recently, a movement emerged in Ontario which attempted to ban the use of electroconvulsive therapy (ECT), a controversial psychiatric treatment. The purpose of this study was to describe and analyze the anti-ECT movement as a contemporary social movement. The research foci of this study pertained to: 1) the movement’s goals and organizational structure, 2) its resource mobilization efforts, and 3) the political environment in which it evolved. Three sources of data were used: key informant interviews, newspaper archives, and OHIP data depicting aggregate numbers of ECT use in Ontario. The anti-ECT movement developed from the activities of self-help groups within …