Psychology - Theses, Dissertations, and other Required Graduate Degree Essays

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Truth and Deception in Informants' Accounts of Criminal Admissions

Date created: 
2017-07-13
Abstract: 

Informants who report admissions to crime can be powerful and dangerous players in the criminal justice system. Some informants, such as jailhouse informants, are considered deceitful, in part because they can receive incentives to report criminal admissions. However, little research has examined the nature of information that informants provide. In particular, no recent published research has examined whether there are valid behavioural cues that distinguish deceptive from truthful informants. In addition, no published study to date has explored whether informants’ reports and demeanours are affected by the incentives that they receive. Participants in this study either did or did not hear a criminal admission and then were interviewed one week later about details of the admission they had allegedly heard. Some participants were offered an incentive to report the criminal admission in a way that appeared accurate and forthcoming. The results of this study suggest that there may be behavioural cues emitted during the reporting of criminal admissions that distinguish truthful from deceptive informants. However, the direction of differences for some cues may deviate from other types of witnesses to crime. In addition, the findings of this study indicate that being offered an incentive may induce informants to emit cues during the reporting of criminal admissions that make them appear more truthful, regardless of whether or not they are actually telling the truth. The findings of this study raise concerns about whether informants’ honesty should be assessed in the same way as other witnesses, and about potentially negative consequences of offering incentives to informants in exchange for their reports of criminal admissions.

Document type: 
Thesis
File(s): 
Senior supervisor: 
J. Don Read
Department: 
Arts & Social Sciences: Department of Psychology
Thesis type: 
(Dissertation) Ph.D.

Structured Professional Assessment and Management of Self-Directed Violence (SDV): The SDV-20

Date created: 
2017-07-20
Abstract: 

Suicidal behaviour has been documented in almost every country and was the second leading cause of death in 2012 among persons aged 15 to 29 (World Health Organization, 2014). Each year, up to one million people die by suicide worldwide. Suicide is a global challenge for medical and mental health organizations, and presents a significant systemic burden if not managed effectively (Knox & Caine, 2005). Currently, there appears to be an over-reliance on the use of “checklist” methods for assessing suicide risk (e.g., SAD PERSONS; Patterson, Dohn, Bird, & Patterson, 1983), and a great need for empirically guided risk assessment approaches that utilize the advantages of clinical or professional judgment, rather than relying solely on the outcome of quantitative or checklist measures (Range, 2005). Strict quantitative or statistical approaches often do not adequately capture the range of dispositional and contextual factors influencing risk for particular behaviours (Hart, 2008; Hart & Cooke, 2013). Thus, the purpose of the current project will be to conduct a systematic and selected review of the literature and develop a set of structured professional judgment guidelines for assessing suicide risk.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Alexander L. Chapman
Department: 
Arts & Social Sciences: Department of Psychology
Thesis type: 
(Dissertation) Ph.D.

Is pop-out search impaired during the period of the attentional blink?

Date created: 
2017-06-22
Abstract: 

The involvement of attention in pop-out visual search is controversial. According to some theories, efficient pop-out search is accomplished preattentively, while others claim the involvement of attention is essential. In the present work, the role of attention in performing pop-out search tasks was elucidated by manipulating the availability of attention using an attentional blink (AB) paradigm. In Chapter 2, the efficiency of pop-out search – indexed by the slope of response time (RT) functions over the number of items in the search array – was examined throughout the period of the AB. Search efficiency was found to be unaffected by the AB, although the overall level of RT was slower during the AB. These findings suggest the action of at least two separable mechanisms underlying performance in pop-out search tasks, indexed by level and efficiency of search, which are affected in different ways by the availability of attention. In Chapter 3, the role of selective attention in pop-out search was examined by measuring the onset latency of the N2pc, an event-related potential index of attentional selection. Both the RT and the N2pc measures were delayed during the AB, but the delay in N2pc was substantially shorter than that in RT. This pattern of results points to multiple sources of delay in the chain of processing events, as distinct from the single source postulated in current theories of the AB, and strongly suggests that selective attention is involved in pop-out search tasks. In Chapter 4, the relative exogenous and endogenous salience of two targets (T2, T3) presented throughout the period of the AB were manipulated in order to assess whether the perception of salience is impaired during the AB. The perception of temporal order of these targets was measured. Both exogenous and endogenous salience were found to be effective in modulating the perception of temporal order throughout the period of the AB, suggesting that the effect of salience is broadly additive with the overall AB effect. In Chapter 5, the implications of these findings for both search and the AB, are discussed and future research directions are proposed.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Thomas Spalek
Department: 
Arts & Social Sciences: Department of Psychology
Thesis type: 
(Dissertation) Ph.D.

Love hurts: Predicting trajectories of marital satisfaction from couples’ behaviour during discussions of interpersonal injuries

Author: 
Date created: 
2017-07-13
Abstract: 

Interpersonal injuries are inevitable in intimate relationships (cf. Fincham, 2000) and addressing the emotional fallout from these experiences is challenging. Although interpersonal injuries have important consequences for relationships (Lemay et al., 2012), little is known about the dyadic process that facilitates the resolution of hurt feelings and helps couples to maintain or to strengthen relationship well-being. I examined whether couples’ observed behaviour during discussions of interpersonal injuries predicted trajectories of marital satisfaction over two years. Multilevel modelling indicated that marital satisfaction declined over two years, and wives’ positive behaviour during discussions of husbands’ hurt feelings buffered declines in wives’ satisfaction. Specifically, wives who were more emotionally positive had increases in marital satisfaction, whereas wives who were less emotionally positive had decreases in marital satisfaction. Husbands’ and wives’ negative behaviour during discussions of husbands’ hurt feelings hastened declines in marital satisfaction for both spouses. Couples’ behaviour during discussions of wives’ hurt feelings did not moderate trajectories of marital satisfaction, with one exception. Husbands who asked more questions during the discussion of wives’ hurt feelings had increases in marital satisfaction, whereas husbands who asked fewer questions had decreases in marital satisfaction over time. Couples’ ability to navigate discussions of hurt feelings following interpersonal injury may be critical for repairing and maintaining relationship well-being.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Rebecca Cobb
Department: 
Arts & Social Sciences: Department of Psychology
Thesis type: 
(Dissertation) Ph.D.

Searching “Inaffectively”: A Behavioral, Psychometric, and Electroencephalographic Investigation of Psychopathic Personality and Visual-Spatial Attention

Date created: 
2017-06-23
Abstract: 

Psychopathic personality’s characterization by abnormal visual-spatial attention and emotional response during visual search was evaluated in 3 related empirical investigations. Study 1 examined whether psychopathy impacts event-related potential (ERP) measures of stimulus salience (Ppc), target selection (N2pc), distractor suppression (Pd), and working memory (CDA). Psychopathic impulsivity traits were positively correlated with heightened visual-cortex salience calculations for distractor stimuli, requiring subsequent spatial suppression of those items. However, psychopathy was unassociated with target selection ability. Study 2 assessed whether psychopathy alters ERP measures of emotional face target salience (Ppc), selection (N2pc), and working memory representation (CDA). Similar to the results observed with low-level feature targets in study 1, even when targets were defined by complex emotional categories psychopathy remained unassociated with selection. Instead, the condition was negatively correlated with the strength of emotional face representations in working memory. Finally, study 3 tested whether individual differences in psychopathy explain longstanding discrepancies in a behavioral measure of efficiency during search for emotional faces (search slope). Detection of emotional targets was inefficient for all participants, and this effect was not moderated by the presence of psychopathic traits. These results clarify several mechanisms underlying the attention and affect irregularities proposed in theoretical models of psychopathic personality. Rather than failure to detect information outside immediate focus, study 1 suggests external stimuli are hyper salient during pre-attentive scans, but are reflexively hyper suppressed. Studies 2 and 3 demonstrate emotional expression detection is unimpaired, but affective abnormalities occur later during evaluation. Notably, across all participants the emotional status of stimuli was best reflected at evaluative stages, not spatial reorienting stages. This is in line with guided search attention models, which posit that only select low-level stimulus features have the capacity to direct visual-spatial focus, and psychological construction affect models, which argue that perception of discrete emotional states occurs during conceptual evaluation of ostensibly emotional objects.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Mario Liotti
Department: 
Arts & Social Sciences: Department of Psychology
Thesis type: 
(Dissertation) Ph.D.

Giving leads to happiness in at-risk and antisocial populations

Date created: 
2017-06-07
Abstract: 

Research suggests that the emotional benefits of prosocial behaviour may be universal; adults and children from various countries around the world experience happiness from engaging in prosocial action. Importantly, psychological universals may not only be detectable in diverse contexts, but across a range of actors as well – including individuals with antisocial tendencies. Three studies examined whether individuals with criminal histories and antisocial inclinations experience hedonic rewards from engaging in prosocial behaviour. In Experiment 1, high-risk youth and juvenile offenders (N = 64) who were randomly assigned to purchase candy for a children’s charity reported greater positive affect than those who purchased candy for themselves. In Experiment 2, adult ex-offenders (N = 501) randomly assigned to recall and describe the last time they spent money on someone else reported higher positive affect controlling for baseline levels of well being than those who recalled spending on themselves. In Experiment 3, adult ex-offenders (N = 777) randomly assigned to donate funds to a charity organization reported higher positive affect than those who used the funds to purchase an item for themselves. Self-reported antisocial tendencies did not moderate the emotional rewards of prosocial spending in any study. These findings suggest that the hedonic rewards of prosocial behaviour are detectable in high-risk and ex-criminal populations, providing further support for the universal benefits of generosity.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Lara Aknin
Department: 
Arts & Social Sciences: Department of Psychology
Thesis type: 
(Thesis) M.A.

Emotion differentiation, borderline personality features, and self-destructive behaviour

Date created: 
2017-07-20
Abstract: 

I examined the association of negative emotion differentiation with borderline personality (BP) features, and whether negative emotion differentiation moderates the association of BP features with self-destructive behaviour. Undergraduate and community participants first completed questionnaires assessing BP features and psychopathology. Subsequently, ecological momentary assessment and daily diary methods were used to assess emotion, urges to engage in self-destructive behaviour, and self-destructive behaviour engaged in over a 14-day period. As a measure of negative emotion differentiation, intraclass correlation coefficients were calculated from the repeated administration of the emotion questionnaire. As predicted, BP features were negatively associated with negative emotion differentiation. As well, multilevel modelling revealed that negative emotion differentiation moderated the relationship between BP features and urge intensity, but not actual engagement in self-destructive behaviour. These results suggest that teaching individuals high in BP features how to better differentiate negative emotions may lessen the intensity of urges to engage in self-destructive behaviour.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Alexander Chapman
Department: 
Arts & Social Sciences: Department of Psychology
Thesis type: 
(Thesis) M.A.

Perceptual Salience and Its Consequences on Attentional Object Selection

Date created: 
2017-03-31
Abstract: 

This thesis investigated the effects of salience on visual object selection, and focused on whether salience impacts the visual system’s ability to process multiple items at the same time (parallel selection) or one-at-a-time (serial selection). Chapter 2 consists of two experiments that used an ERP component, the N2pc, to track the deployment of attention in a visual search task with highly dissimilar distractors. Although the time to find the target increased with the number of distractors, observers were able to select the target at the same time, regardless of the size of the search display. This suggests that task relevance can make otherwise non-salient items “pop out” at the level of attentional selection. Chapter 3 comprises a single experiment in which attentional selection was measured overtly, using eye tracking, as observers inspected and compared two singletons of differing salience. Discreet eye movements were made from one singleton to the other and the order of inspection was strongly biased by target salience, with the initial saccade being made to the more salient singleton on the vast majority of trials. This suggests that, in the absence of top-down control, the order of attentional selection is dictated by salience. Finally, Chapter 4 consists of three variants of the same two-singleton search task used in Chapter 3. The first experiment replicated Chapter 3 but with attentional selection tracked covertly via the N2pc. In the next two experiments, task parameters were manipulated to encourage slower shifts of attention from one singleton to the other and to encourage the initial inspection of the less salient singleton. Attentional object selection was purely serial in some cases and partially parallel in others. The biasing effect of salience could also be subverted, such that the less salient item was selected first, however that item was not selected as rapidly as the more salient item. Chapter 4 thus reveals that (i) the earliest time at which an item becomes available for attentional selection depends on its relative salience, and (ii) the speed of attentional redeployment varies with the nature of the response required.

Document type: 
Thesis
File(s): 
Senior supervisor: 
John McDonald
Department: 
Arts & Social Sciences: Department of Psychology
Thesis type: 
(Dissertation) Ph.D.

Endocrine response to social rejection: The effect of testosterone and cortisol on pain sensitivity

Date created: 
2017-03-30
Abstract: 

An expanding body of literature suggests that common neural underpinnings governing physical and social pain are evolved adaptations that punish social disengagement by using pain as a signalling mechanism for social rejection. Such a mechanism is necessary in the face of fitness benefits afforded by group living from which a ubiquitous need to belong has grown. Salivary testosterone and cortisol were examined in the context of fluctuating pain sensitivity in response to a social evaluation with a confederate. It was expected that a greater evolutionary prescribed tendency to seek interpersonal support would result in physiological responses to rejection in females leading to reductions in pain sensitivity. While non-significance was found for cortisol, results implicate testosterone as an important factor in altering sensitivity after social interactions in men. This relationship between testosterone and pain may be a function of dominance and increased status seeking resulting from acceptance in a social interaction.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Neil Watson
Department: 
Arts & Social Sciences: Department of Psychology
Thesis type: 
(Thesis) M.A.

Distinguishing between primary and secondary callous-unemotional features in youth: The role of emotion regulation

Date created: 
2017-02-27
Abstract: 

Background: Research on youth with callous-unemotional features (CU features; e.g., lack of empathy) has historically categorized these behaviors as biologically-driven and homogeneous across development. However, an early model proposed that two subtypes of CU features exist with different etiological factors. The first, or ‘primary’ group, has a genetically based deficit in emotion processing, resulting in a diminished sensitivity to others’ emotional cues. The ‘secondary’ CU group is conceptualized as an adaptation to environmental factors such as maltreatment and are characterized by an affective deficit produced by these powerful environmental factors. Secondary youth are typically classified or grouped based on the presence of co-occurring anxiety symptoms. Understanding the presentation of regulation strategies among CU variants may give us further insight into the different pathways to their development. In addition, due to the high number of samples that have relied on justice-involved males, there is a paucity of research on gender differences across the variants. Purpose: The aim of the current study was to evaluate whether distinct groups of youth may be identified in a clinical sample by using measures of affect dysregulation and suppression, anxiety symptoms and experience of maltreatment. It was also to examine whether these distinct groups were consistent across males and females. Method: Participants (N = 418; 56.7% female) ranged in age from 12 to 19 (M = 15.04, SD = 1.85) and were drawn from the baseline of a large clinical sample. Results: A Latent Profile Analysis (LPA) was conducted using five indicators including affect regulation, suppression, anxiety, CU features, and maltreatment. The best fitting model, a 4-class solution, had a significant Lo-Mendell-Rubin (p= .003), an acceptable entropy score (.78), and classification probabilities that suggested accuracy and good separation. The four groups to emerge included a low, anxious, primary CU, and secondary CU group. Gendered LPAs found a 4-class model fit for both males and females (entropy= .866). Gender did not moderate other outcomes of interest. Discussion: This study extends previous literature by including the underlying process of dysregulated affect to the model in identifying primary and secondary subgroups and examining gender. Clinical implications are discussed.

Document type: 
Thesis
File(s): 
Senior supervisor: 
Marlene Moretti
Department: 
Arts & Social Sciences: Department of Psychology
Thesis type: 
(Dissertation) Ph.D.