Knowledge of the literature pertaining to patterns of performance in normal individuals is essential if we are to understand intraindividual variability in neurocognitive test performance in neuropsychiatric disorders. Twenty-five healthy individuals with a high-level of education were evaluated on a short neuropsychological battery which spanned several cognitive domains. ---Results indicated that cognitive abilities are not equally distributed within a sample of healthy, high-level functioning individuals. This may be of interest to neuropsychologists who might base clinical inference about the presence of cerebral dysfunction, at least in part, on marked variation in a patient’s level of cognitive test performance. The practice of deductive reasoning in clinical neuropsychology may be prone to false-positive conclusions about cognitive functioning in neuropsychiatric disorders where base-rates of cognitive impairments are low and pre-existing educational achievements are high.

This study examined the self-efficacy for learning beliefs of male and female youth with ADHD, and explored whether symptoms of inattention predict self-efficacy beliefs beyond internalizing symptoms and academic achievement. Thirty-one youth with ADHD (18 males, 13 females) and 31 youth without ADHD (17 males, 14 females) between the ages of 13 and 18 completed self-report questionnaires examining self-efficacy for learning, ADHD symptomatology, academic achievement, and internalizing problems. Results indicated that female youth with ADHD felt less confident in their ability to regulate their learning effectively. In addition, regression analyses with the full sample revealed that inattention predicted self-efficacy for learning beliefs beyond internalizing difficulties and academic achievement. These results suggest that youth reporting high levels of inattention may also have lower perceptions of their ability to accomplish many academic tasks that require self-regulation.

Working memory (WM), which is essential for many academic skills, has been found to predict inattentive behaviours and is a common deficit in ADHD and LD. Recent studies have suggested that WM can be improved by intensive and adaptive computerized training. The purpose of this study is to investigate the effects of a WM training program on WM, attention, behaviour and academics in adolescents with severe LD/ADHD. A total of 60 12 to 17 year olds with ADHD/LD were randomised to one of two computerized intervention programs: working memory training or math training and evaluated before and at three weeks after completion. Adolescents in the WM training group showed greater improvements in some measures of WM than those in the Math training group, but no training effects were observed on any other measures. Findings are discussed in the context of theoretical and practical implications of WM training.

While neuropsychological deficits have been reported in healthy individuals who use cannabis, data in patients with multiple sclerosis (MS) are lacking. Given that MS is associated with cognitive deterioration, the aim of this study was to determine the cognitive effects of inhaled or ingested cannabis in this population. Fifty MS patients (25 cannabis users and 25 non-users) completed the Minimal Assessment of Cognitive Function in MS battery of neuropsychological tests. Cannabis users had significantly poorer performance on measures of information processing speed, executive functions, and visuospatial perception, and were twice as likely to be classified as globally cognitively impaired. Similar results were found after controlling for potential confounding variables. This study provides evidence that prolonged cannabis use in MS patients is associated with poorer performance on cognitive domains commonly affected in this population. The therapeutic benefits patients may derive from using cannabis should be weighed against the associated cognitive side-effects.

This study investigated the experience of posttraumatic growth for breast cancer survivors who volunteered to complete a survey (N = 277). A number of participants also provided narrative responses containing their personal experiences of breast cancer (N = 100). Demographic characteristics, breast cancer variables, optimism, coping strategies, and participation in psychosocial interventions were examined in relation to posttraumatic growth as measured by the Posttraumatic Growth Inventory. Differences between those who participated in psychosocial interventions versus those who did not were examined. The relation of coping strategies utilized and optimism level to interventions accessed was also of interest. Predictors of posttraumatic growth were examined via generalized linear modeling. Finally, the narrative responses were investigated by means of content analysis. The results provided evidence that demographic characteristics (i.e., affiliation with religion and lower levels of education) and one breast cancer variable (i.e., increased number of years since diagnosis) were related to experiences of posttraumatic growth for breast cancer survivors. Use of active forms of coping, optimism level, and participation in recreational interventions were also related to posttraumatic growth. Those who participated in psychosocial interventions were more likely to be employed and have higher levels of education than those who did not access interventions. Use of several active coping strategies and one passive coping strategy increased the likelihood of accessing a number of different psychosocial interventions. Posttraumatic growth was predicated by affiliation with religion, lower levels of education, increased number of years since diagnosis, knowledge of breast cancer stage, higher levels of optimism, and use of one passive and two active coping strategies. Many of these findings support previous research, however some conflict with prior results. The narrative responses contained information regarding diagnosis and treatment, impact of breast cancer, coping with breast cancer, and support accessed. Although the negative impact of breast cancer was discussed in terms of short and long-term, positive long-term changes were also reported. A variety of coping strategies and supports were utilized by the participants as well.

Expressive Writing (EW) involves asking participants to write emotionally about stressful life events and has been associated with improvements in psychological and physical health. The purpose of the current study was to extend previous work by examining the moderating and mediating role of emotion regulation within the EW intervention. Sixty participants who had experienced a traumatic event were recruited from the community and were assigned to an EW or control writing condition. Measures assessing emotion regulation and indices of psychological and physical health were administered at baseline and one month follow-up to determine changes in symptomatology. In comparison to control writing, EW led to significant improvements in depression, emotional clarity, and to a lesser degree emotional awareness. Although no other group differences were found, all participants demonstrated significant improvements in their symptoms of posttraumatic stress, reported physical health, overall emotion regulation abilities, their ability to accept their emotions, engage in goal directed behaviour when distressed, and access emotion regulation strategies they perceive as effective. No support was found for our moderation hypothesis. However, a significant moderation was discovered revealing that difficulties engaging in goal directed behaviour when distressed moderated improvements in posttraumatic stress symptoms. Specifically, control participants with this emotion regulation deficit demonstrated significantly poorer outcomes than control participants without this deficit; in comparison to the EW group participants who improved similarly on posttraumatic stress symptoms regardless of their level of difficulties at baseline engaging in goal directed behavour when distressed. Additionally, baseline emotion regulation abilities predicted improvements on psychological health (but not physical health) outcome measures for both groups. No support was found for our mediation hypothesis. Exploratory analyses revealed that the EW group demonstrated greater emotional arousal in response to their writing in sessions 1 and 2, but that by session 3 their arousal had significantly decreased and was equivalent to that of the control group, which showed no changes in arousal across sessions. No support was found for the moderating or mediating influence of arousal on outcome. Results will be discussed within a model of emotional expression and emotion regulation and compared to the existing EW literature.

Children with fetal alcohol spectrum disorders (FASD) have deficits across many cognitive, behaviour and social domains. However, despite social difficulty being proposed as a main deficit following prenatal alcohol exposure, the nature of their deficient social behaviour is largely unknown. One process that may underlie difficulties in social functioning is poor social cognition, which refers to one’s understanding of the self, others and social world. The primary goal of this dissertation was to determine whether social cognitive deficits represent a core disability underlying the socio-behavioural problems of FASD using a bottom-up approach. The first level of this approach is represented by face processing. Global and independent face feature processing was compared between FASD and normal controls (NC) using experimental and clinical measures. Eye gaze processing was investigated next using experimental and clinical tasks. At the highest level of the bottom-up approach, social perspective taking, including theory of mind and empathy were examined, along with how these abilities related to parent-rated behaviour. Finally, the lowest level consisted of specific aspects of the social neural network. White matter in three limbic pathways was investigated using diffusion tensor imaging (DTI). Results generally supported the bottom-up approach of social cognition in FASD. These children showed impaired processing of face features, when matching mouth shapes and partially occluded identity, compared with NC. The FASD group was slower to process gaze and arrow cues, suggesting impaired attention shifting. Children with FASD also showed impairments in social perspective taking, including understanding false beliefs and empathy, and these impairments were related to parent-rated attention and social problems, and autistic-like traits. Deficits in theory of mind got worse with age in FASD and empathy showed distinct sex-related differences. Although no group differences were observed on DTI indices, groups did show different age-related changes in white matter. In conclusion, deficits at each level of the current bottom-up approach may underlie the social impairments in FASD and may contribute to their broader social behavioural phenotype. The results from this dissertation have potential to inform clinical practice and lead to more effective diagnostic and treatment approaches in FASD.

Reviews summarizing hundreds of studies cite Parent Management Training (PMT) and Cognitive-Behaviour Therapy (CBT) as some of the most effective interventions for aggressive youth (e.g., Brestan and Eyberg, 1998). However, variability in outcomes persists, and we have yet to understand why certain interventions only produce behaviour change in some children. Using a clinical sample of 57 children (53 boys, 4 girls) and their mothers enrolled in a combined PMT/CBT program, the current study examined the relation between changes in real-time parent-child interactions, and children’s externalizing outcomes from pre- to post-treatment. Results showed that dyads who were regulated in their interactions over time reported greater reductions in externalizing symptoms from pre- to post-treatment compared to dysregulated dyads. Changes in mean levels of affective content (e.g., negativity) were not associated with aggressive outcomes. Findings suggest that dyadic regulation may be an important process associated with treatment success for aggressive youth.

Research has shown that social pressure is related to treatment motivation and plays an important role in treatment engagement in adults with problematic substance use. Despite the shifts in autonomy and decision-making in emerging adulthood, the factors affecting treatment motivation (e.g., readiness to comply with treatment) and motivation to change (e.g., problem recognition and taking steps towards change) during this period have been largely ignored. In this study, 134 youth presenting to an outpatient substance abuse program completed questionnaires investigating substance use history, mental health, social pressure to reduce use and enter treatment, and motivation. Results indicated that peer pressure accounted for significant variance in internal positive and internal negative treatment motivation. Family pressure was related only to external treatment motivation. Neither social network source had a significant impact on motivation to change. Limitations, directions for future research and treatment implications are discussed.

Paediatric posterior fossa tumors are often effectively controlled with a combination of radiation, chemotherapy and surgery. However, therapeutic craniospinal radiation has been associated with widespread cognitive late effects. Working memory is one such cognitive ability that has yet to be fully examined in this clinical population. Bilateral tracts connecting the cerebellum with the DLPFC were delineated using DTI tractography in all participants, replicating the cerebrocerebellar pathway outlined in an animal model. There were observable differences in white matter integrity (quantified by DTI measures of anisotropy, and mean, axial, and radial diffusivity) of the cerebellum-DLPFC pathway in patients versus controls. Additionally, working memory deficits that were found in patients were correlated with DTI indices pertaining to the cerebellum-DLPFC pathway. Therefore, this thesis is the first to explore the possible relations between white matter integrity of this pathway following treatment for paediatric posterior fossa tumors and working memory function.