Attentional abnormalities are one of the earliest signs of Autism Spectrum Disorders (ASD). Despite flourishing attention studies in autism, relatively little is known about attentional performance among young children with high-functioning autism (HFA). The present study compared 23 preschool children with HFA and 28 typically-developing children on attention network efficiencies, selective attention to social or non-social information and attention switching, with age, cognitive and language abilities matched or controlled. Compared with typically-developing children, young children with HFA showed comparative attention network efficiencies, slower orienting to face and better attention switching. Alternative explanations for their strength in attention switching are given based on superior focused attention to visual details and hyper-systemizing skills. Implications on future research and practice are discussed. / published_or_final_version / Educational Psychology / Master / Master of Social Sciences

No description available.

No description available.

The chronic and severe executive functioning (EF) and self regulation deficits experienced by children with fetal alcohol spectrum disorders (FASD) are well documented and EF and self regulation have been identified as core targets for intervention. The goals of this dissertation were to: (i) examine the effects of a self regulation treatment for children with FASD on a range of EF measures (ii) examine neural markers of treatment outcome and determine if functional magnetic resonance imaging (fMRI) can differentiate treatment responders from nonresponders; (iii) determine if treatment effects generalize to child compliance and qualitatively examine the treatment process. Twenty-five children with FASD participated. Using a wait-list control design children were assigned to an immediate treatment (TXT; n = 12) or delayed treatment control (DTC; n = 13) condition. All children received an evaluation of EF and fMRI at baseline and 12-week follow-up. Parents also completed questionnaires assessing EF and behavior as well as a feedback questionnaire upon completion of treatment. A subset of parents tracked compliance over the course of their child’s therapy. For the TXT group only, parent questionnaires were readministered at 6 month follow-up. At 12-week follow-up, children in the TXT group displayed significant improvements in inhibitory control and social cognition. Additionally, parents reported improved behavioral and emotional regulation. This improvement, along with a further improvement in parent-rated inhibitory control, was maintained at the 6-month follow-up. Neuroplastic changes were also observed as the TXT group showed increased BOLD response in the right prefrontal cortex (PFC) and left caudate on a task of inhibitory control. When treatment responders were compared to nonresponders a pattern of increased BOLD response was found bilaterally in the PFC and left caudate. Compliance tracking revealed that self regulation therapy generalized to improved child compliance at home. Qualitative analysis indicated that perceived clinician competence, caregiver insight about child’s problems and caregiver perceptions of child’s insight about their problems, were the most commonly endorsed themes by caregivers. Results from this research signify that children with FASD are responsive to psychotherapy and following a brief intervention, showed improvements in self regulatory abilities that generalize to other EF areas and parent-reported behaviors.

Minor physical anomalies (MPA) are mild congenital malformations in external physical abnormalities that are observed in neurodevelopmental disorders such as velocardiofacial syndrome (more commonly known as 22q11.2 deletion syndrome), autism and schizophrenia. It has been reported that about three-quarters of MPAs can be found in the craniofacial region, such as low-seated ears, high-steepled palate, altered interorbital distance. Furthermore, both eye and brain development are tightly linked, and interorbital distance and optic chiasmic angle in adulthood are perinatally fixed. Therefore my study investigated MPAs of the optic system in two neurodevelopmental disorders, 22q11.2 deletion syndrome and autism spectrum disorders (ASD). The four selected MPAs included 1) inter-orbital distance, 2) the optic chiasmic angle, 3) anterior extension of optic nerves ‘a’, and 4) posterior extension of optic nerves ‘b’. They were investigated in two individual studies, the first comprising 17 adults with ASD and 21 controls while the second comprised 27 adults with 22q11.2 deletion syndrome and 28 controls. Their MRI scans were analysed with respect to the MPAs. The main finding was that adults with ASD had significantly larger total brain volume which was positively correlated with the anterior extension of optic nerves ‘a’, but not the other optical MPAs. This suggested that the larger brain volume was more related to frontal brain enlargement. As no relevant significant results were obtained in the controls nor adults with 22q11.2 deletion syndrome, such finding appears pertinent to ASD adults, rather than that to a genetic neurodevelopmental disorder. However, this finding is only preliminary, and other neurodevelopmental disorders should be included for comparison with ASD and healthy controls. The use of MRI appears to be a feasible tool to assess MPAs. Future work will focus on whether these observations can be replicated across the life-span by evaluating these parameters in children with ASD, as well as adults with other neurodevelopmental disorders. / published_or_final_version / Psychiatry / Master / Master of Philosophy

No description available.

No description available.

A serious consequence of maternal consumption of alcohol during pregnancy is the fetal alcohol syndrome (FAS): characterized by growth deficiency (both pre- and post-natal), craniofacial dysmorphology and central nervous system (CNS) dysfunction. However, in the absence of the characteristic facial features, and without confirmed history of alcohol exposure, clinical diagnosis remains a significant challenge. Recently, the term fetal alcohol spectrum disorders (FASD) has been adopted to encompass all diagnoses relating to a history of prenatal alcohol exposure. The purpose of this study was to test the following three general hypotheses: Children with FASD 1) demonstrate specific deficits in oculomotor control that can be measured using saccadic eye movement tasks, 2) display specific deficiencies in multiple domains of executive function that can be determined using standardized neuropsychological tasks, and 3) reveal deficits in oculomotor control that correlate with deficiencies in executive function as measured using standardized neuropsychological tasks. A preliminary study revealed significant deficits in saccadic eye movement tasks and provided the foundation for a large, multi-centered study assessing oculomotor control and neuropsychological function in children with FASD. A mobile laboratory was created, which facilitated recruitment of 92 control subjects and 89 subjects with FASD. We found significant evidence for oculomotor deficits across multiple outcome measures following the saccadic eye movement experiments, especially for oculomotor tasks that probe aspects of executive function. Additionally, children with FASD exhibited performance deficits in neuropsychological tasks that assess planning, attention, spatial working memory and strategy; cognitive skills also included within the domain of executive function. Finally, significant correlations between these two objective measures were found for children with FASD, which were not evident in the control sample. These findings are consistent with significant frontal lobe dysfunction. This is an exciting area of research that may hold promise in developing effective screening tools that can assist in the diagnosis of individuals with a history of prenatal alcohol exposure. / Thesis (Ph.D, Neuroscience Studies) -- Queen's University, 2008-08-28 15:41:20.595

The current studies addressed two questions regarding early social behaviour in children with Autism Spectrum Disorders (ASD) that have not yet been directly explored. In Study 1 we examined the hypothesis that impaired imitation in this group may reflect a diminished social motivation to engage, rather than a core deficit in imitation. Young children with and without ASD engaged in imitation tasks during which controlled manipulations of reward (social and non-social) were administered for target behaviours. Children with ASD displayed increased levels of imitation with the incentive of an external reward in comparison to when this reward was absent. There was no differential impact of social versus non-social rewards. Typically developing (TD) children performed similarly, irrespective of whether or not reward was administered. We suggest that young children with ASD may be capable of imitating when appropriate incentives are present. Study 2 explored the breadth of social challenges faced in young children with ASD by examining a later-developing domain of social functioning that may be compromised by early social difficulties. We explored the tendency of children with ASD to engage in helping, sharing, and comforting behaviour in situations where the need for the prosocial behaviour was displayed and in perceptually similar situations where the need was absent. Children with ASD displayed low levels of helping and sharing, but provided comfort at levels consistent with TD children. For both comforting and sharing, children with ASD successfully discerned situations where a need was present from when it was not and adjusted their behaviour accordingly. We suggest that children with ASD may require different ‘conditions’ to engage in social behaviours at the same level as their TD peers and suggest future research to this end. / Thesis (Ph.D, Psychology) -- Queen's University, 2012-09-27 22:10:12.095

The chronic and severe executive functioning (EF) and self regulation deficits experienced by children with fetal alcohol spectrum disorders (FASD) are well documented and EF and self regulation have been identified as core targets for intervention. The goals of this dissertation were to: (i) examine the effects of a self regulation treatment for children with FASD on a range of EF measures (ii) examine neural markers of treatment outcome and determine if functional magnetic resonance imaging (fMRI) can differentiate treatment responders from nonresponders; (iii) determine if treatment effects generalize to child compliance and qualitatively examine the treatment process. Twenty-five children with FASD participated. Using a wait-list control design children were assigned to an immediate treatment (TXT; n = 12) or delayed treatment control (DTC; n = 13) condition. All children received an evaluation of EF and fMRI at baseline and 12-week follow-up. Parents also completed questionnaires assessing EF and behavior as well as a feedback questionnaire upon completion of treatment. A subset of parents tracked compliance over the course of their child’s therapy. For the TXT group only, parent questionnaires were readministered at 6 month follow-up. At 12-week follow-up, children in the TXT group displayed significant improvements in inhibitory control and social cognition. Additionally, parents reported improved behavioral and emotional regulation. This improvement, along with a further improvement in parent-rated inhibitory control, was maintained at the 6-month follow-up. Neuroplastic changes were also observed as the TXT group showed increased BOLD response in the right prefrontal cortex (PFC) and left caudate on a task of inhibitory control. When treatment responders were compared to nonresponders a pattern of increased BOLD response was found bilaterally in the PFC and left caudate. Compliance tracking revealed that self regulation therapy generalized to improved child compliance at home. Qualitative analysis indicated that perceived clinician competence, caregiver insight about child’s problems and caregiver perceptions of child’s insight about their problems, were the most commonly endorsed themes by caregivers. Results from this research signify that children with FASD are responsive to psychotherapy and following a brief intervention, showed improvements in self regulatory abilities that generalize to other EF areas and parent-reported behaviors.