Current theories of auditory attention are largely based upon studies examining either the presentation of a single auditory stimulus or requiring the identification and labeling of stimuli presented sequentially. Whether or not these theories apply in more complex ecologically-valid environments where multiple sound sources are simultaneously active is still unknown. This study examined the pattern of neuromagnetic responses elicited when participants had to perform a search in an auditory language-based `scene` for a stimulus matching an imperative target held in working memory. The analysis of source waveforms revealed left lateralized patterns of activity that distinguished target present from target absent trials. Similar source waveform amplitudes were found when the target was presented in the left or right hemispace. The results suggest that auditory search for speech sounds engage a left lateralized process in the superior temporal gyrus.

Previous research has shown that individuals endorsing inattention and hyperactivity-impulsivity have deficient performance on tasks tapping different aspects of attention. Although there is empirical evidence suggesting that the behavioral domains of inattention and hyperactivity-impulsivity are linked to functioning of independent and separate brain areas and neurotransmitter systems, cognitive characterization of adults presenting with problems within these domains is not complete. The aim for this study was to identify the cognitive correlates of the core behavioral domains that define the diagnosis of AD/HD (i.e., inattention and hyperactivity-impulsivity) in a sample of college students, utilizing a computerized attention task, the Attention Network Test (ANT). Different ANT task components have been found to activate separate brain areas linked to the functioning of alerting, orienting and executive attention, and have the potential to provide an indication of the efficiency of these brain networks. In addition to completing the ANT, the participants filled out questionnaires covering common symptoms of adult AD/HD, anxiety and depression. Hierarchical regression analyses revealed that there were no reliable relationships between self-reported symptoms of current inattention and hyperactivity-impulsivity and ANT performance. Further, self-reported depression and/or anxiety did not seem to impact the efficiency of attention networks to a significant degree in this study sample. Gender proved to be the most consistent predictor of ANT performance. Female gender was related to poorer executive attention efficiency. An exploratory ANCOVA revealed that individuals reporting high levels of impulsivity and emotional lability had poorer executive attention efficiency in comparison to those reporting these behaviors and problems to a lesser extent. Future research is needed in order to further explore the relationship between ANT performance and behavioral expressions of adult AD/HD and other neurological and psychiatric conditions.

Thesis (M.A.)--York University, 2008. Graduate Programme in Psychology. / Typescript. Includes bibliographical references (leaves 34-39). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR45928

Thesis (M.Ed.) - University of KwaZulu-Natal, Durban, 2008. / Full text also available online. Scroll down for elctronic link.

Thesis (Ph. D.)--Lehigh University, 2004. / Includes vita. Includes bibliographical references (leaves 114-124).

Thesis (Ph.D.)--Marshall University, 2008. / Includes bibliographical references (leaves 39-43).

Thesis (Psy. D.)--Wheaton College Graduate School, Wheaton, Ill., 2002. / Abstract. Includes bibliographical references (leaves 48-53).

Thesis (M.A.)--Marshall University, 2002. / Title from document title page. Document formatted into pages; contains viii, 48 p. with illustrations. Includes bibliographical references (p. 42-43).

This thesis tests the hypothesis proposed by Liemkuhler (1994) relating to the development of a cluster of personality styles among ADHD adolescents. Liemkuhler suggests that it is a neurobiological dysfunction, through its interaction with psychodynamic and cognitive processes that predisposes the ADHD adolescent to the development of certain personality styles. An absence of appropriate intervention and support increases the risk of these personality styles developing into clinical syndromes. To determine whether differences in personality styles do exist between ADHD adolescents and adolescents without ADHD, the NED Five Factor Inventory (NEDFFI) was group administered to a sample of 25 adolescents who were previously diagnosed as having ADHD (referred to as the ' research group') and 25 controls (referred to as the ' control group') who were matched for age and educational level. Five testable hypotheses were formulated for each of the five personality scales. A comparison of each of the five scales between the research group and the control group yielded no significant result to support Liemkuhler's hypothesis. However, a comparison of the five scales within each group (either the research group or the control group) produced several significant differences. Significant correlations were also found between scales for each group. On the basis of these results it is suggested that specific differences in the facets (traits) that are measured by each of the five personality scales may exist for each group, as opposed to overall group differences in personality styles. It is further proposed that the facets that are tapped may be explained on the basis of assumed differences in the neurobiological and cognitive functioning of both groups. It is tentatively concluded that the results may provide partial support for Liemkuhler's hypothesis. However, it is acknowledged that the complexity of Liemkulher's argument warrants further and more detailed research. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2003.

There is no abstract available for this dissertation. / Department of Educational Psychology