<p>This thesis aimed partly to examine the effects of gender on conversation dynamics, partly to investigate whether interaction between participants with contrasting opinions promotes cognitive development on a moral task. Another objective was to explore whether particular conversational features of interaction would have any impact upon a pair’s joint response or on each child’s moral development. The conversations were coded with regard to simultaneous speech acts, psychosocial behaviour and types of justifications used. The results show no gender differences regarding psychosocial processes, but the boys used more negative interruptions, more overlaps and significantly proportionately more justifications in the form of assertions than the girls in the study. Gender differences were often more pronounced in same-gender as opposed to mixed-gender pairs, but children also altered their behaviour to accommodate to the gender of their conversational partner. Children who participated in the interaction phase of the study showed more overall progress on an eight-weeks delayed post-test than those who did not. However the only conversational feature that was related to the outcomes of conversation and development was the use of expiatory force justifications which were associated with a more advanced reply immediately after interaction as well as two weeks later.</p>

Thesis (Ph.D. (Education))--North-West University, Potchefstroom Campus, 2006.

Thesis (Ph.D.)--Antioch University, 2006. / Title from PDF t.p. (viewed Mar. 27, 2007). Advisor: Alan Guskin, Ph.D. Keywords: late life learning, cognitive strategies, mental acuity, benefits of learning, lifespan learning, importance of learning. Includes bibliographical references (p. 217-227).

The purpose of this study is to examine how educators who teach in schools that face challenging circumstances understand child development and the school context, and how their understanding of child development is manifested through non-academic responses to these challenging circumstances. Using mixed methods to explore and compare the results of survey data (N = 209) with interview data (N = 48) this study examines 10 schools that face challenging circumstances that have also demonstrated trends of success on provincially administered standardized assessments. Analysis reveals the findings that educators understand the challenging circumstances their students face to be developmental in nature, that educators’ believe that these challenges involve students’ physical, social-emotional, and cognitive development, and that educators respond to these challenges by implementing non-academic and co-curricular programs that are developmentally based. This study finds that all 10 schools have implemented developmental programs that foster the success of students. These findings suggest that educators offset the developmental disadvantages their students face as a result of the community, school, and their home environments. This study finds that these educators believe students’ social-emotional development is intertwined with student cognitive development. Further, these educators have expanded the traditional performance-based construct of student “success” to include a range of success that includes child social-emotional developmental success, and in expanding their understanding of student success, have arrived at an innovative, developmentally-based approach to facing challenging circumstances in schools.

The current research examined whether nonword repetition (NWR) tasks, designed to measure phonological short-term memory, are also influenced by familiarity with lexical representation of a given language. In Study 1, children with and without exposure to Hebrew were administered a NWR task based on the Hebrew language structure (HNWR). On the HNWR, participants with Hebrew exposure significantly outperformed participants who had no familiarity with any Semitic language. This indicates that long-term phonological and lexical knowledge can be used to aid NWR performance. Study 2 investigated whether a NWR task based on a foreign language could minimize the lexicality effect. English speaking undergraduate students rated the less familiar HNWR task to be lower in wordlikeness than English-like NWR tasks. These findings demonstrate that regardless of language background a NWR task based on an unfamiliar language structure is a more valid measure of the phonological processing skills required for vocabulary acquisition.

Deletion (Williams-Beuren syndrome (WBS)) and duplication (Dup7q11.23) of a common interval spanning 26 genes on chromosome 7q11.23 cause disorders with a spectrum of clinical, cognitive and behavioural symptoms. Studies of individuals with atypical deletions have implicated two genes, GTF2IRD1 and GTF2I. Here I describe the behavioural characterization of mice hemizygous for Gtf2i, or Gtf2ird1 and Gtf2i together, as well as mice with additional Gtf2i copies. Dosage changes in Gtf2i were associated with working memory impairment and separation anxiety, and possibly with general anxiety and repetitive behaviours. A potential cause of these phenotypes was found in brain tissue, where subcellular localization of the calcium channel TRPC3, which is regulated by GTF2I, was found to be altered. Collectively, these results provide a better understanding of the contributions of GTF2I to the cognitive and behavioural profile of WBS and Dup7q11.23 and identify a potential biological mechanism that may underlie some of the symptoms.

The current research examined whether nonword repetition (NWR) tasks, designed to measure phonological short-term memory, are also influenced by familiarity with lexical representation of a given language. In Study 1, children with and without exposure to Hebrew were administered a NWR task based on the Hebrew language structure (HNWR). On the HNWR, participants with Hebrew exposure significantly outperformed participants who had no familiarity with any Semitic language. This indicates that long-term phonological and lexical knowledge can be used to aid NWR performance. Study 2 investigated whether a NWR task based on a foreign language could minimize the lexicality effect. English speaking undergraduate students rated the less familiar HNWR task to be lower in wordlikeness than English-like NWR tasks. These findings demonstrate that regardless of language background a NWR task based on an unfamiliar language structure is a more valid measure of the phonological processing skills required for vocabulary acquisition.

Deletion (Williams-Beuren syndrome (WBS)) and duplication (Dup7q11.23) of a common interval spanning 26 genes on chromosome 7q11.23 cause disorders with a spectrum of clinical, cognitive and behavioural symptoms. Studies of individuals with atypical deletions have implicated two genes, GTF2IRD1 and GTF2I. Here I describe the behavioural characterization of mice hemizygous for Gtf2i, or Gtf2ird1 and Gtf2i together, as well as mice with additional Gtf2i copies. Dosage changes in Gtf2i were associated with working memory impairment and separation anxiety, and possibly with general anxiety and repetitive behaviours. A potential cause of these phenotypes was found in brain tissue, where subcellular localization of the calcium channel TRPC3, which is regulated by GTF2I, was found to be altered. Collectively, these results provide a better understanding of the contributions of GTF2I to the cognitive and behavioural profile of WBS and Dup7q11.23 and identify a potential biological mechanism that may underlie some of the symptoms.

The purpose of this study is to examine how educators who teach in schools that face challenging circumstances understand child development and the school context, and how their understanding of child development is manifested through non-academic responses to these challenging circumstances. Using mixed methods to explore and compare the results of survey data (N = 209) with interview data (N = 48) this study examines 10 schools that face challenging circumstances that have also demonstrated trends of success on provincially administered standardized assessments. Analysis reveals the findings that educators understand the challenging circumstances their students face to be developmental in nature, that educators’ believe that these challenges involve students’ physical, social-emotional, and cognitive development, and that educators respond to these challenges by implementing non-academic and co-curricular programs that are developmentally based. This study finds that all 10 schools have implemented developmental programs that foster the success of students. These findings suggest that educators offset the developmental disadvantages their students face as a result of the community, school, and their home environments. This study finds that these educators believe students’ social-emotional development is intertwined with student cognitive development. Further, these educators have expanded the traditional performance-based construct of student “success” to include a range of success that includes child social-emotional developmental success, and in expanding their understanding of student success, have arrived at an innovative, developmentally-based approach to facing challenging circumstances in schools.

Young children’s attention to a variety of object features has been studied. However, very few studies have examined young children’s understanding of object weight. In order to investigate developmental changes in perception and categorization of weight, three tasks were given to 59 18-month-old to 3-year-old children. Three age groups (20; 27 and 34 months old) were analyzed for the final results. The first two tasks used a familiarization and novelty preference paradigm in which attention was assessed by measuring each child’s looking time. The first task’s goal was to evaluate young children’s ability to discriminate objects on the basis of weight. Children were familiarized with an object of one weight and then tested with an identical looking object that had a novel weight. Half of the subjects were familiarized to a heavy weight and half to a light weight object. Results showed a decrease in looking time over the familiarization trials (p = .0001) and an increase in attention to the novel weight (p = .0001). Thus, all children in the first task were able to discriminate object weight. Additional analyses for the first task assessed physical discrimination of object weight by examining the amount of arm movement each child exhibited within 250 milliseconds after taking an object. A significant difference in arm movement was found between the last familiarization and novel weight trials of the heavy (p = .0097) and light (p = .0001) conditions. The second task’s goal was to evaluate children’s ability to attend to object weight when appearance varies. Children were familiarized to four objects that had the same weight but differed in appearance. Half of the subjects were familiarized to heavy objects and half to light objects. After familiarization, the children were tested with one object that had the same weight but a different appearance and another object that had the same appearance but a different weight. Results revealed that the children’s looking time decreased over the familiarization trials (p = .0001). Analyses of test trials revealed that only the two older age groups had significant novelty preference scores for both the new weight and new appearance trials. The third task used a balance scale to measure understanding of weight by observing a child’s ability to pick a heavy object to make a balance scale tip. Children were given a light and heavy object with the same appearance and asked to choose which one would tip the balance scale. Results showed that only 34 month olds had significantly more correct trials (p < 0.05). In conclusion, the study’s results indicated that all young children are capable of discriminating object weight when familiarized to one object but that only the two older age groups were significantly capable of doing this when familiarized to more than one object. Results also indicated that only 34 month olds were capable of using weight differences in a more functional way, namely to tip a balance scale.