OBJETIVO: Investigar e comparar a aprendizagem de uma habilidade motora de alta demanda de planejamento em sujeitos pós-Acidente Vascular Encefálico (AVE) em função do lado da lesão. MÉTODO: Participaram do estudo 22 indivíduos pós-AVE para compor o grupo experimental (GE), sendo 10 LD e 12 LE, e 14 sujeitos saudáveis para o grupo controle (GC). Os critérios de inclusão foram: 40 a 75 anos de idade, lesão em circulação anterior, crônicos, único evento vascular, destros e Mini Exame de Estado Mental (MEEM) com pontuação acima de 23. A tarefa consistiu em realizar a inserção de uma barra em um orifício, o mais rapidamente possível. O estudo foi composto de duas fases, sendo de aquisição (AQ) com 50 tentativas e de testes de retenção em curto (RET1), longo prazo (RET2) e transferência (TR) com 10 tentativas cada. Foram realizadas análises intra (GC, GE, LD e LE) e intergrupos por meio da ANOVA two-way (grupos X blocos) com medidas repetidas no segundo fator, seguida do post hoc de Tukey. O nível de significância adotado foi de 0,05. RESULTADOS: Houve déficit na aprendizagem do GE nas comparações do nível de desempenho entre o último bloco da AQ com os testes de RET2 e TR, que se apresentou dependente do lado da lesão. Quando comparado com o GC e com LD, o LE apresentou deterioração na RET2. CONCLUSÃO: Há diferença entre o GE e GC no que se refere à aprendizagem de uma habilidade motora com alta demanda de planejamento, mensurada por meio do teste de RET em longo prazo, sendo esta diferença dependente do lado da lesão. O grupo com LE apresentou os maiores déficits na aprendizagem / OBJECTIVE: To investigate and compare the motor learning of a motor skill with high planning demand in post-stroke subjects according to the hemisphere side damage. METHOD: The study comprised twenty-two post-stroke individuals in the experimental group (EG), 10 right hemisphere damaged (RHD) and 12 left hemisphere damaged (LHD), and 14 health subjects in the control group (CG). The inclusion criteria were: age between 40 and 75 years old, anterior circulation damage, chronic stage, single stroke, right-handed and Mini Mental State Exam (MMSE) with score over 23 points. The task consisted of inserting a bar into a hole, as fast as possible. The study consisted of two phases, acquisition (ACQ) with 50 trials and retention tests in short-term (RET1), long-term (RET2) and transfer (TR), with 10 trials each. Analyses within group (CG, EG, RHD and LHD) and between groups were performed by ANOVA two-way (groups x blocks) with repeated measures in the second factor followed by post-hoc of Tukey test. The significant level adopted was 0,05. RESULTS: There was a decrease in the EG learning when the level of performance on the last ACQ block was compared with RET 2 and TR tests, dependent on the hemisphere damage side. CONCLUSION: There are differences on motor learning of a motor skill with high planning demand between EG and CG, especially measured at the RET2. LHD subjects showed significant deterioration in motor learning at the RET2

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The relationship of current manual preference (phenotypic handedness) and family history of handedness (genotypic handedness) to memory for imageable stimuli was studied. The purpose of the study was to test the hypothesis that genotypic handedness was related to lessened cerebral lateralization of Paivio's (1969) dual memory systems. The structure of memory was not at issue, but the mediation of storage and retrieval in memory has been explained with reference to verbal or imaginal processes. Verbal mediation theories and supporting data were reviewed along with imaginal theories and supporting data for these latter theories. Paivio's (1969) dual coding and processing theory was considered a conceptual bridge between the competing positions.

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No description available.

There are currently many statements about the effects of hemispheric specialization of the brain upon children's cognitive processing and therefore, upon content or modes of instruction. Before educators can accept or even test these statements, it is important to devise easy-to-use measures of hemispheric functioning and to study their relationship to established measures of achievement and linguistic and cognitive development. Current research in brain functioning has indicated that conjugate-lateral eye movement direction (the direction in which a person looks while thinking) can be a sensitive indicator of which cerebral hemisphere is initially activated. The central purpose of this investigation was to analyze the effects of the stimulus characteristics of reflective questions of verbal and spatial nature on the conjugate-lateral eye movement (CLEM) behavior of right-handed children from fourth, fifth, and sixth grades. A major objective was to determine whether data on children’s CLEM responses would better support a model of characteristic individual differences or a model of differentiation by question type. The testing instrument devised for this purpose was the Reflective Questions Test (RQT) which included both Verbal and Spatial subtests. In an experimenter-facing-subject paradigm with a sample of 60 (30 boys, 30 girls), conjugate-lateral eye movement was found to be easily observable and question type was found to influence the direction of eye movement, thus supporting a differentiation by question type model. Verbal questions elicited significantly more rightward CLEMs than spatial questions and spatial questions elicited significantly more leftward CLEMs than verbal questions fn the sample studied. No significant sex differences were found. These results seem to be consistent with the neuropsychological theory that once hemispheric specialization has occurred with normal right-handed children, the left hemisphere mediates language functions and the right hemisphere mediates spatial functions. Examining the number of directionally appropriate CLEM responses, a two-way analysis of variance (verbal and spatial question type by grade level) yielded no main or interaction effects. The results suggest that although children in grades four, five, and six tended to gaze in different directions while responding to verbal than while responding to spatial questions, the rate of responses appropriate to the question (gazing in the direction predicted) was no greater for verbal than for spatial questions. Further, the means for question types were almost identical across grade levels for CLEM responses to verbal and to spatial questions, supporting a no-change model of neuropsychological function, which contends that within the later childhood years, hemispheric specialization is well developed. The Reflective Questions Test was found to have high inter-rater reliability (.94) and temporal stability (.78). These results indicate that the RQT produced reliable and stable results for the sample studied and support the appropriateness of the RQT for future refinement and use in educational research of this type. Correlations of the RQT with other measures of linguistic and cognitive development, and educational ability were found to be nonsignificant. These results suggest that hemispheric activation as indexed by the RQT at this age range may be largely independent of measures traditionally associated with school performance. The results of this investigation have provided normative data on normal right-handed children, thereby providing a comparative basis for future research with children of the same age from other populations such as the learning disabled. / Ed. D.

Two experiments were designed to selectively prime each cerebral hemisphere to evaluate Kinsbourne's selective activation model. The left hemisphere priming manipulation for both experiments was subvocal rehearsal of neutral words, whereas right hemisphere primes consisted of imagery (Experiment 1) and subvocal rehearsal of affective words (Experiment 2). Reaction time performance in the visual field contralateral to the activated hemisphere was hypothesized to improve. No evidence supporting this hypothesis was found in these experiments, though experimental tasks had significant interference effects. In Experiment 1, non-specific interference effects were found across visual fields for both experimental tasks, suggesting the hemispheres were not preferentially recruited. Right visual field interference was observed in Experiment 2 for subvocal rehearsal, particularly of affective words, implicating selective left hemisphere activation. This finding indicates an overloading of the left hemisphere's affective perceptual capabilities. Significantly, no equivalent right hemisphere effects were observed, suggesting different functional space characteristics for affect perception across the hemispheres. These findings appear to substantiate a structural rather than activational model of functional cerebral asymmetries, but interference effects do unequivocally support either model. Furthermore, in Experiment 2, neutral faces were perceived as angry equally often in both visual fields, though neutral faces in the control and affective rehearsal conditions were more frequently perceived as angry relative to the neutral rehearsal condition. Methodological issues are presented to account for these findings. / Master of Science

The Dichotic Emotional Words Tape developed by Bryden and MacCrae (1989) was used to assess cerebral asymmetry for propositional and nonpropositional speech as a function of verbal fluency. Forty-five right-handed subjects with normal auditory acuity for pure tones were assigned to a verbal fluency classification based on scores on the FAS test (Borkowski, Benton, & Spreen, 1967). After being assigned to a fluency category, subjects were instructed to listen for a word (bower, dower, power, or tower) or affective tone (happy, sad, angry, or neutral). The most important findings of this study were the main effects of fluency (higher, middle, and lower), stimulus type (word and affect), and focus or intention (focus left and focus right). Subjects higher in fluency exhibited significantly greater REA and LEA scores than subjects lower in fluency. For stimuli presented to the right ear, scores for words were significantly greater than scores for affect. However, for stimuli presented to the left ear, scores for affect were significantly greater than scores for words. Focus left instructions led to increases in LEA scores, while focus right instructions led to increases in REA scores. Directions for future research are discussed. / Master of Science

Hemispheric specialization for language processing is demonstrated as a left hemispheric function for most normal hearing right-handed subjects. Hearing impaired subjects, however, do not demonstrate a predictable hemispheric specialization for language processing. This research used a matched letter pair stimulus presented tachistoscopically to four male and four female right-handed, profoundly deaf children who use cued speech to communicate. Analysis of the test data shows a small significant trend towards left hemispheric specialization for language processing. A case-by-case review reveals that four subjects demonstrated left hemispheric specialization for language processing, two subjects demonstrated right hemispheric superiority for language processing, and two subjects did not demonstrate superiority for language processing in either hemisphere. A larger sample size would be required to determine if the cued speech subjects develop hemispheric specialization the way normal hearing subjects do or whether they develop the inconsistent pattern of specialization of other deaf subjects. / M. S.

M.A. / The study aims to determine whether statistically significant differences exist between boys with attention deficit hyperactivity disorder (ADHD) and boys without ADHD with regard to hemispheric language lateralization and the laterality of various modalities (handedness, eyedness and footedness). According to the literature, a possible connection exists between abnormal lateralization patterns and various developmental disorders (Corballis, 1983; Geschwind & Behan, 1982; Hiscock, 1988, McFarland, 1981; Turkewitz, 1988). Lateralization in the current study refers to hemispheric language specialisation, hand dominance, foot dominance and eye dominance. In most people these functions are lateralized to the one side of the body by the age of seven (Kalat, 1995; Kolb & Whishaw, 1996). They typically manifest a dominant left hemisphere for language and a right-sided dominance for handedness, footedness and eyedness. The result is a dominant left hemisphere, due to the left side of the brain controlling the right side of the body. Some children however manifest insufficient or poor lateralization of these functions. For purposes of this study, it would imply that the functions of language specialisation, handedness, footedness and eyedness are not all lateralized to one side of the body. A possible connection between this poor or insufficient lateralization and ADHD might exist. According to the DSM IV (1997) the essential feature of ADHD is a persistent pattern of inattention and/or hyperactivity/impulsivity that is more frequent and severe than is typically observed in individuals at a comparable level of development. Some of these symptoms causing impairment must have been present before age seven, although many individuals are only diagnosed after the symptoms have been present for a number of years. Impairment resulting from the symptoms should be present in at least two settings, for example, at school and at home. Clear evidence must exist of interference with developmentally appropriate social, academic, or occupational functioning. An empirical study was conducted in order to compare the hemispheric language specialisation, handedness, eyedness and footedness of the various subjects. The subjects consisted of 20 ADHD boys (8 -12 years) who met the criteria of the DSM IV and 20 Non-ADHD boys (8-12 years) without any learning problems. Various interference variables were controlled in the selection of the subjects (see section 5.2.3) Kimura's dichotic listening technique was used to measure hemispheric language specialisation and the Harris-test for Lateral Dominance was used to measure handedness, eyedness and footedness. Wilks's lambda, Pearson's chi-quadrant and Student's t-tests were used during statistical analysis of data. Results indicated statistically significant differences between ADHD boys and non-ADHD boys with regard to hemispheric language specialisation, handedness and footedness. Overall, the results indicated that the ADHD boys are not as strongly lateralized as the non-ADHD boys. The non-ADHD boys showed a stronger left hemispheric language specialisation, right hand dominance and right foot dominance. No statistical differences were recorded with regard to eyedness. The current study provides possible theoretical support for the theory that a connection exists between poor or insufficient lateralization patterns and children with ADHD. However, the study only focused on white boys between the ages of 8-12 years. Further studies involving different age groups, cultures and gender are recommended.