This thesis includes four projects that examine motor learning and assess novel approaches for the training and evaluation of walking. In Project 1 we study motor adaptation in children aged 8-36 months using a split-belt treadmill. Split-belt walking, in which one leg moves faster than the other, causes asymmetries in interlimb coordination. Adaptation is manifest as decreases in the asymmetries with practice, and an aftereffect (i.e., asymmetry in the opposite direction) upon the return to normal treadmill walking. Most children showed adaptation in double support time (temporal measure of interlimb coordination), but fewer showed adaptation in the spatial measures of step length and centre of oscillation. Hence, the mechanisms controlling adaptation of temporal coordination may mature before those controlling spatial coordination. In Project 2 we studied interlimb coordination and long-term training in infants aged 3-10 months. We found that most infants expressed the same type of coordination (i.e., alternate or synchronous) when kicking, a non-weight bearing movement, and when weight bearing on the treadmill. We also showed that daily practice of the non-preferred coordination in weight bearing for 1 month changed the preferred coordination for non-weight bearing movements. These findings suggest there is partial sharing of neural substrates for interlimb coordination of different leg movements in infants. In Project 3 we compared 2 methods of walking training body weight-supported treadmill training (BWSTT) and an over-ground method involving challenging practice of relevant walking skills (called skill training). Four individuals with chronic incomplete spinal cord injury (ISCI) completed 3 months of BWSTT followed by 3 months of skill training, or vice versa. We found skill training to be as effective as BWSTT at improving walking skill, speed, endurance and confidence. In Project 4 we developed a new measure of walking for ISCI, called the Spinal Cord Injury Functional Ambulation Profile (SCI-FAP). It involves the timed performance of 7 common walking tasks. The SCI-FAP has high inter-rater and test-retest reliability, and discriminative and convergent validity. Collectively the findings of this thesis will contribute to the optimization of walking training programs for adults and children with damage to the central nervous system. / Rehabilitation Science

Cross validation (CV) is widely used for model assessment and comparison. In this thesis, we first review and compare three v-fold CV strategies: best single CV, repeated and averaged CV and double CV. The mean squared errors of the CV strategies in estimating the best predictive performance are illustrated by using simulated and real data examples. The results show that repeated and averaged CV is a good strategy and outperforms the other two CV strategies for finite samples in terms of the mean squared error in estimating prediction accuracy and the probability of choosing an optimal model. In practice, when we need to compare many models, conducting repeated and averaged CV strategy is not computational feasible. We develop an efficient sequential methodology for model comparison based on CV. It also takes into account the randomness in CV. The number of models is reduced via an adaptive, multiplicity-adjusted sequential algorithm, where poor performers are quickly eliminated. By exploiting matching of individual observations, it is sometimes even possible to establish the statistically significant inferiority of some models with just one execution of CV. This adaptive and computationally efficient methodology is demonstrated on a large cheminformatics data set from PubChem. Cross validated mean squared error (CVMSE) is widely used to estimate the prediction mean squared error (MSE) of statistical methods. For linear models, we show how CVMSE depends on the number of folds, v, used in cross validation, the number of observations, and the number of model parameters. We establish that the bias of CVMSE in estimating the true MSE decreases with v and increases with model complexity. In particular, the bias may be very substantial for models with many parameters relative to the number of observations, even if v is large. These results are used to correct CVMSE for its bias. We compare our proposed bias correction with that of Burman (1989), through simulated and real examples. We also illustrate that our method of correcting for the bias of CVMSE may change the results of model selection.

Thesis (MEd)--University of South Australia, 1996

Swallowing difficulties after acute stroke are common. Clinical bedside assessments are used frequently to detect acute dysphagia. Published studies which have assessed the natural history of swallowing using bedside assessments have only observed swallowing for a short period of time. The purpose of this investigation was to monitor the natural progression of dysphagic symptoms in stroke over three month using a clinical assessment. 26 patients consecutively admitted to the regional public hospital were assessed using a clinical assessment consisting of cranial nerve exam, observation of oral intake, water swallow test and inhalation cough challenge. The assessment was implemented within 72 hours post admission and then after one week, three weeks and three months. For this exploratory study, descriptive statistics were used to explore the data set. The results confirm that dysphagia after stroke is common and that there are improvements within three months.

Thesis (M.A.)--York University, 2006. Graduate Programme in Psychology. / Typescript. Includes bibliographical references (leaves 69-77). 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:MR19702

Thesis (M.S.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains vii, 66 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 55-57).

Thesis (M.S.)--Villanova University, 2007. / Psychology Dept. Includes bibliographical references.

Zugl.: Hildesheim, Univ., Diss., 2006

Lic.-avh. Uppsala Sveriges lantbruksuniversitet. / Härtill 2 uppsatser.

Thesis (Ph. D. - Nutritional Sciences)--University of Arizona, 1999. / Includes bibliographical references (leaves 154-166).