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Movement and memory are two of the most fundamental components of our existence. From the moment of birth, we rely on a variety of movements to interact with people and objects around us, and as we grow, we continuously form new motor memories to improve the fidelity of these interactions by exploring and learning more about our environment, especially in unfamiliar situations, ultimately becoming better equipped to handle novel and unknown environments. In this dissertation, we explore four facets of motor memory associated with voluntary movement and postural control in the upper limbs: (1) Optimal motor memory formation via sensorimotor integration. We ask whether the motor system combines prior memories with new sensory information to produce statistically-optimal weight estimates. We find that the weight estimate that the motor system makes in order to re-stabilize one’s arm posture when an object is rapidly removed from the hand that supports it, reflected information integration in a Bayesian, statistically-optimal fashion. Remarkably, we demonstrate that when experiencing the well-known size-weight illusion, the motor and perceptual system’s weight estimates are biased in opposite directions, suggesting two divergent modes for information integration within the central nervous system. (2) Movement features important for the learning and generalization of motor memories. We show that, velocity-dependent adaptation generalizes across different movements, even from discrete straight point-to-point to continuous circular movements, however the amount of generalization is limited and context-dependent. In a series of experiments, we quantified the contributions of different movement features to the elicited adaptation transfer. In particular, we show that other movement states (i.e. position and acceleration) make only minor contributions whereas, the contexts provided by movement geometry and movement continuity are critical. (3) Internal representation of motor memories in intrinsic-extrinsic coordinates. We show that motor memories are based not on fully intrinsic or extrinsic representations but on a gain-field (multiplicative) combination the two. This gain-field representation generalizes between actions by effectively computing movement similarity based on the Mahalanobis distance across both intrinsic and extrinsic coordinates, in line with neural recordings showing mixed intrinsic-extrinsic representations in motor and parietal cortices. (4) Motor memories with local and global generalization. We demonstrate the existence of two distinct components of motor memory displaying different generalization footprints: One generalizes only locally, around the trained movement direction and with the trained end-effector, whereas the other generalizes broadly across both., We proceed to show that broad generalization results from a rapidly-learning adaptive process, dominates on easier-to-learn tasks, and performs high-level processing, producing adaptation vectors that integrate multiple sources of information, in line with a recent theory for perceptual learning. / Engineering and Applied Sciences

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[Truncated abstract] In cricket, the bowler propels a ball using a straight arm (permitted minimal extension) in an overhead fashion to a batsman situated approximately 20m away, who attempts to strike the ball in order to score runs for their team. Cricket bowling can be generalised by two types of bowlers; fast bowlers, who primarily use high ball speed, and spin bowlers that attempt to impart spin on the ball causing it to bounce in different directions. There has been numerous studies investigating the kinematics of fast bowling in cricket, but there is a paucity of objective literature on the spin bowling action due to the complex rotations of the upper limb necessary to develop ball velocity and rotation. One primary reason is that three dimensional (3D) analysis of upper limb movement is difficult due to the high degrees of freedom and ranges of motion of the associated joints. Furthermore, existing methods do not allow measurement of the kinematics of this highly dynamic task to be performed in an ecologically sound environment. The complexity is further compounded as the upper limb does not perform regular cyclical movements like the lower limb does with gait. Therefore, this makes it difficult to determine what

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[Truncared abstract] Introduction: The assessment of any therapy requires not only an understanding of how that therapy works but also how it affects health related quality of life (HRQOL). Botulinum Toxin A(BoNT-A) therapy for upper limb spasticity management in children with hemiplegic cerebral palsy(CP) is currently under trial. Despite its use for over a decade for lower limb spasticity, little is known about the mechanisms involved in improving motor function and the effect on the child and their familys HRQOL. Both central and peripheral mechanisms are hypothesised[1]. Whilst evidence of improved quality of movement and ability to perform tasks is emerging[2-4], this cannot be directly correlated with an improvement in HRQOL. In addition, the traditional method of assessing child HRQOL by parent proxy reports has come under question[5, 6]. The World Health Organisation now recommends the collection of both parent proxy and child self-reports[7]. Aims: 1. Investigate the corticomotor projections to the upper limb in school aged children with hemiplegic CP and the changes that occur with BoNT-A therapy by transcranial magnetic stimulation (TMS). 2. Investigate the effect of upper limb BoNT-A therapy on HRQOL of school aged children with hemiplegic CP by completion of the PedsQL 4.0 Generic Core Scales and 3.0 CP Module. 3. Determine the concordance between Child Self-Report and Parent Proxy Report scores for the PedsQL 4.0 Generic Core Scales and 3.0 CP Module. 4. Determine the concordance between PedsQL scores and function as assessed by the Melbourne Assessment of Unilateral Upper Limb Function (MUUL). Methods: Design: Prospective randomised pilot study. Setting: Department of Paediatric Rehabilitation, Princess Margaret Hospital, and Centre for Neurological and Neuromuscular Disorders, Perth. Participants: 22 school aged children with hemiplegic CP aged 7yr 0mth-13yr 11mth (12 treatment, 10 control). 3 Treatment: One episode BoNT-A injections (dose 1-2U/kg/muscle) into the upper limb for treatment group. The control group received usual care. ... Conclusion: This pilot study provides preliminary evidence of the effects of upper limb BoNT-A therapy at both a central physiological and a broader quality of life level in school aged children with hemiplegic CP. At a central level, corticomotor pathway reorganisation occurs in the setting of BoNT-A. However the reorganisation is not limited to the affected side pathways suggesting a systemic BoNT-A effect or developmental changes. Similarly, in this pilot study, there was no statistically significant effect of upper limb BoNT-A on the childs HRQOL as assessed by the PedsQL although positive trends were observed 4 for a number of physical and psychosocial domains. The collection of both child self-report and parent proxy reports when assessing HRQOL is recommended, and function needs to be assessed independently. Larger studies across the broader CP population, the design of CP specific HRQOL tools appropriate for use in the higher functioning CP cohort, and alternative better tolerated methods of investigating the motor system in children with movement disorders are recommended.

The ulnar collateral ligament (UCL) is the primary restraint against valgus forces at the elbow. This structure cannot support the entire load placed upon the medial elbow during overhand throwing motions such as pitching a baseball. In this study we measured the contributions that different muscle groups make to the stability of the medial elbow, under conditions intended to reproduce the loads during pitching by varying the forearm position and loading conditions. We also evaluated the strength of the elbow musculature for the possibility of a training effect in the dominant arm of 11 male high school baseball pitchers. We collected surface EMG data in the two forearm positions to determine if the different positions used in various pitches have an effect on muscular action. We also tested an isometric and dissipative loading condition to determine if the muscles activity was load reactive. The four muscle groups tested were the flexor-pronator group (FP), the extensor-supinator group (ES), the tricep brachii (TB), and the pectoralis major (PM). We found significantly (p-value=0.001) higher peak activity levels of the flexor-pronator group in the neutral forearm position (79.4% MVIC �� 27.0% MVIC full trial peak, 30.8% MVIC �� 20.8% MVIC initial l50ms peak following activation) when compared to the supinated position (55.5% MVIC �� 29.6% MVIC full trial peak, 16.9% MVIC �� 14.8% MVIC initial l50ms peak following activation), which may explain the link between breaking pitches and medial elbow injury. We found an increase (p-value=0.001) in force output of the dominant arm (49.3 N/kg �� 12.5 N/kg) over the non-dominant arm (38.1 N/kg �� 11.0 N/kg). This finding is attributed to a training effect, which assists in protecting the elbow. These findings help provide baseline muscle activity information on protection of the medial soft tissue structures of the elbow. / Graduation date: 2004

M.Tech. (Chiropractic) / Purpose: Movement time is the time it takes an individual to perform an actual task. A faster and better movement can be invaluable in athletes using their upper limb. This study aims to see the immediate effect of a chiropractic adjustment on the segments innervating the upper limb, 05 to Ti spinal levels, to movement time in the upper limb, in athletes. Method: This study was a comparative study and consisted of two groups of fifteen. The participants were between the ages of eighteen and thirty five, with a half male to female ratio. The potential participants were examined and accepted according to the inclusion and exclusion criteria. The method of treatment administered to each participant was determined by group allocation. Group 1 received chiropractic adjustments to the segments innervating upper limb (C5-T1). Group 2 was the control group and did not receive treatment, only a rest period of ten minutes was given in between tests. Objective data findings were based on the above treatment protocols. Procedure: Treatment consisted of six treatment consultations with an additional follow up consultation over a three week period, with two consultations being performed per week interval. Objective data readings were taken at the beginning of the first, fourth and seventh consultations. Objective data was collected by the tapping task test and the movement time evaluator program. Analysis of collected data was performed by a statistician. The chiropractic adjustments used were based on restrictions identified during motion palpation and were applied on all the consultations. Results: Clinically significant results were found in group i, the treatment group. Showing a decrease in overall movement time, especially between visit i and visit 4, but also between visit 4 and visit 7. Group 2, the control group, showed a decrease in movement time before and after visit i, but this was only due to learning effect of performing the test for the second time. No statistical significance was found between visit 1 and visit 4 or visit 4 and visit 7.

Patients with cerebral palsy account for great upper extremities deviationswhile walking. However, the number of studies assessing their upper bodygait kinematics are rare and no studies have been conducted interested inthe whole body kinematics during walking. In this study, we created awhole body index, the Body Profile Score made of modified existing kinematicindexes assessing the gait pattern of children with cerebral palsy. TheBody Profile Score (BPS) is an average of combination of the Gait ProfileScore (GPS), a modified Trunk Profile Score (TPS), a modified Arm PostureScore (APS) and a also new index called Head Profile Score (HPS), basedon a similar calculation. Dierent versions of the BPS were tested on threegroups: a control group, a CP group before botulinum toxin A treatmentand a CP group after botulinum toxin A treatment. The results showed apoor level of linear correlations between the dierent BPS versions and theGait Profile Score, indicating that lower body indexes such as the GPS orGait Deviation Index (GDI) and full body index such as the BPS do not renderthe same information. The BPS is the first index proposing a full bodykinematic analysis and aims at showing that such an analysis is needed ingait assessment of spastic children in order to have a realistic overview ofthe pathological walking condition.

[Truncated abstract] This thesis consists of five experimental studies from seven data collection periods. The first two studies quantitatively analyse children with and without cerebral palsy using upper limb three dimensional (3D) motion analysis. Upper limb angular kinematics and sub-structures were measured and analysed, both of which were utilised during subsequent studies. The final three studies assess the efficacy of lycra® arm splints using clinical assessments, 3D dimensional upper limb kinematics and 3D sub-structures. Study 1 analysed 3D movement sub-structures in children with and without cerebral palsy ... The aim of the study was to quantitatively analyse movement sub-structures in children with and without cerebral palsy during four functional tasks taken from the Melbourne Assessment of Unilateral Upper Limb Function (Melbourne Assessment - Randall, Johnson & Reddihough, 1999) ... Results demonstrated significant differences in angular kinematics in children with and without cerebral palsy, while the methodology developed in this study provided improved insight into the movement of the upper limb and trunk during functional tasks. Study 3 reported a randomised controlled trial of lycra® arm splints in children with cerebral palsy across all levels of the International Classification of Functioning Disability and Health (ICF) ... Lycra® arm splints were shown to have a statistically significant impact at the level of participation, whereas no significant difference was seen at the level of impairment and activity. Study 4 reported a randomised controlled trial of the effects of lycra® arm splints on 3D movement sub-structures during functional tasks in children with cerebral palsy ... This research demonstrated that movement sub-structures (including movement time) can be quantified and are amenable to change with intervention. Study 5 reported a randomised controlled trial of the effects of lycra® arm splints on angular kinematics (thorax, shoulder and elbow) during functional tasks in children with cerebral palsy ... The benefits of the splint on angular kinematics were only apparent when worn for the 3 month period, as minimum evidence was established for the short-term (1hour) and long term (3 month post splint wear) carry-over effects.