Thesis (M.Sc.). / Written for the School of Computer Science. Title from title page of PDF (viewed 2008/05/30). Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

Thesis (Ph. D.)--University of California, San Diego, 2001. / Vita. Includes bibliographical references (leaves 122-132).

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Many learners start school at a disadvantage and stay disadvantaged. This results in an increasing number of learners needing extra support in order to benefit from schooling, obtain a qualification and become independent and part of an agile workforce. Failure to learn at school results in dependent adults with low self-esteem and low employability. Reasons for learning failure can mostly be ascribed to diversity in: socioeconomic milieu, levels of sensory stimulation and sensory integration, thinking language and learning styles. Diversity in learner needs, necessitates identifying a common denominator amongst all learners, which when stimulated results in greater learning effectiveness for all learners. Whole brain learning is a common denominator and can be defined as receiving input equally through sight, hearing and active participation, processing the sensory input simultaneously with the left and right brain while filtering perceptions through emotions for appropriate and accurate verbal or active output. Brain Gym® is claimed to be a simple and cost effective technique that stimulates whole brain learning. The aim of this research study was to scrutinise Brain Gym as a technique that promotes whole brain learning and contributes to learner success and independence. This scrutiny was approached from a Personal and Professional Leadership perspective, whose domain is (amongst others) the value of selfmastery through mental- and emotional-state management resulting in selfactualisation. A multi-layered action research strategy was followed incorporating concept analysis, a descriptive and analytical literature study, qualitative and quantitative research methods and programme development. The literature study indicated that the prevalent learning difficulties could be categorised in the following themes: language and literacy difficulties, math difficulties and difficulties in concentration and motivation. The list of difficulties Brain Gym claimed to address were narrowed down according to the themes and the following criteria: the concepts had to easily and accurately be evaluated in groups pre and post a Brain Gym intervention within a six-week time frame. Only the following concepts were evaluated: 1 Logic and gestalt brain integration 2 Crossing of the visual midline 3 Eye-hand co-ordination 4 Self image 5 Mathematical computation 6 Concentration. Developing and implementing a Brain Gym programme for a period of six weeks and evaluating the resultant changes examined causality. Quantitative data was collected by means of the Aptitude test for School Beginners and qualitative data through focus group interviews and artefacts. The qualitative data was analysed by means of descriptive and inferential statistics. The descriptive statistics regarding group distribution and tests indicated that the design was scientifically sound and presented a comparative basis for analysing the test results in terms of inferential statistics. The inferential yielded no significant results, which indicate that the Brain Gym intervention did not have a measurable effect on their ASB test scores. The quantative data was analysed by means of a descriptive narrative and presented in terms of the six concepts. Feedback from the principal educators, facilitators and the researcher indicated a noticeable improvement in all six concepts. The findings indicated that the learners have improved on a physical, emotional and social level in terms of sensory-integration, confidence, attitude, concentration and motivation. As indicated in the literature study physical, emotional and social development occurs prior to cognitive development. Due to the research period only being six weeks and thus an inadequate for measurable cognitive development, it may account for the lack of improvement on a cognitive level. It can be concluded that a Brain Gym is a technique that can stimulate the whole brain state and as such address the vast array of learning difficulties effectively in the classroom conditional to regular implementation and for a period longer than 6 weeks. Stimulating the whole brain state is the first step towards learning receptiveness and higher levels of literacy and numeracy resulting in an agile and competent workforce in South Africa. / Prof. D.P.J. Smith

An extensive mapping of the caudate-putamen in the rat for intracranial self-stimulation (ICS) sites »as undertaken to provide additional support for the role of dopamine in brain stimulation reward. Eighty-seven percent of the placements in the neostriatum supported ICS, with self-stimulation rates greater than 250/15 min at 56% of the sites. In a second experiment, animals were prepared with electrodes aimed at the lateral caudate-putamen. Those subjects displaying ICS subsequently received 6-hydroxydopamine lesions to the dopamine cell bodies in the substantia nigra pars compacta either ipsilateral or contralateral to the electrode. The destruction of the dopamine cell bodies attenuated ICS in both groups during the first post-lesion test sessions. However, the rates in the ipsilateral group declined to between 2-9% of control scores, whereas the rates in the contralateral group improved over testing to 72% of control values, 28 days after the lesion. On the basis of these data, it was concluded that unilateral destruction of the dopaminergic nigro-neostriatal (NSB) has two effects on ICS behaviour. First, unilateral reduction of neostriatal dopamine is accompanied by a loss of brain stimulation reward at sites normally innervated by the NSB, specifically the caudate-putamen. Secondly, lesions of the NSB produce a general disruption in bar pressing behaviour, as evidenced by the attenuation of ICS following contralateral lesions. The possible role of the NSB in natural reward is discussed. / Arts, Faculty of / Psychology, Department of / Graduate

INTRODUCTION: Age-related functional declines in the body and brain pose significant challenges to mobility and postural control. Older individuals are at increased risk for injury from a fall. Declines in gait and balance control make older adults more likely to suffer a fall or recurrent falls. According to the Centers for Disease Control and Prevention (CDC), falls are the leading cause of injury related death among adults age 65 years and older. (Important Facts about Falls | Home and Recreational Safety | CDC Injury Center, 2019) One out of three older adults falls annually and the likelihood of falling increases with age. (Stevens et al., 2008). In the US alone, the number of individuals living aged 65 and older is estimated at 46 million persons and is expected to reach 74 million by 2030. (Healthy Aging in Action: Advancing the National Prevention Strategy, 2019) Fall death rates in the United States increased by 30% from 2007 to 2016, and if this trend continues, it is expected that by 2030 there will be 7 deaths due to falls every hour. (Important Facts about Falls | Home and Recreational Safety | CDC Injury Center, 2019) Interventions designed to improve gait and balance control in the geriatric population can mitigate fall risk and positively impact these trends. OBJECTIVE: Gait and balance control, traditionally regarded as automatic motor processes, have since been determined to be complex motor functions reliant on executive function. (Hausdorff et al., 2005; Woollacott & Shumway-Cook, 2002) Normal walking and balance control are attentionally demanding and require shifting of attentional resources to frontal brain regions in order to maintain upright stance. This ability to dual-task is impaired in older adults. A single session of transcranial direct current stimulation (tDCS), a form of noninvasive brain stimulation, targeting the excitability of the left dorsolateral prefrontal cortex (l-dlPFC) has been found to reduce dual-task costs to gait and balance in both young and healthy older adults. (Manor et al., 2016; Zhou et al., 2014) However, little is known about how tDCS influences electroencephalogram (EEG) patterns and if changes in EEG are associated with functional outcomes. The specific aims of this study were to determine whether 1, 20-minute session tDCS targeting the l-dlPFC reduces the slow-wave/fast-wave frequency power ratio in EEG and absolute EEG power and whether these reductions are associated with changes in measures of postural control. METHODS: The data from this study was analyzed as part of a larger clinical trial testing multiple tDCS stimulation montages in combination with batteries of cognitive, gait, and balance assessments. Twenty-two older adults (median age=71 years) who were free of overt illness or disease were included in the analysis. Participants were outfitted with wireless movement sensors and a wireless 32-electrode EEG cap configured according to the 10-20 system. Participants completed a dual-task of serial subtraction by 3’s from a randomized three-digit number while standing for 60 seconds. EEG was simultaneously recorded during the 60 second trials. One, 20-minute tDCS stimulation targeting the l-dlPFC followed the balance assessment. EEG and dual-task assessments were repeated following the stimulation. EEG was not recorded simultaneously with tDCS. EEG data was processed and analyzed with Cartool EEG software. (Brunet et al., 2011) Spectral analysis of the EEG power values pre and post stimulation was conducted using a paired t-test. Power ratios of slow wave (4-8Hz) to fast wave (12-30Hz) were calculated for pre and post stimulation and analyzed for significant changes. Additionally, absolute power values in theta and beta frequency range were calculated. Postural sway velocity and postural sway area were also assessed and analyzed for changes following stimulation. RESULTS: Spectral analysis showed significant reductions in absolute power values across low theta frequency ranges following stimulation. This significant reduction in power was localized, but not exclusive, to frontal electrodes measuring activity of the l-dlPFC in the 4-8Hz frequency range. Most notably electrode F3, which has been found to correspond to the location and activity of the l-dlPFC using both the 10-20 electrode placement system and MRI guided neuronavigation. (Beam et al., 2009; De Witte et al., 2018) In addition to a significant reduction in power values, there was a reduction in slow-fast EEG ratios following stimulation. The percent reduction in EEG ratio was associated with a reduction in postural sway area (m2/s4) and sway velocity (m/s). CONCLUSION: tDCS is used to facilitate the excitability of cortical neurons. The l-dLPFC is a critical component of executive function. Due to the role of executive function in mediating attentional requirements of gait and balance, the l-dlPFC was chosen as a target to enhance dual-tasking capabilities, and thereby improve gait and postural control. The reduction in the slow wave-fast wave ratio and theta power indicates that participants had higher power in the fast wave relative to the slow wave after tDCS administration. The reduction in slow wave power may be indicative of less cognitive attentional effort required to complete a simultaneous dual-task involving postural control. This is supported by the associated reductions in postural sway following tDCS stimulation. These results further current research of tDCS as a viable intervention for improving balance and cognition in older adults and offers additional information about optimizing the efficacy of noninvasive brain stimulation to improve functional outcomes in this population.

Indiana University-Purdue University Indianapolis (IUPUI) / Non-invasive brain stimulation is valuable for studying neural circuits and treating various neurological disorders in human. However, current technologies of noninvasive brain stimulation usually have low spatial and temporal precision and poor brain penetration, which greatly limit their application. A new class of nanoparticles known as magneto-electric nanoparticles (MENs) is highly efficient in coupling an externally applied magnetics wave with generating local electric fields for neuronal activity modulation. Here, a new type of MENs was developed that consisted of CoFe2O4- BaTiO3 and had excellent magneto-electrical coupling properties. Calcium imaging technique was used to demonstrate their efficacy in evoking neuronal activity in organotyic and acute cortical slices that expressed GCaMP6 protein. For in vivo noninvasive delivery of MENs to brain, fluorescently labeled MENs were intravenously injected and attracted to pass through blood brain barrier to a targeted brain region by applying a focal magnet field. Magnetic wave (~450 G at 10 Hz) applied to mouse brain was able to activate cortical network activity, as revealed by in vivo two-photon and mesoscopic imaging of calcium signals at both cellular and global network levels. The effect was further confirmed by the increased number of c-Fos expressing cells after magnetic stimulation. Histological analysis indicated that neither brain delivery of MENs nor the subsequent magnetic stimulation caused any significant increases in the numbers of GFAP and IBA1 positive astrocytes and microglia in the brain. MENs stimulation also show high efficacy in short-term pain relieve when tested with a tibial nerve injury mouse model. The study demonstrates the feasibility of using MENs as a novel efficient and non-invasive technique of brain stimulation, which may have great potential for translation.

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