A hypothesis on improving foreign accents by optimizing variability in vocal learning brain circuits

Rapid vocal motor learning is observed when acquiring a language in early childhood, or learning to speak another language later in life. Accurate pronunciation is one of the hardest things for late learners to master and they are almost always left with a non-native accent. Here I propose a novel hypothesis that this accent could be improved by optimizing variability in vocal learning brain circuits during learning. Much of the neurobiology of human vocal motor learning has been inferred from studies on songbirds. Jarvis (2004) proposed the hypothesis that as in songbirds there are two pathways in humans: one for learning speech (the striatal vocal learning pathway), and one for production of previously learnt speech (the motor pathway). Learning new motor sequences necessary for accurate non-native pronunciation is challenging and I argue that in late learners of a foreign language the vocal learning pathway becomes inactive prematurely. The motor pathway is engaged once again and learners maintain their original native motor patterns for producing speech, resulting in speaking with a foreign accent. Further, I argue that variability in neural activity within vocal motor circuitry generates vocal variability that supports accurate non-native pronunciation. Recent theoretical and experimental work on motor learning suggests that variability in the motor movement is necessary for the development of expertise. I propose that there is little trial-by-trial variability when using the motor pathway. When using the vocal learning pathway variability gradually increases, reflecting an exploratory phase in which learners try out different ways of pronouncing words, before decreasing and stabilizing once the ‘best’ performance has been identified. The hypothesis proposed here could be tested using behavioral interventions that optimize variability and engage the vocal learning pathway for longer, with the prediction that this would allow learners to develop new motor patterns that result in more native-like pronunciation

To Examine the Effects of Exercise & Instructional Based Interventions on Executive Functioning, Motor Learning & Emotional Intelligence Abilities Among Older Adults

Motor skills are a vital part of our life, and there might be situations where we will be required to either learn a new skill or relearn a known one. We examined the effectiveness of two different interventions - eccentric exercise and motivation-based instructions on enhancing the ability of older adults to learn a novel motor skill. Exercise intervention studies have shown that as little as 12 weeks of exercise can lead to improvements in both physical fitness and cognitive function in older adults, particularly executive control. But it is still unclear whether those improvements translate to improvements in other domains that rely on executive control, like motor skill learning and emotional intelligence. Study 1 explored the effect of eccentric exercise on these domains, specifically the ability to handle proactive interference in motor learning. 22 healthy adults (65-85 years of age) were recruited and randomly assigned either to a non-exercise control group, or to an exercise intervention group that performed 12 weeks of low to moderate intensity eccentric leg exercise (Eccentron). Corresponding neurophysiological measures were also recorded using EEG. We found that the control group experienced more proactive interference from baseline learning to post-test compared to the exercise group. The latter also displayed a higher level of emotional processing abilities than controls. They provide preliminary evidence that the cognitive benefits of exercise for older adults can be extended to domains outside of but related to executive control and memory. In study 2, we examined the effectiveness of an intervention based on the OPTIMAL theory of motor learning and performance on skill acquisition in both younger and older adults. We recruited 39 younger adults and 30 older adults and randomly assigned them to either the experimental group or to the control group. The intervention affected the two groups differentially. It was somewhat successful at improving learning in the older adults, but not in the younger adults. In fact, the intervention may have interfered with learning in the latter

The role of growth, physical activity, and sport involvement on fundamental movement skills performance

Background: Fundamental Movement Skills (FMS) consist of locomotor skills that are used to propel a human body through space and object control skills that include manipulating an object in action situations. It is known that FMS are imbedded by 8 years of age, less is known about their development through adolescence. This is of particularly interest given the suggestion that during adolescence there is a perceived period of physical awkwardness. Both sports participation (SP) and habitual physical activity (PA) have been shown to improve FMS. The purpose for this study was to identify the effect growth had on FMS development, whilst controlling for PA and SP. Methods: Eighty-four individuals (23 male, 61 female) were recruited from sports camps and teams. Age, height, sitting height and weight were measured and a biological age (BA) (years from peak height velocity [PHV]) predicted. Three maturity groups were identified: pre-PHV (n=21), peri-PHV (n=12) and post-PHV (n=51). SP and PA were assessed by questionnaire. The Test of Gross Motor Development 2 (TGMD-2) was used to assess the quality of FMS performance. Mean differences between groups were tested with an ANOVA and ANCOVA. Results: Significant differences were found between BA groups and FMS scores, with post-PHV having significantly greater FMS Scores (82±6) than pre-PHV (74±6) and peri-PHV (74±11) (p0.05). A regression analysis found that sex, age, and SP (p<0.05) were significant predictors of FMS scores. Discussion: There was no observable decline in performance during rapid growth, the period of potential physical awkwardness. It was found that the most mature individuals performed the best. This is not unexpected as post-PHV participants were significantly older and therefore would have had more time to be taught, learn and practice their FMS through PA and sports participation. Interestingly, males outperformed females when adjustments were made for age and sports participation. These results do not support the contention that FMS are negatively impacted during the period of rapid adolescent growth

A comparison of working memory profiles in HIV-infected and HIV-exposed uninfected children

A thesis submitted to the Faculty of Humanities (University of the Witwatersrand, Johannesburg), in fulfillment of the requirements for the degree of Doctor of Philosophy by thesis in the field of Psychology. University of the Witwatersrand, Johannesburg, 2015Conventional psychometric measures, such as the IQ score, have significant limitations in addressing the assessment needs of linguistically and culturally diverse communities. In response, working memory assessment has been identified as a promising alternative to these constraints. It is a better predictor of scholastic success than IQ, and is essential in the acquisition of fundamental literacy and numeracy concepts in school beginners. While there is a lot of theoretical and empirical support for working memory performance in typically developing populations, less is known about its functioning in the context of atypical development; particularly in children who are infected with, or exposed to HIV in utero. This study compared the working memory (AWMA) and general neuropsychological functioning (NEPSY-II) of 273 South African school beginners (6-8 years). The sample consisted of both HIV-infected (n = 95), and HIV-exposed (n = 86) children, as well as an uninfected, unexposed typically developing control group (n = 92). Significant differences were found between the three groups on measures of working memory and general neurocognitive functioning, where the processing component of working memory appeared to be particularly impaired in the two HIV-affected atypical groups. A within-group analysis of the relative strengths and weaknesses of each of the three groups showed that both storage and processing skills in the verbal domain appeared to be general weaknesses, while visuospatial working memory was a relative strength. The former is believed to be influenced by issues of linguistic test bias in the multilingual sample, while the latter is posited to be a consequence of this very multilingualism, which affords these children an executive functioning advantage. The two HIV-affected samples also showed significant deviations in the structure of their working memory when compared to the typically developing control group. However, within-group structural comparisons of a number of working memory models showed that the four factor model comprising separate components of the verbal and visuospatial simple and processing components of working memory was still favoured, even in conditions of atypical development. The study contributes to the growing body of working memory research by presenting the working memory profiles of HIV-infected and HIV-exposed, uninfected children. It also assists in identifying HIV-exposed, uninfected children as a vulnerable and under-researched clinical group which could benefit from further intervention, as well as foregrounding working memory as a less biased alternative in the assessment of paediatric cognitive functioning.MT201

A comparison of working memory profiles in HIV-infected and HIV-exposed uninfected children

A thesis submitted to the Faculty of Humanities (University of the Witwatersrand, Johannesburg), in fulfillment of the requirements for the degree of Doctor of Philosophy by thesis in the field of Psychology. University of the Witwatersrand, Johannesburg, 2015Conventional psychometric measures, such as the IQ score, have significant limitations in addressing the assessment needs of linguistically and culturally diverse communities. In response, working memory assessment has been identified as a promising alternative to these constraints. It is a better predictor of scholastic success than IQ, and is essential in the acquisition of fundamental literacy and numeracy concepts in school beginners. While there is a lot of theoretical and empirical support for working memory performance in typically developing populations, less is known about its functioning in the context of atypical development; particularly in children who are infected with, or exposed to HIV in utero. This study compared the working memory (AWMA) and general neuropsychological functioning (NEPSY-II) of 273 South African school beginners (6-8 years). The sample consisted of both HIV-infected (n = 95), and HIV-exposed (n = 86) children, as well as an uninfected, unexposed typically developing control group (n = 92). Significant differences were found between the three groups on measures of working memory and general neurocognitive functioning, where the processing component of working memory appeared to be particularly impaired in the two HIV-affected atypical groups. A within-group analysis of the relative strengths and weaknesses of each of the three groups showed that both storage and processing skills in the verbal domain appeared to be general weaknesses, while visuospatial working memory was a relative strength. The former is believed to be influenced by issues of linguistic test bias in the multilingual sample, while the latter is posited to be a consequence of this very multilingualism, which affords these children an executive functioning advantage. The two HIV-affected samples also showed significant deviations in the structure of their working memory when compared to the typically developing control group. However, within-group structural comparisons of a number of working memory models showed that the four factor model comprising separate components of the verbal and visuospatial simple and processing components of working memory was still favoured, even in conditions of atypical development. The study contributes to the growing body of working memory research by presenting the working memory profiles of HIV-infected and HIV-exposed, uninfected children. It also assists in identifying HIV-exposed, uninfected children as a vulnerable and under-researched clinical group which could benefit from further intervention, as well as foregrounding working memory as a less biased alternative in the assessment of paediatric cognitive functioning.MT201

Normal aging in mice is associated with a global reduction in cortical spectral power and network-specific declines in functional connectivity

Normal aging is associated with a variety of neurologic changes including declines in cognition, memory, and motor activity. These declines correlate with neuronal changes in synaptic structure and function. Degradation of brain network activity and connectivity represents a likely mediator of age-related functional deterioration resulting from these neuronal changes. Human studies have demonstrated both general decreases in spontaneous cortical activity and disruption of cortical networks with aging. Current techniques used to study cerebral network activity are hampered either by limited spatial resolution (e.g. electroencephalography, EEG) or limited temporal resolution (e.g., functional magnetic resonance imaging, fMRI). Here we utilize mesoscale imaging of neuronal activity in Thy1-GCaMP6f mice to characterize neuronal network changes in aging with high spatial resolution across a wide frequency range. We show that while evoked activity is unchanged with aging, spontaneous neuronal activity decreases across a wide frequency range (0.01-4 Hz) involving all regions of the cortex. In contrast to this global reduction in cortical power, we found that aging is associated with functional connectivity (FC) deterioration of select networks including somatomotor, cingulate, and retrosplenial nodes. These changes are corroborated by reductions in homotopic FC and node degree within somatomotor and visual cortices. Finally, we found that whole-cortex delta power and delta band node degree correlate with exploratory activity in young but not aged animals. Together these data suggest that aging is associated with global declines in spontaneous cortical activity and focal deterioration of network connectivity, and that these reductions may be associated with age-related behavioral declines

Motor coordination among Greek children: from assessment to intervention

A Thesis submitted in partial fulfilment of the requirements of the University of Wolverhampton for the degree of Doctor of PhilosophyBackground: Developmental Coordination Disorder (DCD) describes children with a difficulty to acquire age-specific motor skills. Although there is a significant body of literature addressing developmental and cognitive issues in children with DCD, few studies have actually examined the associations between DCD, physical activity and physical fitness. Therefore, the aim of the present research work was to assess these associations in a series of four successive studies which were set: a) (study 1) to estimate DCD prevalence rates in Greek children and investigate whether these children exhibit different obesity and cardiorespiratory fitness levels than an overseas sample, b) (study 2) to provide evidence on the association between DCD and physical fitness levels, c) (study 3) examine whether a motor skills and exercise training intervention programme affects motor proficiency in a cohort of elementary school children with and without DCD, and d) (study 4) to test the hypothesis that DCD is associated with CVD risk, identify modes of physical activity that mediate such an association and to evaluate the CSAPPA scale as a potential tool for identifying Greek children for DCD. Methods: The total of 574 Greek (Age: 11.46 ± 1.54 years; BMI: 19.96 ± 3.53) children were assessed for anthropometry, physical fitness (flexibility, hand strength, leg explosive power, speed and cardiorespiratory fitness), motor competence (i.e., short form of the Bruininks-Oseretsky Test of Motor Profiency- BOTMP-sf) and subjected to two self assessments for: i) perception of adequacy for physical activity (CSAPPA scale), and ii) children’s participation in physical activity (Participation Questionnaire - PQ). Results: Study 1: Greek children demonstrated significantly higher DCD prevalence rates (p<0.05), higher body fat (p<0.05) and were inferior in both cardiorespiratory fitness (p<0.05) and motor competence (p<0.05) compared to an overseas sample. Study 2: Greek children with DCD demonstrated significantly higher BMI values (p<0.01) and lower leg explosive power (p<0.01), speed (p<0.01) and hand strength (p<0.01) than those without DCD. Study 3: Results showed a significant main effect of time [F(14, 115) = 3.79, p< 0.001; η2 = 0.32] for motor competence (p<0.001) between children with and without DCD. Significant main effects of group (i.e intervention and control groups) [F(42, 351) = 4.01, p< 0.001; η2 = 0.33] were observed for BMI (p<0.01), motor competence (p<0.01), cardiorespiratory fitness (p<0.01), hand strength (p<0.05), leg explosive power (p<0.05), speed (p<0.01), and free time play activities (p<0.05). Study 4: Chi-square comparisons and ANOVA, revealed significantly increased body mass (p<0.05), BMI (p<0.05) and inactivity (p<0.05), as well as significantly decreased cardiorespiratory fitness (p<0.05), motor competence (p<0.05), CSAPPA indices, and participation in free play (p<0.05) in children with DCD. Furthermore, BMI and cardiorespiratory fitness were significantly associated with motor competence (p<0.05) with inactivity as the mediating factor (p<0.05). ROC curve analyses for CSAPPA indicated an optimal cut-off at 62 points. Conclusions: 1) the relatively high DCD and obesity prevalence rates together with the low cardiorespiratory fitness suggest greater health risk for Greek children with the studied condition, 2) children with DCD tend to perform worse in selected physical fitness parameters compared to their normal peers, 3) motor skills and exercise training interventions for children with DCD may improve health and skills related fitness, and 4) inactivity mediates the relationship between DCD and CVD risk in children with DCD. Finally, the CSAPPA scale may serve as a practical and a cost-effective proxy assessment for identifying Greek children with DCD, however as this is not a standardised test for use with children, its use should be treated with caution until further validation work

The Effect of a Combined Multiple-Modality Exercise Intervention on Sensorimotor Function in Community Dwelling Older Adults, with A Subjective Cognitive Complaint: The M4 Study (Multi-Modal; Mind Motor)

Aging is associated with the increased onset of diseases such as cognitive impairment, and ultimately dementia. Participants, 55+ years, with a self-reported cognitive complaint completed a 6-month exercise intervention. They were randomized to either a multiple modality exercise program (M2), consisting of aerobic, stretching and balancing exercises or a multiple modality plus mind motor program (M4), whereby a square stepping exercise was incorporated. Participants were assessed for reaction time (RT), movement time (MT) and % errors at baseline and at 6-months using an eye tracking 1000 system. Participants performed prosaccades and antisaccades (AS). AS RT was significantly quicker from baseline – 6-months when M2 and M4 were collated p = 0.037. AS MT showed no significant difference from baseline – 6-months, p \u3e 0.05. % Errors displayed no significant changes from baseline – 6-months, p \u3e 0.05. No differences were seen between M2 and M4 groups for any of the sensorimotor outcomes examined. This study elucidates the impact of an exercise intervention on sensorimotor functioning through improvements in AS RT, however no differences were seen between groups. A multiple-modality exercise intervention can be seen to attenuate cognitive decline in older adults with a self-reported cognitive complaint

Adult Age Differences and the Role of Cognitive Resources in Perceptual-Motor Skill Acquisition: Application of a Multilevel Negative Exponential Model

The effects of advanced age and cognitive resources on the course of skill acquisition are unclear, and discrepancies among studies may reflect limitations of data analytic approaches. We applied a multilevel negative exponential model to skill acquisition data from 80 trials (four 20-trial blocks) of a pursuit rotor task administered to healthy adults (19-80 years old). The analyses conducted at the single-trial level indicated that the negative exponential function described performance well. Learning parameters correlated with measures of task-relevant cognitive resources on all blocks except the last and with age on all blocks after the second. Thus, age differences in motor skill acquisition may evolve in 2 phases: In the first, age differences are collinear with individual differences in task-relevant cognitive resources; in the second, age differences orthogonal to these resources emerg