Now showing 1 - 10 of 36
  • Publication
    Metadata only
    Clinical determinants of dual tasking in people with premanifest Huntington disease
    (2021)
    Reyes, Alvaro
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    Bartlett, Danielle
    ;
    Rankin, Timothy J.
    ;
    Zaenker, Pauline
    ;
    Turner, Kate
    ;
    ;
    Fu, Shih Ching
    ;
    Domingos, Josefa
    ;
    Georgiou-Karistianis, Nellie
    ;
    Ziman, Mel
    ;
    Cruickshank, Travis

    Objective. Dual-tasking deficiencies are common in people with Huntington disease (HD) and contribute to reduced functional independence. To date, few studies have investigated the determinants of dual-tasking deficiencies in this population. The reliability of dual-tasking measures has also been poorly investigated in HD. The purpose of this study was to investigate the influence of clinical determinants on dual-tasking performance and to determine the association of disease burden outcomes on dual-tasking performance in individuals with premanifest HD.

    Methods. Thirty-six individuals with premanifest HD and 28 age-and sex-matched healthy controls were recruited for this study. Participants performed 3 single-task (2 cognitive and 1 motor) and 2 dual-task assessments, comprising motor (postural stability) and cognitive (simple or complex mental arithmetic) components. In addition, participants performed a comprehensive clinical battery comprising motor, cognitive, mood, and sleep assessments as well as lifestyle and disease burden measures.

    Results. Poorer sleep quality was associated with greater cognitive dual-task cost in individuals with premanifest HD. Compared with healthy controls, people with premanifest HD demonstrated an impaired capacity to dual task. Dual-task measures exhibited acceptable test–retest reliability in premanifest HD and healthy control groups.

    Conclusion. These results show that dual-tasking measures are sensitive and reliable in individuals with premanifest HD. Furthermore, poor sleep quality is associated with worse cognitive performance on dual tasks, which should be considered by rehabilitation specialists when examining and therapeutically managing dual-tasking problems in individuals with HD and other neurodegenerative populations in the future.

    Impact. This study adds important knowledge to the sparse literature on dual-tasking deficiencies in people with HD. When examining and therapeutically managing dual-tasking problems in this and other neurodegenerative populations, rehabilitation specialists should consider that people with premanifest HD may have an impaired capacity to dual task. Clinicians also should assess sleep quality, as poorer sleep quality is associated with worse cognitive performance on dual tasks in these individuals.

    Lay Summary. If you have premanifest HD and poor quality of sleep, you may pay more attention to maintaining postural stability rather than performing arithmetic calculations to reduce the risk of falling

    WOS© Citations 2Scopus© Citations 2  37
  • Publication
    Metadata only
    Is neuroimaging ready for the classroom? A systematic review of hyperscanning studies in learning
    (Elsevier, 2023)
    Tan, Jessica Sok Hui
    ;
    Wong, Jin Nen
    ;
    Whether education research can be informed by findings from neuroscience studies has been hotly debated since Bruer's (1997) famous claim that neuroscience and education are “a bridge too far”. However, this claim came before recent advancements in portable electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) technologies, and second-person neuroscience techniques that brought about significant headway in understanding instructor-learner interactions in the classroom. To explore whether neuroscience and education are still two very separate fields, we systematically review 15 hyperscanning studies that were conducted in real-world classrooms or that implemented a teaching-learning task to investigate instructor-learner dynamics. Findings from this investigation illustrate that inter-brain synchrony between instructor and learner is an additional and valuable dimension to understand the complex web of instructor- and learner-related variables that influence learning. Importantly, these findings demonstrate the possibility of conducting real-world classroom studies with portable neuroimaging techniques and highlight the potential of such studies in providing translatable real-world implications. Once thought of as incompatible, a successful coupling between neuroscience and education is now within sight.
    WOS© Citations 2  17Scopus© Citations 5
  • Publication
    Open Access
    Acute effects of high-intensity aerobic exercise on motor cortical excitability and inhibition in sedentary adults
    (2022)
    Hendy, Ashlee
    ;
    Andrushko, Justin W.
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    Della Gatta, Paul A.
    ;
    Transcranial magnetic stimulation studies have demonstrated increased cortical facilitation and reduced inhibition following aerobic exercise, even when examining motor regions separate to the exercised muscle group. These changes in brain physiology following exercise may create favorable conditions for adaptive plasticity and motor learning. One candidate mechanism behind these benefits is the increase in brain-derived neurotropic factor (BDNF) observed following exercise, which can be quantified from a venous blood draw. The aim of this study was to investigate changes in motor cortex excitability and inhibition of the upper limb, and circulating BDNF, following high-intensity interval training (HIIT) on a stationary bicycle. Nineteen sedentary adults participated in a randomized crossover design study involving a single bout of high-intensity interval cycling for 20 min or seated rest. Venous blood samples were collected, and transcranial magnetic stimulation (TMS) was used to stimulate the extensor carpi radialis (ECR), where motor evoked potentials (MEP) were recorded pre- and post-condition. Following exercise, there was a significant increase (29.1%, p < 0.001) in corticospinal excitability measured at 120% of resting motor threshold (RMT) and a reduction in short-interval cortical inhibition (SICI quantified as 86.2% increase in the SICI ratio, p = 0.002). There was a non-significant (p = 0.125) 23.6% increase in BDNF levels. Collectively, these results reflect a net reduction in gamma aminobutyric acid (GABA)ergic synaptic transmission and increased glutamatergic facilitation, resulting in increased corticospinal excitability. This study supports the notion that acute high-intensity exercise provides a potent stimulus for inducing cortical neuroplasticity, which may support enhanced motor learning.
    WOS© Citations 5  61  45Scopus© Citations 5
  • Publication
    Open Access
    I think therefore I learn
    (National Institute of Education (Singapore), 2021) ;
      75  130
  • Publication
    Open Access
    Strength and conditioning programmes for improving back muscle fatigability in firefighters
    (2022) ;
    Kan, Tommy Yew Weng
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    Hostler, David
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    ;
    Roslan Abdul Ghani Mohamed Jamil
    Back pain and back-related injuries are common in firefighters. The purpose of this study was to compare the effectiveness of two different types of strength and conditioning programmes in improving back muscle fatigability in firefighters. A total of 12 male firefighters completed 16 weeks on supervised exercise intervention programme. The Functional Group was prescribed unilateral movements that mimicked the asymmetrical nature of firefighting tasks. The Conventional Group performed more bilaterally loaded, symmetrical exercise training. The lumbar extensor muscles’ resistance to fatigue was assessed using the Modified Sorensen test with electromyography (EMG). The EMG median frequency slope was less steep (p = 0.023, η²p =0.420) after training, indicating improvement in fatigability. There was no difference between the groups (p = .605, η²p = 0.028) and no interaction effect (p = 0.245, η²p =0.132). In conclusion, a well-rounded strength and conditioning programme is promising in improving back muscle fatigability in firefighters.
      102  76
  • Publication
    Metadata only
    Inhibition, excitation and bilateral transfer following a unilateral complex finger-tapping task in young and older adults
    (2021)
    Nuzum, Nathan
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    ;
    Macpherson, Helen
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    Loughman, Amy
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    Szymlek-Gay, Ewa A.
    ;
    Hendy, Ashlee
    Neuroplasticity underpins motor learning, with abnormal neuroplasticity related to age-associated motor declines. Bilateral transfer of motor learning, through rehabilitation, may mitigate these declines; however, the magnitude of transfer may be reduced in older populations. This study investigated excitatory and inhibitory pathways in the trained and untrained hemispheres following unilateral training of a complex finger-tapping task across ageing. Fifteen young (26.2 ± 3.8 years) and 11 older adults (63.7 ± 15.4 years) received transcranial magnetic stimulation, although surface electromyography was recorded from the extensor digitorum communis (EDC) and abductor pollicis brevis (APB), before and after practicing a complex finger-tapping task with the dominant hand. Excitability, inhibition (expressed as percent change scores from pre- to post-training), motor task performance and bilateral transfer were assessed between groups. Investigation of hemispheric differences within each group was completed for measures that significantly differed between groups. There were no between-group differences in task performance or bilateral transfer, with task performance improving post-training irrespective of group for both hands (p < 0.05). Pre- to post-inhibition change scores of the untrained EDC muscle increased (p = 0.034) in older compared with younger adults, indicating reduced inhibition in older adults. Inhibition change scores significantly differed between hemispheres for the young group only (p = 0.037). Only the younger group presented with hemispheric lateralisation, providing some support for the Hemispheric Asymmetry Reduction in OLDer adults (HAROLD) hypothesis. Whether this reduction is evidence of de-differentiation or compensation will need to be confirmed with additional measures.
    WOS© Citations 3  199Scopus© Citations 3
  • Publication
    Open Access
    Altered prefrontal cortex responses in older adults with subjective memory complaints and dementia during dual-task gait: An fNIRS study
    (2020) ;
    Rantalainen, Timo
    ;
    Nuzum, Nathan
    ;
    Valente, Leah
    ;
    Macpherson, Helen
    People with cognitive impairments show deficits during physical performances such as gait, in particular during cognitively challenging conditions (i.e. dual‐task gait [DTG]). However, it is unclear if people at risk of dementia, such as those with subjective memory complaints (SMC), also display gait and central deficits associated with DTG. In this study, we investigated the effects of single‐ and dual‐task gait (STG and DTG), on left prefrontal cortex (PFC) activation in elderly people with subjective memory complaints (SMC) and Dementia. A total of 58 older adults (aged 65–94 years; 26 Healthy; 23 SMC; 9 Dementia) were recruited. Gait spatiotemporal characteristics (i.e. stride velocity and length) were assessed using an instrumented walkway during STG and DTG. Single‐channel functional near‐infrared spectroscopy over the left PFC was used to measure changes in oxyhaemoglobin (O2Hb) during gait. Stride velocity and length during STG (all p < .05) and DTG (all p < .000) were significantly impaired in people with Dementia compared to Healthy and SMC individuals. No differences were observed between Healthy and SMC. For STG, a greater increase in O2Hb (p < .05) was observed in those with Dementia compared to the Healthy and SMC, while no differences were observed between Healthy and SMC. A significant increase and decline in O2Hb was observed during DTG in the SMC and Dementia groups, respectively, compared to Healthy. Our findings indicate an altered pattern of cerebral haemodynamic response of the left PFC in DTG in people with SMC and Dementia, which may suggest that central changes precede functional impairments in people with SMC.
    WOS© Citations 10Scopus© Citations 9  275  43
  • Publication
    Metadata only
    Differences in the gut microbiome across typical ageing and in Parkinson's disease
    (2023)
    Nuzum, Nathan
    ;
    Szymlek-Gay, Ewa A.
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    Loke, Stella
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    Dawson, Samantha L.
    ;
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    Hendy, Ashlee
    ;
    Loughman, Amy
    ;
    Macpherson, Helen
    The microbiota-gut-brain axis' role in Parkinson's disease (PD) pathophysiology, and how this differs from typical ageing, is poorly understood. Presently, gut-bacterial diversity, taxonomic abundance and metabolic bacterial pathways were compared across healthy young (n = 22, 18–35 years), healthy older (n = 33, 50–80 years), and PD groups (n = 18, 50–80 years) using shotgun sequencing and compositional data analysis. Associations between the gut-microbiome and PD symptoms, and between lifestyle factors (fibre intake, physical activity, and sleep) and the gut-microbiome were conducted. Alpha-diversity did not differ between PD participants and older adults, whilst beta-diversity differed between these groups. Lower abundance of Butyricimonas synergistica, a butyrate-producer, was associated with worse PD non-motor symptoms in the PD group. Regarding typical ageing, Bifidobacterium bifidum, was greater in the younger compared to older group, with no difference between the older and PD group. Abundance of metabolic pathways related to butyrate production did not differ among the groups, while other metabolic pathways differed among the three groups. Sleep efficiency was positively associated with Roseburia inulinivorans in the older group. These results highlight the relevance of gut-microbiota to PD and that reduced butyrate-production may be involved with PD pathophysiology. Future studies should account for lifestyle factors when investigating gut-microbiomes across ageing and in PD.
    WOS© Citations 3  40Scopus© Citations 3
  • Publication
    Metadata only
    Development of a Parkinson’s disease specific falls questionnaire
    (2021)
    Harris, Dale M.
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    Duckham, Rachel L.
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    Daly, Robin M.
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    Abbott, Gavin
    ;
    Johnson, Liam
    ;
    Rantalainen, Timo
    ;
    Background: Falls are a major health burden for older adults with Parkinson's disease (PD), but there is currently no reliable questionnaire to capture the circumstances and consequences of falls in older adults with PD. This study aimed to develop a PD-specific falls questionnaire and to evaluate its test-retest reliability in older adults with PD.

    Methods: A novel PD-specific falls questionnaire (PDF-Q) was developed in two modes (online and paper-based version) and used to assess falls and near-falls events over the past 12-months. Questions were agreed upon by an expert group, with the domains based on previous falls-related questionnaires. The questions included the number and circumstances (activities, location and direction) of falls and near-falls, and consequences (injuries and medical treatment) of falls. The PDF-Q was distributed to 46 older adults with PD (online n = 30, paper n = 16), who completed the questionnaire twice, 4 weeks apart. Kappa (κ) statistics were used to establish test-retest reliability of the questionnaire items.

    Results: Pooled results from both questionnaires for all participants were used to assess the overall test-retest reliability of the questionnaire. Questions assessing the number of falls (κ = 0.41) and the number of near-falls (κ = 0.51) in the previous 12-months demonstrated weak agreement, while questions on the location of falls (κ = 0.89) and near-falls (κ = 1.0) demonstrated strong to almost perfect agreement. Questions on the number of indoor (κ = 0.86) and outdoor (κ = 0.75) falls demonstrated moderate to strong agreement, though questions related to the number of indoor (κ = 0.47) and outdoor (κ = 0.56) near-falls demonstrated weak agreement. Moderate to strong agreement scores were observed for the most recent fall and near-fall in terms of the direction (indoor fall κ = 0.80; outdoor fall κ = 0.81; near-fall κ = 0.54), activity (indoor fall κ = 0.70; outdoor fall κ = 0.82; near-fall κ = 0.65) and cause (indoor fall κ = 0.75; outdoor fall κ = 0.62; near-fall κ = 0.56).

    Conclusions: The new PDF-Q developed in this study was found to be reliable for capturing the circumstances and consequences of recent falls and near-falls in older adults with PD.

    WOS© Citations 4Scopus© Citations 5  12