ORCID Profile
0000-0003-0302-9426
Current Organisation
University of Tasmania
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Publisher: Elsevier BV
Date: 04-2007
DOI: 10.1016/J.BRAINRESREV.2007.01.004
Abstract: Motor overflow refers to overt involuntary movement, or covert muscle activity, that sometimes co-occurs with voluntary movement. Various clinical populations exhibit overflow. Motor overflow is also present in healthy children and the elderly, although in young adults, overt overflow is considered abnormal unless elicited under conditions of extreme force or muscle fatigue. Current theories of overflow imply that the corpus callosum may mediate production of this phenomenon. However, given that the corpus callosum is a conduit enabling the transfer of cortical information, surprisingly few studies have considered the cortical or subcortical structures underlying overflow. This review considers the developmental trend of motor overflow production, specifically in the upper-limbs, and the mechanisms thought to underlie this age-related phenomenon. Potential neurological correlates of motor overflow will be discussed in conjunction with higher order attentional processes which also regulate motor overflow production. Future research investigating the impact of attentional processes on overflow production may be particularly valuable for designing rehabilitation strategies for patients experiencing induced pathological overflow or conversely, to develop techniques to encourage the recovery of movement function in in iduals with paretic limbs.
Publisher: Informa UK Limited
Date: 05-1996
Publisher: BMJ
Date: 02-2007
Publisher: Informa UK Limited
Date: 23-02-2023
DOI: 10.1080/13607863.2022.2042188
Abstract: This study compared discussion board involvement between family carers and non-carers in the Understanding Dementia Massive Open Online Course (UD-MOOC). A mixed methods observational cohort study of family carers and non-carers was undertaken over the February-April 2020 UD-MOOC. Discussion board engagement was measured as number of posts and replies and examined longitudinally using mixed models. Discussion topics were explored through structural topic models (STM). Subsequently, thematic analysis of STM derived-topic exemplars was conducted to contextualise these discussions. Family carers were ( These results may reflect underlying motivational differences and circumstantial relevance. Perhaps the greater engagement by family carers is related to a sense of having inadequate relevant offline social resources, where engagement in the UD-MOOC discussion boards may serve as means to share experiences with others.
Publisher: Wiley
Date: 28-09-2016
DOI: 10.1002/BRB3.583
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 12-2006
Publisher: Wiley
Date: 28-09-2016
DOI: 10.1002/BRB3.582
Publisher: Informa UK Limited
Date: 05-08-2021
DOI: 10.1080/08870446.2021.1960989
Abstract: We explored which factors are associated with subjective age (SA), i.e. feeling younger, the same as, or older than one's chronological age, and whether these factors differ between men and women and between two age sub-groups. Cross-sectional study using qualitative and quantitative data for 1457 in iduals (mean age= 67.2 years). Participants reported how old they feel they are and provided comments in relation to their SA judgments. By using content analysis participants' comments were assigned to 13 categories, grouped into three higher-order categories ( In iduals reporting an older SA may benefit from interventions promoting adaptation to negative age-related changes. There is the need to eradicate negative societal views of older women.
Publisher: Elsevier BV
Date: 12-2010
Publisher: Informa UK Limited
Date: 12-04-2007
DOI: 10.1080/13825580500320681
Abstract: Previous studies on aging and attention typically examine group differences between younger and older adults, rather than seeing aging as a continuous process. Using correlational analyses, this study examined progressive changes in the magnitude of the attentional blink (AB) associated with aging. Increased age was found to be significantly associated with the ability to detect the second target (T2), whereby older age was correlated with the production of a longer and more pronounced AB this supports the proposition that aging is associated with reduced inhibitory processes and selective attention. It was also found that AB performance somewhat improves between ages 18-39 years, but tends to decline from 40 years of age onward, providing an interesting and novel finding that AB effects may become more sensitive at this point in time. The AB task may prove useful in the assessment of selective attention in normal healthy adults, as well as changes associated with pathological aging.
Publisher: JMIR Publications Inc.
Date: 18-04-2013
DOI: 10.2196/RESPROT.2372
Publisher: JMIR Publications Inc.
Date: 03-2022
DOI: 10.2196/34688
Abstract: Up to 40% of incident dementia is considered attributable to behavioral and lifestyle factors. Given the current lack of medical treatments and the projected increase in dementia prevalence, a focus on prevention through risk reduction is needed. We aim to increase dementia risk knowledge and promote changes in dementia risk behaviors at in idual and population levels. The Island Study Linking Aging and Neurodegenerative Disease (ISLAND) is a long-term prospective, web-based cohort study with nested interventions that will be conducted over a 10-year period. Target participants (n=10,000) reside in Tasmania and are aged 50 years or over. Survey data on knowledge, attitudes, and behaviors related to modifiable dementia risk factors will be collected annually. After each survey wave, participants will be provided with a personalized dementia risk profile containing guidelines for reducing risk across 9 behavioral and lifestyle domains and with opportunities to engage in educational and behavioral interventions targeting risk reduction. Survey data will be modeled longitudinally with intervention engagement indices, cognitive function indices, and blood-based biomarkers, to measure change in risk over time. In the initial 12 months (October 2019 to October 2020), 6410 participants have provided baseline data. The study is ongoing. Recruitment targets are feasible and efforts are ongoing to achieve a representative s le. Findings will inform future public health dementia risk reduction initiatives by showing whether, when, and how dementia risk can be lowered through educational and behavioral interventions, delivered in an uncontrolled real-world context. DERR1-10.2196/34688
Publisher: BMJ
Date: 22-02-2010
Abstract: The striatum and its projections are thought to be the earliest sites of Huntington's disease (HD) pathology. This study aimed to investigate progression of striatal pathology in symptomatic HD using diffusion tensor imaging. Diffusion weighted images were acquired in 18 HD patients and in 17 healthy controls twice, 1 year apart. Mean diffusivity (MD) was calculated in the caudate, putamen, thalamus and corpus callosum, and compared between groups. In addition, caudate width was measured using T1 high resolution images and correlated with caudate MD. Correlation analyses were also performed in HD between caudate utamen MD and clinical measures. MD was significantly higher in the caudate and putamen bilaterally for patients compared with controls at both time points although there were no significant MD differences in the thalamus or corpus callosum. For both groups, MD did not change significantly in any region from baseline to year 1. There was a significant negative correlation between caudate width and MD in patients at baseline but no correlation between these parameters in controls. There was also a significant negative correlation between Mini-Mental State Examination scores and caudate MD and putamen MD at both time points in HD. It appears that microstructural changes influence cognitive status in HD. Although MD was significantly higher in HD compared with controls at both time points, there were no longitudinal changes in either group. This finding does not rule out the possibility that MD could be a sensitive biomarker for detecting early change in preclinical HD.
Publisher: Elsevier BV
Date: 03-2009
DOI: 10.1016/J.BANDC.2008.09.005
Abstract: Motor overflow refers to involuntary movement or muscle activity that may coincide with voluntary movement. This study examined factors influencing motor overflow in 17 children (8-11 years), and 17 adults (18-35 years). Participants performed a finger pressing task by exerting either 33% or 66% of their maximal force output using their dominant or non-dominant hand. Attention was manipulated by tactile stimulation to one or both hands. Overflow relative to the target force was greater in children compared to adults, and at the lower target force for both groups, but was not influenced by attentional stimulation. Childhood overflow was greater when the left-hand performed the task. Although an immature motor system may underlie an inability to suppress involuntary movement, childhood overflow may provide motor stabilization.
Publisher: SAGE Publications
Date: 06-2003
DOI: 10.1177/108705470300600402
Abstract: The stop signal task (stop task) is designed to assess inhibitory control and is a frequently used research tool in clinical disorders such as ADHD and schizophrenia. Previous methods of setting stop signal delay and of assessing inhibitory control are problematic. The current study reports two modifications that improve the task as a measure of inhibitory control. The first modification was to set stop signal delays proportional to go mean reaction time (go MRT) to better account for inter-subject variability in go MRT. Twenty-eight normal children were tested, and all standard, stop task dependent measures were obtained when delays were set by this method. The second modification was to calculate a novel dependent measure called the area of inhibition (AOI) which provides a more complete measure of inhibitory control than the slope of the relative finishing time z-scores (ZRFT-slope). Implications for the assessment of inhibitory control in clinical populations are discussed.
Publisher: Informa UK Limited
Date: 2009
DOI: 10.1080/15622970802562793
Abstract: Investigation of neurological soft signs (NSSs) in schizophrenia may allow for a greater understanding of its underlying pathology. Motor overflow, involuntary movement occurring during voluntary movement, is a NSS thought to occur to a greater degree in schizophrenia. The aim of the current study was to replicate the only objective investigation which found enhanced motor overflow in schizophrenia and to further characterise its properties in a more systematic manner than previous research. The current study involved examining motor overflow production in 30 participants (15 with schizophrenia, 15 controls). Participants exerted 25 and 75% of their maximal force output, while overflow was monitored in the passive hand using linear variable differential transformer (LVDT) units. Patients with schizophrenia not only exhibited a significantly greater degree of motor overflow, compared to controls, they also exhibited a differential pattern of overflow production. Direct investigation of the cortical processes leading to motor overflow may provide a more complete understanding of the pathological relevance of motor overflow, and by extension NSSs, in schizophrenia.
Publisher: Oxford University Press (OUP)
Date: 02-1999
Publisher: Elsevier BV
Date: 02-2004
Publisher: Informa UK Limited
Date: 12-03-2007
DOI: 10.1080/13803390600657693
Abstract: Research in preclinical mutation carriers for Huntington's disease (HD) aims to find measures sensitive to preclinical decline. This study investigated attentional abilities in mutation carriers and noncarriers. Mutation carriers demonstrated a normal "attentional blink" during rapid serial visual presentation, normal covert visual orienting, and normal directing of attention to tactile stimuli. However, they were more likely than noncarriers to make anticipatory responses before target presentation. Additionally, those closer to estimated onset of HD demonstrated larger "inhibition of return" effects. The findings suggest potential changes in cognitive inhibition of unwanted responses, and in automatic inhibition of visual orienting, in preclinical HD.
Publisher: Elsevier BV
Date: 11-2017
DOI: 10.1016/J.BIOPSYCH.2017.03.022
Abstract: Attention-deficit/hyperactivity disorder (ADHD) symptoms are most commonly treated with stimulant medication such as methylphenidate (MPH) however, approximately 25% of patients show little or no symptomatic response. We examined the extent to which initial changes in brain functional connectivity (FC) associated with the first MPH dose in boys newly diagnosed with ADHD predict MPH-associated changes in ADHD inattentiveness and hyperactivity symptoms at 3 months. Brain FC was estimated using steady-state visual evoked potential partial coherence before and 90 minutes after the administration of the first MPH dose to 40 stimulant drug-naïve boys newly diagnosed with ADHD while they performed the AX version of the continuous performance task. The change in parent-rated inattention and hyperactivity scores over the first 3 months of MPH medication was correlated with the initial 90-minute MPH-mediated FC changes. Hyperactivity improvements at 3 months were associated with first-dose MPH-mediated FC reductions restricted to frontal-prefrontal sites following the appearance of the "A" and at frontal and right temporal sites during the appearance of the "X." Corresponding 3-month inattention score improvement was associated with initial MPH-mediated FC reductions restricted to occipitoparietal sites following the appearance of the "A." These findings are discussed in the context of MPH effects on the default mode network and the possible role of the default mode network in MPH-mediated improvements in inattention and hyperactivity symptom scores.
Publisher: Cambridge University Press (CUP)
Date: 11-2005
DOI: 10.1017/S1355617705051003
Abstract: This study utilised a finger force task to investigate the influence of attention and age on the occurrence of motor overflow in the form of mirror movements in neurologically intact adults. Forty right-handed participants were recruited from three age groups: 20-30 years, 40-50 years, and 60-70 years. Participants were required to maintain a target force using both their index and middle fingers, representing 50% of their maximum strength capacity for that hand. Attention was directed to a hand by activating a bone conduction vibrator attached to the small finger of that hand. Based on Cabeza's (2002) model of hemispheric asymmetry reduction in older adults, it was hypothesised that mirror movements would increase with age. Furthermore, it was expected that when the attentional demands of the task were increased, motor overflow occurrence would be exacerbated for the older adult group. The results obtained provide support for the model, and qualified support for the hypothesis that increasing the attentional demands of a task results in greater motor overflow. It is proposed that the association between mirror movements and age observed in this study may result from an age-related increase in bihemispheric activation that occurs in older adults, who, unlike younger adults, benefit from bihemispheric processing for task performance.
Publisher: SAGE Publications
Date: 02-2009
DOI: 10.1080/17470210802269217
Abstract: This study investigated the influence of attentional and motor demands on motor overflow in 17 healthy young (18–35 years) and 17 older adults (60–80 years). Participants performed a finger pressing task by exerting either 33% or 66% of their maximal force output using their dominant or nondominant hand. Overflow was concurrently recorded in the passive hand. Attention was manipulated via a tactile stimulus presented to one or both hands for certain trials. Results showed that older adults exhibited greater overflow than young adults and that the effect of target force was exacerbated in older adults. Further, only older adult overflow was increased when tactile stimulation was directed to one or both hands. Increased overflow in older adults may result from bilateral cortical activation that is influenced by increased task demands. To perform comparatively to younger adults, older adults may compensate for age-related brain changes by recruiting an increased cortical network.
Publisher: Informa UK Limited
Date: 03-2018
DOI: 10.2147/NDT.S158308
Publisher: Public Library of Science (PLoS)
Date: 04-05-2022
DOI: 10.1371/JOURNAL.PONE.0267205
Abstract: Dementia is a global public health priority and risk reduction is an important pillar of the public health response. While 40% of cases are estimated to be attributable to modifiable health and lifestyle risk factors, public awareness of the evidence is low, limiting peoples’ opportunity to adopt risk-reducing behaviours. To address this gap, we designed, implemented, and evaluated an educational intervention, the Preventing Dementia Massive Open Online Course (PDMOOC). This mixed-methods study examined the reach and impact of the free and globally available PDMOOC, to assess its potential to provide effective dementia risk reduction education to a broad international audience. Over 100,000 in iduals participated in the PDMOOC across seven iterations from 2016 to 2020, with 55,739 of these consenting to participate in research. Their mean age was 49 years (SD = 15), they came from 167 different countries, and the majority were female (86%), had completed post-secondary education (77%), lived in high-income countries (93%) and worked in health care and social assistance (63%). This demographic profile changed across time, with more men, people with higher education and people from low- and middle-income countries participating in recent course iterations. Two-thirds of participants completed the PDMOOC completion was associated with being aged 50 to 70 years, residing in a high-income country, having tertiary education, and working in the health sector. Participants reported high levels of satisfaction with the PDMOOC, improved dementia risk reduction understanding and self-efficacy, increased motivation to maintain healthy lifestyles, and, importantly, application of their learning to health behaviour change with the potential to reduce their dementia risk. The PDMOOC educated a large global audience about dementia risk reduction, which contributed to participants making risk-reducing behaviour changes. This suggests MOOCs can be a successful public health strategy to improve dementia risk reduction understanding.
Publisher: JMIR Publications Inc.
Date: 04-11-2021
Abstract: p to 40% of incident dementia is considered attributable to behavioral and lifestyle factors. Given the current lack of medical treatments and the projected increase in dementia prevalence, a focus on prevention through risk reduction is needed. e aim to increase dementia risk knowledge and promote changes in dementia risk behaviors at in idual and population levels. he Island Study Linking Aging and Neurodegenerative Disease (ISLAND) is a long-term prospective, web-based cohort study with nested interventions that will be conducted over a 10-year period. Target participants (n=10,000) reside in Tasmania and are aged 50 years or over. Survey data on knowledge, attitudes, and behaviors related to modifiable dementia risk factors will be collected annually. After each survey wave, participants will be provided with a personalized dementia risk profile containing guidelines for reducing risk across 9 behavioral and lifestyle domains and with opportunities to engage in educational and behavioral interventions targeting risk reduction. Survey data will be modeled longitudinally with intervention engagement indices, cognitive function indices, and blood-based biomarkers, to measure change in risk over time. n the initial 12 months (October 2019 to October 2020), 6410 participants have provided baseline data. The study is ongoing. ecruitment targets are feasible and efforts are ongoing to achieve a representative s le. Findings will inform future public health dementia risk reduction initiatives by showing whether, when, and how dementia risk can be lowered through educational and behavioral interventions, delivered in an uncontrolled real-world context. ERR1-10.2196/34688
Publisher: American Medical Association (AMA)
Date: 12-1998
DOI: 10.1001/ARCHPSYC.55.12.1105
Abstract: Symptoms of attention-deficit/hyperactivity disorder (ADHD) have been associated with frontal lobe deficits. We used a novel brain electrical imaging method to investigate rapid and continuous changes in brain activity during the continuous performance task (CPT) in normal boys and in boys with ADHD. The litude and latency topography of the steady-state visually evoked potential (SSVEP) were examined while subjects performed the "X" version of the CPT (CPT-X the reference task) and the "A-X" version of the CPT (CPT-AX). Seventeen boys meeting DSM-III-R criteria for ADHD and 17 age-matched controls participated in the study. Brain electrical activity was recorded from 64 scalp sites. During the reference task, subjects pressed a microswitch on the unpredictable appearance of the letter X. During the CPT-AX, subjects were required to press the microswitch on the appearance of the letter X only if an A had preceded it. In the interval between the appearances of the A and the X of the correct trials of the CPT-AX, control boys showed transient reductions in SSVEP latency at right prefrontal sites. By contrast, boys with ADHD showed no change or an increase in prefrontal SSVEP latency at right prefrontal sites. Our results suggest increased speed of prefrontal neural processing in children without ADHD following a priming stimulus, and a deficit in such processes in children with ADHD.
Publisher: Wiley
Date: 17-04-2023
DOI: 10.1002/HPJA.602
Abstract: Encouraging people to adopt life‐long habits that reduce dementia risk is necessary to manage the growing global prevalence of this condition and is, therefore, a global health priority. Current initiatives promoting risk‐reducing behaviour primarily attract participants from a limited range of backgrounds, even if widely available. This may inadvertently increase health inequities, as the people who are most likely to develop dementia are the people who are least involved in risk‐reduction initiatives. Interpersonal communication can effectively disseminate health messages to demographically erse populations and may, therefore, broaden the reach of dementia risk‐reduction information. Coding reliability thematic analysis was used to categorise reports of information sharing provided by participants from one global online dementia risk education initiative, the Preventing Dementia Massive Open Online Course, or MOOC. These reports of information sharing were provided in response to the feedback question: “If you have already applied your MOOC learning, please tell us how.” Information was reportedly shared with a wide range of people, including those from demographic groups that are under‐represented among Preventing Dementia MOOC participants. Information about specific risk factors was shared, along with general information about the course and/or dementia risk reduction. Some participants also reported that the people they shared information with were initiating risk‐reducing behaviours. Interpersonal communication has the potential to disseminate dementia risk reduction information to, and promote behaviour change among, a broad group of people at risk of dementia, thereby increasing equity in dementia risk education.
Publisher: Springer Science and Business Media LLC
Date: 25-10-2017
DOI: 10.1038/S41598-017-14020-9
Abstract: Alzheimer’s Disease (AD) is the most common form of dementia, characterised by extracellular amyloid deposition as plaques and intracellular neurofibrillary tangles of tau protein. As no current clinical test can diagnose in iduals at risk of developing AD, the aim of this project is to evaluate a blood-based biomarker panel to identify in iduals who carry this risk. We analysed the levels of 22 biomarkers in clinically classified healthy controls (HC), mild cognitive impairment (MCI) and Alzheimer’s participants from the well characterised Australian Imaging, Biomarker and Lifestyle (AIBL) study of aging. High levels of IL-10 and IL-12/23p40 were significantly associated with amyloid deposition in HC, suggesting that these two biomarkers might be used to detect at risk in iduals. Additionally, other biomarkers (Eotaxin-3, Leptin, PYY) exhibited altered levels in AD participants possessing the APOE ε4 allele. This suggests that the physiology of some potential biomarkers may be altered in AD due to the APOE ε4 allele, a major risk factor for AD. Taken together, these data highlight several potential biomarkers that can be used in a blood-based panel to allow earlier identification of in iduals at risk of developing AD and/or early stage AD for which current therapies may be more beneficial.
Publisher: JMIR Publications Inc.
Date: 05-08-2022
Abstract: emory strategy training for older adults helps maintain and improve cognitive health but is traditionally offered face-to-face, which is resource intensive, limits accessibility, and is challenging during a pandemic. Web-based interventions, such as the Online Personalised Training in Memory Strategies for Everyday (OPTIMiSE) program, may overcome such barriers. e report on OPTIMiSE’s feasibility, acceptability, and efficacy. ustralians aged ≥60 years reporting subjective cognitive decline participated in this single-arm pre-post web-based intervention. OPTIMiSE is a 6-module web-based program offered over 8-weeks with a 3-month booster. It has a problem-solving approach to memory issues, focusing on psychoeducation about memory and aging, knowledge and practice of compensatory memory strategies, and personalized content related to in idual priorities. We examined the feasibility (recruitment, attrition, and data collection), acceptability (recommendation to others, suggestions for improvement, and withdrawal reasons), and efficacy (change in goal satisfaction, strategy knowledge and use, self-reported memory, memory satisfaction and knowledge, and mood thematic content analysis of the most significant change and the application of knowledge and strategies in daily life) of OPTIMiSE. PTIMiSE was feasible, demonstrated by strong interest (633 in iduals screened), a satisfactory level of attrition (158/312, 50.6%), and minimal missing data from those completing the intervention. It was acceptable, with 97.4% (150/154) of participants agreeing they would recommend OPTIMiSE, the main suggestion for improvement being more time to complete modules, and withdrawal reasons similar to those in in-person interventions. OPTIMiSE was also efficacious, with linear mixed-effects analyses revealing improvements, of moderate to large effect sizes, across all primary outcomes (all i P /i & .001): memory goal satisfaction (Cohen i d /i after course=1.24 Cohen i d /i at 3-month booster=1.64), strategy knowledge (Cohen i d /i after course=0.67 Cohen i d /i at 3-month booster=0.72) and use (Cohen i d /i after course=0.79 Cohen i d /i at 3-month booster=0.90), self-reported memory (Cohen i d /i after course=0.80 Cohen i d /i at 3-month booster=0.83), memory satisfaction (Cohen i d /i after course=1.25 Cohen i d /i at 3-month booster=1.29) and knowledge (Cohen i d /i after course=0.96 Cohen i d /i at 3-month booster=0.26), and mood (Cohen i d /i after course=−0.35 nonsignificant Cohen i d /i at booster). Furthermore, the most significant changes reported by participants ( i strategy use, improvements in daily life, reduced concern about memory /i , i confidence and self-efficacy /i , and i sharing and shame busting with others /i ) reflected the course objectives and were consistent with themes arising from previous in-person interventions. At the 3-month booster, many participants reported continued implementation of knowledge and strategies in their daily lives. his feasible, acceptable, and efficacious web-based program has the potential to enable access to evidence-based memory interventions for older adults worldwide. Notably, the changes in knowledge, beliefs, and strategy use continued beyond the initial program. This is particularly important for supporting the growing number of older adults living with cognitive concerns. ustralian New Zealand Clinical Trials Registry ACTRN12620000979954 4cdantv R2-10.3233/ADR-200251
Publisher: JMIR Publications Inc.
Date: 07-12-2021
DOI: 10.2196/21681
Abstract: Massive open online course (MOOC) research is an emerging field to date, most research in this area has focused on participant engagement. The aim of this study is to evaluate both participant engagement and measures of satisfaction, appropriateness, and burden for a MOOC entitled Understanding Multiple Sclerosis (MS) among a cohort of 3518 international course participants. We assessed the association of key outcomes with participant education level, MS status, caregiver status, sex, and age using summary statistics, and 2-tailed t tests, and chi-square tests. Of the 3518 study participants, 928 (26.37%) were people living with MS. Among the 2590 participants not living with MS, 862 (33.28%) identified as formal or informal caregivers. Our key findings were as follows: the course completion rate among study participants was 67.17% (2363/3518) the course was well received, with 96.97% (1502/1549) of participants satisfied, with an appropriate pitch and low burden (a mean of 2.2 hours engagement per week) people living with MS were less likely than those not living with MS to complete the course and people with a recent diagnosis of MS, caregivers, and participants without a university education were more likely to apply the material by course completion. The Understanding MS MOOC is fit for purpose it presents information in a way that is readily understood by course participants and is applicable in their lives.
Publisher: Elsevier BV
Date: 12-2006
DOI: 10.1016/J.BRAINRES.2006.09.070
Abstract: While research suggests that normal ageing is associated with compromised ided attentional processing abilities, such studies are comparatively few in comparison to other areas of attention (e.g. selective attention). The current study sought to examine age-related effects in ided attention using a global/local paradigm in three normal healthy age groups: younger adults (20-40 years), middle-aged (40-60 years), and older adults (61-80 years). In three experiments we sought to examine the ability to process local/global stimuli, ability to ide and switch attention, as well as the influence of a cue on target performance. Experiment 1 revealed global precedence and interference for all age groups older adults were overall significantly slower in their response times. Experiments 2 and 3 suggest an age-related impairment in iding and switching attention, which may begin as early as middle age. The findings are considered to reflect reduced inhibitory mechanisms, as well as possible neurobiological changes in the normal ageing process.
Publisher: JMIR Publications Inc.
Date: 20-04-2023
DOI: 10.2196/41712
Abstract: Memory strategy training for older adults helps maintain and improve cognitive health but is traditionally offered face-to-face, which is resource intensive, limits accessibility, and is challenging during a pandemic. Web-based interventions, such as the Online Personalised Training in Memory Strategies for Everyday (OPTIMiSE) program, may overcome such barriers. We report on OPTIMiSE’s feasibility, acceptability, and efficacy. Australians aged ≥60 years reporting subjective cognitive decline participated in this single-arm pre-post web-based intervention. OPTIMiSE is a 6-module web-based program offered over 8-weeks with a 3-month booster. It has a problem-solving approach to memory issues, focusing on psychoeducation about memory and aging, knowledge and practice of compensatory memory strategies, and personalized content related to in idual priorities. We examined the feasibility (recruitment, attrition, and data collection), acceptability (recommendation to others, suggestions for improvement, and withdrawal reasons), and efficacy (change in goal satisfaction, strategy knowledge and use, self-reported memory, memory satisfaction and knowledge, and mood thematic content analysis of the most significant change and the application of knowledge and strategies in daily life) of OPTIMiSE. OPTIMiSE was feasible, demonstrated by strong interest (633 in iduals screened), a satisfactory level of attrition (158/312, 50.6%), and minimal missing data from those completing the intervention. It was acceptable, with 97.4% (150/154) of participants agreeing they would recommend OPTIMiSE, the main suggestion for improvement being more time to complete modules, and withdrawal reasons similar to those in in-person interventions. OPTIMiSE was also efficacious, with linear mixed-effects analyses revealing improvements, of moderate to large effect sizes, across all primary outcomes (all P .001): memory goal satisfaction (Cohen d after course=1.24 Cohen d at 3-month booster=1.64), strategy knowledge (Cohen d after course=0.67 Cohen d at 3-month booster=0.72) and use (Cohen d after course=0.79 Cohen d at 3-month booster=0.90), self-reported memory (Cohen d after course=0.80 Cohen d at 3-month booster=0.83), memory satisfaction (Cohen d after course=1.25 Cohen d at 3-month booster=1.29) and knowledge (Cohen d after course=0.96 Cohen d at 3-month booster=0.26), and mood (Cohen d after course=−0.35 nonsignificant Cohen d at booster). Furthermore, the most significant changes reported by participants (strategy use, improvements in daily life, reduced concern about memory, confidence and self-efficacy, and sharing and shame busting with others) reflected the course objectives and were consistent with themes arising from previous in-person interventions. At the 3-month booster, many participants reported continued implementation of knowledge and strategies in their daily lives. This feasible, acceptable, and efficacious web-based program has the potential to enable access to evidence-based memory interventions for older adults worldwide. Notably, the changes in knowledge, beliefs, and strategy use continued beyond the initial program. This is particularly important for supporting the growing number of older adults living with cognitive concerns. Australian New Zealand Clinical Trials Registry ACTRN12620000979954 4cdantv RR2-10.3233/ADR-200251
Publisher: BMJ
Date: 21-01-2020
DOI: 10.1136/PRACTNEUROL-2019-002335
Abstract: Ageing, genetic, medical and lifestyle factors contribute to the risk of Alzheimer’s disease and other dementias. Around a third of dementia cases are attributable to modifiable risk factors such as physical inactivity, smoking and hypertension. With the rising prevalence and lack of neuroprotective drugs, there is renewed focus on dementia prevention strategies across the lifespan. Neurologists encounter many people with risk factors for dementia and are frequently asked whether lifestyle changes may help. Exercise has emerged as a key intervention for influencing cognition positively, including reducing the risk of age-related cognitive decline and dementia. This article focuses on the current evidence for physical inactivity as a modifiable dementia risk factor and aims to support neurologists when discussing risk reduction.
Publisher: JMIR Publications Inc.
Date: 22-12-2014
DOI: 10.2196/MENTAL.3654
Abstract: Encouraging middle-aged adults to maintain their physical and cognitive health may have a significant impact on reducing the prevalence of dementia in the future. Mobile phone apps and interactive websites may be one effective way to target this age group. However, to date there has been little research investigating the user experience of dementia risk reduction tools delivered in this way. The aim of this study was to explore participant engagement and evaluations of three different targeted smartphone and Web-based dementia risk reduction tools following a four-week intervention. Participants completed a Web-based screening questionnaire to collect eligibility information. Eligible participants were asked to complete a Web-based baseline questionnaire and were then randomly assigned to use one of the three dementia risk reduction tools for a period of four weeks: (1) a mobile phone application (2) an information-based website and (3) an interactive website. User evaluations were obtained via a Web-based follow-up questionnaire after completion of the intervention. Of 415 eligible participants, 370 (89.16%) completed the baseline questionnaire and were assigned to an intervention group 200 (54.05%) completed the post-intervention questionnaire. The average age of participants was 52 years, and 149 (75%) were female. Findings indicated that participants from all three intervention groups reported a generally positive impression of the tools across a range of domains. Participants using the information-based website reported higher ratings of their overall impression of the tool, F2,191=4.12, P=.02 how interesting the information was, F2,189=3.53, P=.03 how helpful the information was, F2,192=4.15, P=.02 and how much they learned, F2,188=3.86, P=.02. Group differences were significant between the mobile phone app and information-based website users, but not between the interactive website users and the other two groups. Additionally, participants using the information-based website reported significantly higher scores on their ratings of the ease of navigation, F2,190=4.20, P=.02, than those using the mobile phone app and the interactive website. There were no significant differences between groups on ratings of ease of understanding the information, F2,188=0.27, P=.76. Most participants from each of the three intervention groups indicated that they intended to keep using the dementia risk reduction eHealth tool. Overall, results indicated that while participants across all three intervention groups reported a generally positive experience with the targeted dementia risk reduction tools, participants using the information-based website provided a more favorable evaluation across a range of areas than participants using the mobile phone app. Further research is required to investigate whether targeted dementia risk reduction tools, in the form of interactive websites and mobile apps, can be improved to provide benefits above those gained by providing static information alone.
Publisher: Springer Science and Business Media LLC
Date: 19-11-2015
DOI: 10.1186/S13195-015-0157-7
Abstract: Cerebrospinal fluid (CSF) biomarkers, although of established utility in the diagnostic evaluation of Alzheimer’s disease (AD), are known to be sensitive to variation based on pre-analytical s le processing. We assessed whether gravity droplet collection versus syringe aspiration was another factor influencing CSF biomarker analyte concentrations and reproducibility. Standardized lumbar puncture using small calibre atraumatic spinal needles and CSF collection using gravity fed collection followed by syringe aspirated extraction was performed in a s le of elderly in iduals participating in a large long-term observational research trial. Analyte assay concentrations were compared. For the 44 total paired s les of gravity collection and aspiration, reproducibility was high for biomarker CSF analyte assay concentrations (concordance correlation [95%CI]: beta-amyloid1-42 (Aβ42) 0.83 [0.71 - 0.90]), t-tau 0.99 [0.98 - 0.99], and phosphorylated tau (p-tau) 0.82 [95 % CI 0.71 - 0.89]) and Bonferroni corrected paired s le t-tests showed no significant differences (group means (SD): Aβ42 366.5 (86.8) vs 354.3 (82.6), p = 0.10 t-tau 83.9 (46.6) vs 84.7 (47.4) p = 0.49 p-tau 43.5 (22.8) vs 40.0 (17.7), p = 0.05). The mean duration of collection was 10.9 minutes for gravity collection and minute for aspiration. Our results demonstrate that aspiration of CSF is comparable to gravity droplet collection for AD biomarker analyses but could considerably accelerate throughput and improve the procedural tolerability for assessment of CSF biomarkers.
Publisher: Bentham Science Publishers Ltd.
Date: 12-2001
Abstract: Current theories of dopaminergic and noradrenergic mechanisms, which are thought to be of importance in the regulation of attention are reviewed. A biphasic model of dopaminergic function is described, in which tonic dopamine exerts a suppressive influence on subcortical dopamine systems by altering tonic hasic dopaminergic relationships. Noradrenergic mechanisms are of importance in modulating sensory processing at the prefrontal cortical level. The work of Silberstein and colleagues utilizing Steady-State Visually Evoked Potential, during the course of an A-X Continuous Performance Task enables examination of the spatial distribution and dynamics of electrical brain activity during the task. The maintenance of activation in the interval between A and X provides a measure of working memory, thought to be related to prefrontal-parietal activation, which is facilitated by administration of methylphenidate to children with ADHD, suggesting that working memory may be a core deficiency in children with ADHD. While tonic dopamine activity in ventral striatum/accumbens gates inhibitory activity, dorsolateral prefrontal-parietal connections allow maintenance of working memory required for goal completion.
Publisher: Informa UK Limited
Date: 02-01-2023
Publisher: BMJ
Date: 06-2004
Abstract: We investigated both motor overflow and ability to control voluntary movement in patients with Huntington's disease (HD). We hypothesised that, compared with controls, overflow would be significantly greater in HD participants and that they would exhibit poorer control of voluntary movement. In a finger flexion task, participants had to maintain target forces representing 25, 50, or 75% of the maximum strength capacity for whichever finger was performing the task overflow was measured in the corresponding finger of the non-responding hand. HD participants exhibited significantly greater motor overflow than controls, and more difficulty controlling the target force with the active hand. In addition, the degree of overflow in HD participants positively correlated with overall UHDRS motor symptom severity. The presence of exacerbated motor overflow in HD, and its correlation with symptom severity, is an important finding worthy of further investigation.
Publisher: Elsevier BV
Date: 03-2017
DOI: 10.1016/J.JAGP.2016.11.008
Abstract: To review the efficacy of a home-based four-session in idualized face-to-face cognitive rehabilitation (MAXCOG) intervention for clients with mild cognitive impairment (MCI) or early dementia and their close supporters. Randomized controlled trial comparing the intervention group (MAXCOG) with treatment as usual (control). A total of 55 client-supporter dyads were enrolled in the study and 40 completed 25 client-supporter dyads completed MAXCOG and 15 completed treatment as usual. Both MAXCOG and control groups included more MCI cases than dementia (22 versus 3 and 12 versus 3, respectively). Four weekly in idual sessions of MAXCOG consisting of personalized interventions to address in idually relevant goals, supported by the provision of the MAXCOG information resource. The primary outcomes were goal performance and satisfaction, assessed using the Canadian Occupational Performance Measure (COPM). Questionnaires assessing mood, illness adjustment, quality of life, and carer burden were also administered. The intervention group displayed significantly higher performance and satisfaction with primary goals on the COPM post-intervention than the control group, using a per-protocol analysis. The MAXCOG intervention is effective in improving goal performance and satisfaction in clients with MCI and early dementia.
Publisher: Elsevier BV
Date: 2007
DOI: 10.1016/J.NEUROPSYCHOLOGIA.2006.12.023
Abstract: Cognitive deficits in Huntington's disease (HD) have been attributed to neuronal degeneration within the striatum however, postmortem and structural imaging studies have revealed more widespread morphological changes. To examine the impact of HD-related changes in regions outside the striatum, we used functional magnetic resonance imaging (fMRI) in HD to examine brain activation patterns using a Simon task that required a button press response to either congruent or incongruent arrow stimuli. Twenty mild to moderate stage HD patients and 17 healthy controls were scanned using a 3T GE scanner. Data analysis involved the use of statistical parametric mapping software with a random effects analysis model to investigate group differences brain activation patterns compared to baseline. HD patients recruited frontal and parietal cortical regions to perform the task, and also showed significantly greater activation, compared to controls, in the caudal anterior cingulate, insula, inferior parietal lobules, superior temporal gyrus bilaterally, right inferior frontal gyrus, right precuneus/superior parietal lobule, left precentral gyrus, and left dorsal premotor cortex. The significantly increased activation in anterior cingulate-frontal-motor-parietal cortex in HD may represent a primary dysfunction due to direct cell loss or damage in cortical regions, and/or a secondary compensatory mechanism of increased cortical recruitment due to primary striatal deficits.
Publisher: University of Illinois Press
Date: 07-2013
DOI: 10.5406/AMERJPSYC.126.2.0227
Abstract: Motor overflow is overt involuntary movement that accompanies voluntary movement. This study investigated the change in overflow production across a timed trial and the factors that affected this profile. Seventeen children (aged 8-11 years), 17 young adults (aged 18-35 years), and 17 older adults (aged 60-80 years) performed a 5-s finger pressing task by exerting 33% or 66% of their maximal force output using either index finger. Overflow was recorded as force from the alternative index finger. Young adult overflow remained stable over the 5 s. The rate of overflow increase over time was significantly greater for children than young adults. There was also a tendency for a greater overflow increase in older adults than in young adults. This overflow gradient was also greater in the right hand, particularly for children. These findings indicate that the neurological processes underlying overflow production are age dependent. Overflow progressed in a dynamic fashion over the course of a trial in children and older adults, probably because of increased bilateral cortical activation and the facilitation of motor task performance. This study is unique in quantitatively capturing the dynamic profile of overflow production in healthy participants across the life span.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 03-2012
Publisher: JMIR Publications Inc.
Date: 23-06-2020
Abstract: assive open online course (MOOC) research is an emerging field to date, most research in this area has focused on participant engagement. he aim of this study is to evaluate both participant engagement and measures of satisfaction, appropriateness, and burden for a MOOC entitled Understanding Multiple Sclerosis (MS) among a cohort of 3518 international course participants. e assessed the association of key outcomes with participant education level, MS status, caregiver status, sex, and age using summary statistics, and 2-tailed i t /i tests, and chi-square tests. f the 3518 study participants, 928 (26.37%) were people living with MS. Among the 2590 participants not living with MS, 862 (33.28%) identified as formal or informal caregivers. Our key findings were as follows: the course completion rate among study participants was 67.17% (2363/3518) the course was well received, with 96.97% (1502/1549) of participants satisfied, with an appropriate pitch and low burden (a mean of 2.2 hours engagement per week) people living with MS were less likely than those not living with MS to complete the course and people with a recent diagnosis of MS, caregivers, and participants without a university education were more likely to apply the material by course completion. he Understanding MS MOOC is fit for purpose it presents information in a way that is readily understood by course participants and is applicable in their lives.
Publisher: Informa UK Limited
Date: 05-2011
DOI: 10.1080/00222895.2011.561376
Abstract: Motor overflow is involuntary overt movement or covert muscle activity that cooccurs with voluntary movement. Overflow is present in several pathological conditions, as well as in neurologically healthy children and older adults, and can be induced in healthy young adults under effortful conditions. This motor phenomenon may provide insight into the underlying mechanisms and kinetic characteristics of voluntary and involuntary motor control in various populations. Although often measured behaviorally using force transduction techniques, different methods of calculating and presenting such overflow data have resulted in seemingly contradictory findings, with limited discussion of the advantages and limitations of different approaches. In this article, the authors examined the relevant literature to highlight significant methodological considerations for authors and readers conducting or appraising this type of research. Issues regarding the interpretation and reporting of findings are also discussed. Researchers are encouraged to continue using behavioral measures to create well-defined variables that enable the study of the kinematic characteristics of overflow, as these may offer promising new ways forward in better characterizing and understanding this intriguing movement phenomenon.
Start Date: 2016
End Date: 2017
Funder: Dementia Collaborative Research Centre
View Funded Activity