The effect of Sailuotong (SLT) on neurocognitive and cardiovascular function in healthy adults: a randomised, double-blind, placebo controlled crossover pilot trial

Background: Sailuotong (SLT) is a standardised herbal medicine formula consisting of Panax ginseng, Ginkgo biloba, and Crocus sativus, and has been designed to enhance cognitive and cardiovascular function. Methods: Using a randomised, double-blind, placebo controlled crossover design, this pilot study assessed the effect of treatment for 1 week with SLT and placebo (1 week washout period) on neurocognitive and cardiovascular function in healthy adults. Sixteen adults completed a computerised neuropsychological test battery (Compass), and had their electroencephalographic (EEG) activity and cardiovascular system function assessed. Primary outcome measures were cognitive test scores and oddball task event-related potential (ERP) component amplitudes. Secondary outcome measures were resting EEG spectral band amplitudes, and cardiovascular parameters. Results: Treatment with SLT, compared to placebo, resulted in small improvements in working memory, a slight increase in auditory target (cf. nontarget) P3a amplitude, and a decrease in auditory N1 target (cf. nontarget) amplitude. There was no effect of SLT on EEG amplitude in delta, theta, alpha, or beta bands in both eyes open and eyes closed resting conditions, or on aortic and peripheral pulse pressure, and resting heartrate. Conclusions: Findings suggest that SLT has the potential to improve working memory performance in healthy adults; a larger sample size is needed to confirm this. Trial registration: Australia New Zealand Clinical Trials Registry Trial Registration Id: ACTRN12610000947000

The effect of Sailuotong (SLT) on neurocognitive and cardiovascular function in healthy adults: a randomised, double-blind, placebo controlled crossover pilot trial

Background: Sailuotong (SLT) is a standardised herbal medicine formula consisting of Panax ginseng, Ginkgo biloba, and Crocus sativus, and has been designed to enhance cognitive and cardiovascular function. Methods: Using a randomised, double-blind, placebo controlled crossover design, this pilot study assessed the effect of treatment for 1 week with SLT and placebo (1 week washout period) on neurocognitive and cardiovascular function in healthy adults. Sixteen adults completed a computerised neuropsychological test battery (Compass), and had their electroencephalographic (EEG) activity and cardiovascular system function assessed. Primary outcome measures were cognitive test scores and oddball task event-related potential (ERP) component amplitudes. Secondary outcome measures were resting EEG spectral band amplitudes, and cardiovascular parameters. Results: Treatment with SLT, compared to placebo, resulted in small improvements in working memory, a slight increase in auditory target (cf. nontarget) P3a amplitude, and a decrease in auditory N1 target (cf. nontarget) amplitude. There was no effect of SLT on EEG amplitude in delta, theta, alpha, or beta bands in both eyes open and eyes closed resting conditions, or on aortic and peripheral pulse pressure, and resting heartrate. Conclusions: Findings suggest that SLT has the potential to improve working memory performance in healthy adults; a larger sample size is needed to confirm this. Trial registration: Australia New Zealand Clinical Trials Registry Trial Registration Id: ACTRN12610000947000

A randomised controlled trial investigating the effects of Mediterranean diet and aerobic exercise on cognition in cognitively healthy older people living independently within aged care facilities: The Lifestyle Intervention in Independent Living Aged Car

Background: The rapid ageing of the population is becoming an area of great concern, both globally and in Australia. On a societal level, the cost of supporting an ageing demographic, particularly with their associated medical requirements, is becoming an ever increasing burden that is only predicted to rise in the foreseeable future. The progressive decline in individuals\u27 cognitive ability as they age, particularly with respect to the ever increasing incidence of Alzheimer\u27s Disease (AD) and other cognitive complications, is in many respects one of the foundation stones of these concerns. There have been numerous observational studies reporting on the positive effects that aerobic exercise and the Mediterranean diet appear to have on improving cognitive ability. However, the ability of such interventions to improve cognitive ability, or even reduce the rate of cognitive ageing, has not been fully examined by substantial interventional studies within an ageing population. Methods: The LIILAC trial will investigate the potential for cognitive change in a cohort of cognitively healthy individuals, between the ages of 60 and 90 years, living in independent accommodation within Australian aged care facilities. This four-arm trial will investigate the cognitive changes which may occur as a result of the introduction of aerobic exercise and/or Mediterranean diet into individuals\u27 lifestyles, as well as the mechanisms by which these changes may be occurring. Participants will be tested at baseline and 6 months on a battery of computer based cognitive assessments, together with cardiovascular and blood biomarker assessments. The cardiovascular measures will assess changes in arterial stiffness and central pulse pressures, while the blood measures will examine changes in metabolic profiles, including brain derived neurotrophic factor (BDNF), inflammatory factors and insulin sensitivity. Conclusion: It is hypothesised that exercise and Mediterranean diet interventions, both individually and in combination, will result in improvements in cognitive performance compared with controls. Positive findings in this research will have potential implications for the management of aged care, particularly in respect to reducing the rate of cognitive decline and the associated impacts both on the individual and the broader community

Magnetic resonance imaging for assessment of cerebrovascular reactivity and its relationship to cognition: a systematic review

BACKGROUND: Cerebrovascular reactivity (CVR) refers to the responsiveness of cerebral vasculature to vasoactive stimuli. CVR is an indicator of brain health and can be assessed using vasodilatory techniques and magnetic resonance imaging (MRI). Using such approaches, some researchers have explored the relationship between CVR and cognition; here we systematically review this work. RESULTS: We extracted information pertaining to: (1) study location and design, participant characteristics, sample sizes, (2) design of vascular challenge, end-tidal CO 2 (etCO 2 ) concentrations (if applicable), (3) MRI protocol, (4) cognitive assessment, (5) CVR values, and outcomes of statistical analyses with cognitive tests. Five studies assessed participants with cognitive impairment compared to controls, one studied patients with multiple sclerosis with or without cognitive impairment compared to controls, one examined patients with moyamoya disease with or without cognitive impairment, two investigated patients with Type 2 diabetes mellitus (T2DM), and one was a cross-sectional study with younger and older healthy adults. Cognition was typically probed using the MMSE and tests of executive function, while a number of vasodilatory techniques were employed. CONCLUSION: CVR was associated with cognition in six of ten studies, but heterogeneity of study samples, designs and vasodilatory methods may have a role in the inconsistent findings. We make recommendations for future research that includes use of a multi-domain cognitive assessment and standardised hypercapnic challenge with MRI

Multi-Sensor PHD: Construction and Implementation by Space Partitioning

International audienceThe Probability Hypothesis Density (PHD) is a well-known method for single-sensor multi-target tracking problems in a Bayesian framework, but the extension to the multi-sensor case seems to remain a challenge. In this paper, an extension of Mahler's work to the multi-sensor case provides an expression of the true PHD multi-sensor data update equation. Then, based on the configuration of the sensors' fields of view (FOVs), a joint partitioning of both the sensors and the state space provides an equivalent yet more practical expression of the data update equation, allowing a more effective implementation in specific FOV configurations

An investigation of cerebral oxygen utilization, blood flow and cognition in healthy aging

BACKGROUND: Understanding how vascular and metabolic factors impact on cognitive function is essential to develop efficient therapies to prevent and treat cognitive losses in older age. Cerebral metabolic rate of oxygen (CMRO2), cerebral blood flow (CBF) and venous oxygenation (Yv) comprise key physiologic processes that maintain optimum functioning of neural activity. Changes to these parameters across the lifespan may precede neurodegeneration and contribute to age-related cognitive decline. This study examined differences in blood flow and metabolism between 31 healthy younger (<50 years) and 29 healthy older (>50 years) adults; and investigated whether these parameters contribute to cognitive performance. METHOD: Participants underwent a cognitive assessment and MRI scan. Grey matter CMRO2 was calculated from measures of CBF (phase contrast MRI), arterial and venous oxygenation (TRUST MRI) to assess group differences in physiological function and the contribution of these parameters to cognition. RESULTS: Performance on memory (p<0.001) and attention tasks (p<0.001) and total CBF were reduced (p<0.05), and Yv trended toward a decrease (p = .06) in the older group, while grey matter CBF and CMRO2 did not differ between the age groups. Attention was negatively associated with CBF when adjusted (p<0.05) in the older adults, but not in the younger group. There was no such relationship with memory. Neither cognitive measure was associated with oxygen metabolism or venous oxygenation in either age group. CONCLUSION: Findings indicated an age-related imbalance between oxygen delivery, consumption and demand, evidenced by a decreased supply of oxygen with unchanged metabolism resulting in increased oxygen extraction. CBF predicted attention when the age-effect was controlled, suggesting a task- specific CBF- cognition relationship

Regional cerebrovascular reactivity and cognitive performance in healthy aging

Cerebrovascular reactivity (CVR) reflects the response of brain blood vessels to vasoactive stimuli, such as neural activity. The current research assessed age-related changes in regional CVR to 5% CO2 inhalation in younger (n = 30, range: 21-45 years) and older (n = 29, range: 55-75 years) adults, and the contribution of regional CVR to cognitive performance using blood-oxygen-level dependent contrast imaging (BOLD) functional magnetic resonance imaging (fMRI) at 3T field strength. CVR was measured by inducing hypercapnia using a block-design paradigm under physiological monitoring. Memory and attention were assessed with a comprehensive computerized aging battery. MRI data analysis was conducted using MATLAB® and SPM12. Memory and attention performance was positively associated with CVR in the temporal cortices. Temporal lobe CVR influenced memory performance independently of age, gender, and education level. When analyzing age groups separately, CVR in the hippocampus contributed significantly to memory score in the older group and was also related to subjective memory complaints. No associations between CVR and cognition were observed in younger adults. Vascular responsiveness in the brain has consequences for cognition in cognitively healthy people. These findings may inform other areas of research concerned with vaso-protective approaches for prevention or treatment of neurocognitive decline

The Cognitive Ageing, Nutrition and Neurogenesis trial: Design and progress

Introduction: Cohort studies indicate that long-chain n-3 polyunsaturated fatty acids and flavonoids may improve cognition and reduce dementia risk. The neuroprotective effects of these dietary components indicate that they are likely to be additive and potentially synergistic. Methods: The Cognitive Ageing, Nutrition and Neurogenesis trial hypothesizes that an intervention comprising long-chain n-3 polyunsaturated fatty acids (docosahexaenoic acid and eicosapentaenoic acid) and cocoa flavan-3-ols (n-3 FLAV) will mitigate the cognitive decline anticipated to naturally occur over 1 year in older adults with mild cognitive impairment or subjective memory impairment. A double-blinded, placebo-controlled parallel design is used. Two hundred fifty-nine adults (aged ≥55 years) with mild cognitive impairment or subjective memory impairment were recruited and randomized to a control or n-3 FLAV group (1.5 g docosahexaenoic acid + eicosapentaenoic acid and 500 mg n-3 FLAV daily) for 12 months. Cognitive performance was measured three times over the 1-year intervention, at 0 (baseline), 3, and 12 months. The primary end point is hippocampus-sensitive cognitive function (e.g., number of false-positives on the Picture Recognition Task of the Cognitive Drug Research test battery). Secondary outcomes include additional cognitive measures, brain atrophy and blood flow (assessed by magnetic resonance imaging), vascular function, circulating biomarkers of cardiovascular and cognitive health, gut microflora speciation and metabolism, red blood cell fatty acid status, and urine flavan-3-ol metabolites. The intervention arms were matched for sex and apolipoprotein E4 status to allow retrospective exploratory analysis of the impact of these variables on response to intervention.  Results: Screening began in 2015, with all baseline visits completed in March 2017. The intervention was finished in March 2018.  Discussion: Cognitive Ageing, Nutrition and Neurogenesis aims to identify an effective diet-based intervention to prevent or delay cognitive impairment in cognitively at-risk individuals, which could ultimately contribute to a reduced population burden of dementia