Preparing Malaysia for Population Aging through the Advanced Memory and Cognitive Service in Hospital Universiti Sains Malaysia.

Improving healthcare and living conditions has led to an increase in life expectancies and challenges of population aging in Malaysia. The Advanced Memory and Cognitive Service builds on integrated healthcare among multidisciplinary specialists to provide holistic and patient-centred healthcare. The service treats older adults experiencing neurocognitive impairment as well as young individuals with complex neurocognitive disorders and thoroughly screens asymptomatic individuals at high risk of developing neurocognitive disorders. This early intervention strategy is a preventive effort in the hope of reducing disease burden and improving quality of life to prepare Malaysia for the forthcoming population aging.

Harmonized-Multinational qEEG norms (HarMNqEEG).

This paper extends frequency domain quantitative electroencephalography (qEEG) methods pursuing higher sensitivity to detect Brain Developmental Disorders. Prior qEEG work lacked integration of cross-spectral information omitting important functional connectivity descriptors. Lack of geographical diversity precluded accounting for site-specific variance, increasing qEEG nuisance variance. We ameliorate these weaknesses. (i) Create lifespan Riemannian multinational qEEG norms for cross-spectral tensors. These norms result from the HarMNqEEG project fostered by the Global Brain Consortium. We calculate the norms with data from 9 countries, 12 devices, and 14 studies, including 1564 subjects. Instead of raw data, only anonymized metadata and EEG cross-spectral tensors were shared. After visual and automatic quality control, developmental equations for the mean and standard deviation of qEEG traditional and Riemannian DPs were calculated using additive mixed-effects models. We demonstrate qEEG "batch effects" and provide methods to calculate harmonized z-scores. (ii) We also show that harmonized Riemannian norms produce z-scores with increased diagnostic accuracy predicting brain dysfunction produced by malnutrition in the first year of life and detecting COVID induced brain dysfunction. (iii) We offer open code and data to calculate different individual z-scores from the HarMNqEEG dataset. These results contribute to developing bias-free, low-cost neuroimaging technologies applicable in various health settings.

The roles of caffeine and corticosteroids in modulating cortical excitability after paired associative stimulation (PAS) and transcranial alternating current stimulation (tACS) in caffeine-naïve and caffeine-adapted subjects.

The modulatory effects of non-invasive brain stimulation (NIBS) are highly variable between subjects. This variability may be due to uncontrolled caffeine consumption and circadian rhythms. Therefore, here we studied if caffeine consumption, systemically available caffeine measured in saliva, and daytime have effects on the excitability and plasticity of the motor cortex. Since both, time of the day and caffeine may mediate their effects via cortisol, we also quantified corticosteroids in saliva. Experiment 1 was performed in caffeine-naïve participants (n = 30) and compared the effects of PAS or tACS with different stimulation intensities on the motor cortex with or without caffeine 200 mg administered in a double-blind fashion. Experiment 2 was performed in regular caffeine consumers (n = 30) and compared the influence of time of day on the effects of tACS (true or sham) on the motor cortex also with or without caffeine administered in a double-blind fashion. Caffeine increased the saliva corticosteroid concentrations in both experimental groups, and corticosteroid concentrations were higher in the morning in caffeine consumers. Gender also affected corticosteroid concentrations. There was a positive correlation between caffeine concentrations and baseline cortical excitability in caffeine-adapted participants, and a negative correlation between poststimulation caffeine concentrations and motor evoked potential (MEP) amplitudes after sham stimulation in caffeine-naïve subjects. No correlations were found between poststimulation caffeine or corticosteroid concentrations, and plasticity aftereffects. PAS and tACS did not elicit changes in the corticosteroid concentrations. We conclude that moderate caffeine consumption alters cortical excitability but not plasticity aftereffects. This study was registered in the ClinicalTrials.gov with these registration IDs: 1) NCT03720665 https://clinicaltrials.gov/ct2/results?cond=NCT03720665&term=&cntry=&state=&city=&dist= 2) NCT04011670 https://clinicaltrials.gov/ct2/results?cond=&term=NCT04011670&cntry=&state=&city=&dist=.

Confounding effects of caffeine on neuroplasticity induced by transcranial alternating current stimulation and paired associative stimulation.

OBJECTIVE: We examined the effects of caffeine, time of day, and alertness fluctuation on plasticity effects after transcranial alternating current stimulation (tACS) or 25 ms paired associative stimulation (PAS25) in caffeine-naïve and caffeine-adapted subjects. METHODS: In two randomised, double-blinded, cross-over or placebo-controlled (caffeine) studies, we measured sixty subjects in eight sessions (n = 30, Male: Female = 1:1 in each study). RESULTS: We found caffeine increased motor cortex excitability in caffeine naïve subjects. The aftereffects in caffeine naïve subjects were enhanced and prolonged when combined with PAS 25. Caffeine also increased alertness and the motor evoked potentials (MEPs) were reduced under light deprivation in caffeine consumers both with and without caffeine. In caffeine consumers, the time of day had no effect on tACS-induced plasticity. CONCLUSIONS: We conclude that caffeine should be avoided or controlled as confounding factor for brain stimulation protocols. It is also important to keep the brightness constant in all sessions and study groups should not be mixed with caffeine-naïve and caffeine consuming participants. SIGNIFICANCE: Caffeine is one of the confounding factors in the plasticity induction studies and it induces different excitability effects in caffeine-naïve and caffeine-adapted subjects. This study was registered in the ClinicalTrials.gov with these registration IDs: 1) NCT03720665 https://clinicaltrials.gov/ct2/results?cond=NCT03720665&term=&cntry=&state=&city=&dist= 2) NCT04011670 https://clinicaltrials.gov/ct2/results?cond=&term=NCT04011670&cntry=&state=&city=&dist=.