Research suggests that white noise may facilitate auditory working memory performance via stochastic resonance. Stochastic resonance is quantified by plotting cognitive performance as a function of noise intensity. The plot would appear as an inverted U-curve, that is, a moderate noise is beneficial for performance whereas too low and too much noise attenuates performance. However, knowledge about the optimal signal-to-noise ratio (SNR) needed for stochastic resonance to occur in the brain, particularly in the neural network of auditory working memory, is limited and demand further investigation. In the present study, we extended previous works on the impact of white noise on auditory working memory performance by including multiple background noise levels to map out the inverted U-curve for the stochastic resonance. Using functional magnetic resonance imaging (fMRI), twenty healthy young adults performed a word-based backward recall span task under four signal-to-noise ratio conditions: 15, 10, 5, and 0-dB SNR. Group results show significant behavioral improvement and increased activation in frontal cortices, primary auditory cortices, and anterior cingulate cortex in all noise conditions, except at 0-dB SNR, which decreases activation and performance. When plotted as a function of signal-to-noise ratio, behavioral and fMRI data exhibited a noise-benefit inverted U-shaped curve. Additionally, a significant positive correlation was found between the activity of the right superior frontal gyrus (SFG) and performance in 5-dB SNR. The predicted phenomenon of SR on auditory working memory performance is confirmed. Findings from this study suggest that the optimal signal-to-noise ratio to enhance auditory working memory performance is within 10 to 5-dB SNR and that the right SFG may be a strategic structure involved in enhancement of auditory working memory performance.

Background: Resting-state functional magnetic resonance imaging (rs-fMRI) can evaluate brain functional connectivity without requiring subjects to perform a specific task. This rs-fMRI is very useful in patients with cognitive decline or unable to respond to tasks. However, long scan durations have been suggested to measure connectivity between brain areas to produce more reliable results, which are not clinically optimal. Therefore, this study aims to evaluate a shorter scan duration and compare the scan duration of 10 and 15 min using the rs-fMRI approach. Methods: Twenty-one healthy male and female participants (seventeen right-handed and four left-handed), with ages ranging between 21 and 60 years, were recruited. All participants underwent both 10 and 15 min of rs-fMRI scans. The present study evaluated the default mode network (DMN) areas for both scan durations. The areas involved were the posterior cingulate cortex (PCC), medial prefrontal cortex (mPFC), left inferior parietal cortex (LIPC), and right inferior parietal cortex (RIPC). Fifteen causal models were constructed and inverted using spectral dynamic causal modelling (spDCM). The models were compared using Bayesian Model Selection (BMS) for group studies. Result: The BMS results indicated that the fully connected model was the winning model among 15 competing models for both 10 and 15 min scan durations. However, there was no significant difference in effective connectivity among the regions of interest between the 10 and 15 min scans. Conclusion: Scan duration in the range of 10 to 15 min is sufficient to evaluate the effective connectivity within the DMN region. In frail subjects, a shorter scan duration is more favourable.

Drug addiction remains one of the most complex social problems worldwide that has yet to be resolved. In Malaysia, abuse of various types of drugs has been reported which warrants the government to take immediate strategies in managing drug addicts. Despite implementing various strategies to treat drug addiction, statistics show the number of relapses continues to skyrocket over the years. This calls for urgent attention to improve the effectiveness of substance abuse treatment services in Malaysia. Moreover, emerging evidence shows a change in trend in the type of drug being abused. This factor could potentially contribute to the ineffectiveness of the strategies employed in the treatment of substance abuse. Therefore, this review provides an overview of the major types of drugs commonly abused in Malaysia. Additionally, in an effort to search for ways to improve the effectiveness of substance abuse treatment services, we identified the public institutions responsible for managing drug addicts in Malaysia and discussed the therapeutic programs offered at the institutions. Review findings support the need for future research on the effectiveness of these therapeutic programs and recommend the implementation of evidence-based programs to improve the effectiveness of substance abuse treatments in Malaysia.

The recent novel coronavirus disease 2019 (COVID-19) outbreak has led health care providers to shift rapidly from on-site consultation towards teleconsultation. However, knowledge about patient satisfaction with teleconsultation, particularly for mental health care, is limited and demands further investigation. This study aimed to evaluate patient satisfaction with teleconsultation in mental health care during the COVID-19 pandemic. The study also aimed to identify the leading contributing factors to patient satisfaction with teleconsultation. A convenience sampling method was employed. An online survey was conducted between June 8 and August 3, 2020. A 14-item questionnaire was used to assess the patient's level of satisfaction in four domains of satisfaction. A total of 106 questionnaires were received. Respondents reported a high level of satisfaction with teleconsultation. The convenience of not having to travel to the health center for consultation was the leading contributing factor to patient satisfaction with teleconsultation. However, patients reported that they were least satisfied with teleconsultation because they could not express their feelings deeply to the provider. The current study provides preliminary evidence that teleconsultation may be a satisfactory mode of communication during the COVID-19 pandemic for mental health care in Malaysia. Most importantly, consultation in mental health care should carry on to be performed remotely to prevent the spread of infectious disease. Future research is warranted to provide a better understanding of other factors contributing to patient satisfaction with teleconsultation and ways to improve them.

Drug craving is a major crisis experienced by active or former drug abusers. The experience is characterised by an intense desire to abuse drugs for self-pleasure and satisfaction. This desire appears to be the main culprit behind the skyrocketing relapse rate. Neuroimaging has identified neural substrates associated with drug cravings. Here, we provide a mini-review of functional magnetic resonance imaging (fMRI) studies that have examined the brain regions associated with the common types of drug abuse — heroin, methamphetamine, and cocaine. Most studies use visual cues (that is drug-related images) to elicit brain responses in reward-related pathways. Studies have also focused on comparing brain activities between active drug abusers, drug-abstinent individuals, and healthy controls. Current evidence suggests that the dorsolateral prefrontal cortex (DLPFC) is associated with heroin craving, whereas the ventral striatum and medial prefrontal cortex (mPFC) underpin methamphetamine craving. Meanwhile, the hypothalamus is responsible for cocaine cravings. Compared to active drug abusers, drug-abstinent individuals demonstrated fewer brain activations when viewing drug-related images. The relationship between brain response and drug cravings is discussed in terms of brain functions and drug types. The findings offer valuable insights into the potential role of these brain areas in drug cravings and have important implications for drug addiction treatments.