Automated 6-minute walk test distance measurement and walk characterisation using a novel infrared sensor-based technique

It is common to use motorised and non-motorised treadmills in settings with space constraints for a 6-minute walk test (6MWT). This test used manual methods which are susceptible to errors. It is believed that automated techniques could eliminate the shortcomings, but this approach was not proposed by any studies. This study presented and analysed the validity of a newly-developed automated infrared-based treadmill walking monitoring system (iTMS), which as specifically designed to measure the distance and characteristics for the walk performance of a non-motorised treadmill 6MWT (nMT6MWT). This study selected 20 subjects for: The validity testing of the iTMS walked distance at five different speeds dictated by metronome beats for 2-minute and at a self-paced speed with intermittent rests for 6-minute, and the characterisation of 6-minute walk performance for distance, speed, acceleration, walking segments, and resting events. The iTMS measured distances were consistently accurate for the varying speeds during the 2-minute walk session. For the 6-minute walk en bloc and its three segments, the difference in distance (Δd) between iTMS (diTMS) and camera recording method (dCRM) showed positive biases with small LOA95% in Bland-Altman plot. The iTMS has an accurate distance measurement with ± 0.20% error of dCRM for en bloc 6-minute walk can characterise the resting events of 0.5 s and more. The iTMS is considered a viable automated method for monitoring distance and characterising nMT6MWT. It also showed the potential in addressing technical errors which may be inherent in manual 6MWT data collection methods

EEG Feature Extraction with Fast Fourier Transform for Investigating different Brain regions in Cognitive and Reasoning Activity

In this study, cortical brain activity during a pattern matching task (PMT) was measured by employing electroencephalography (EEG). The EEG data were recorded from 128 scalp locations during a pattern-matching task and in rest conditions (eyes open and eyes closed). Spectral Analysis of EEG frequency bands reflected a significant (p&lt;0.025) difference between baseline and PMT task. The EEG activity in slow waves (delta: 0.5 to 3 Hz and theta: 4 to 7 Hz) was high during PMT in frontal regions, while EEG activity in fast waves (Beta: 14 to 20 Hz and Gamma: 21 to 30 Hz) was reduced in parietal and occipital regions as compared to the frontal region. The changes in EEG medium waves (alpha: 8 to 13 Hz) was high in frontal, central, and temporal regions, while depressed in parietal, parieto-occipital and occipital regions. The results show high cortical activations in different brain regions during solving pattern-matching task as compared to baseline resting conditions. The study has implications for thinking and decision-making situation, such as object recognition, visual comparison, and consumer choice.</p

Workplace Mental State Monitoring during VR-Based Training for Offshore Environment

Adults are constantly exposed to stressful conditions at their workplace, and this can lead to decreased job performance followed by detrimental clinical health problems. Advancement of sensor technologies has allowed the electroencephalography (EEG) devices to be portable and used in real-time to monitor mental health. However, real-time monitoring is not often practical in workplace environments with complex operations such as kindergarten, firefighting and offshore facilities. Integrating the EEG with virtual reality (VR) that emulates workplace conditions can be a tool to assess and monitor mental health of adults within their working environment. This paper evaluates the mental states induced when performing a stressful task in a VR-based offshore environment. The theta, alpha and beta frequency bands are analysed to assess changes in mental states due to physical discomfort, stress and concentration. During the VR trials, mental states of discomfort and disorientation are observed with the drop of theta activity, whilst the stress induced from the conditional tasks is reflected in the changes of low-alpha and high-beta activities. The deflection of frontal alpha asymmetry from negative to positive direction reflects the learning effects from emotion-focus to problem-solving strategies adopted to accomplish the VR task. This study highlights the need for an integrated VR-EEG system in workplace settings as a tool to monitor and assess mental health of working adults

Development of Enhanced Stimulus Content to Improve the Treatment Efficacy of EEG–Based Frontal Alpha Asymmetry Neurofeedback for Stress Mitigation

The neurofeedback stimulus content has direct implications for the efficacy of the psychophysiological applications for neurofeedback modality. In particular, enhancements of neurofeedback stimulus content can facilitate improvements in the efficacy of neurofeedback applications in clinical practice. To further elaborate on this aspect, this study introduced systematic enhancements in neurofeedback stimulus content by developing enhanced neurofeedback stimulus content for stress mitigation. The enhancements included the automatic selection of colour of neurofeedback stimulus content environment and instruction messages, as well as, the adaptive selection of threshold of quantitative electroencephalogram (QEEG) features, such as frontal alpha power and frontal alpha asymmetry. The enhancements were based on the outcomes from previous research on the selection of neurofeedback stimulus content for stress mitigation. The improvement in the efficacy of neurofeedback stimulus content was measured statistically by comparing the QEEG and topographic maps. In this study, electroencephalogram data from 20 participants were acquired during multiple sessions of neurofeedback. Analysis of variance and a post hoc test were used to verify the improvement on the efficacy of the neurofeedback application for stress mitigation after the enhancements of the neurofeedback stimulus content; a t-test was used to verify the statistical significance of the stress mitigation by the neurofeedback. The results indicate that the enhancement of the developed neurofeedback stimulus content facilitated stress mitigation during the early sessions of neurofeedback. In conclusion, the efficacy of neurofeedback can be improved using the developed stimulus content with enhancements.</p