Acute Effects of Portable Dry‐EEG Neurofeedback on Classical Chinese Learning: A Three‐Arm Repeated‐Measures Study

Mental activities can be indicated by the Cognitive workload which are useful in applications like Biomedical, Human Machine Interaction and Task analysis. The mental effort applied on the Working memory at a certain given time is commonly known as Cognitive load. The EEG Signals of Cognitive Workload can be studied and classified. The features such as Entropy, Energy, Power, etc. can be extracted from the EEG signals and processed using DWT and can be used to distinguish between load levels with high accuracy. Neurophysiology provides evidences that PFC (Pre-Frontal Cortex) is integral to the control of cognitive function. Studies have proved the attentional state, the control of eye, as well as a variety of high-level behavioral functions, such as working memory, response strategies, and rule learning have a correlation with the patterns of neuronal activity in sub- regions of Pre-Frontal Cortex. So, we can emphasize that the problem- solving activities, calculations are the major tasks of frontal lobe since it does have relation with the working memory and attention but due to several mental distractions and lack of attention, it is not possible to be able to perform with complete attention. The performance lack because of mental distractions and attention could be improved with meditation. The ability to solve the problems increases because of attention. So, we can compare the EEG signals before and after meditation while solving the problems and show that the cognitive workload gets reduced after meditation with the help of extracted features. Keywords: cognitive workload, EEG signal, PFC, DWT, Entropy. Cite this Article Mohammadi B. Quazi, Ifrah Khanam, Anees F. Quazi. Analysis of impact of Meditation on Cognitive Workload using EEG Signals. Current Trends in Signal Processing . 2020; 10(1): 29–39p.

Mastication leads to an immediate enhancement in cognitive functions, including inhibitory control. Furthermore, the hardness of the food increases sympathetic nerve activity during and immediately after mastication. Hence, the cognitive function could be enhanced by increased sympathetic nerve activity. The present study aimed to investigate the effects of food hardness on cognitive inhibitory control function in humans. The participants were 23 healthy adults (19-22 years old). Experiments were conducted with two types of gummies (soft and hard). The participants ingested 13 g of gummies and performed a stop-signal task to measure cognitive inhibitory control function after they rested for 5 min. The reaction time for the stop-signal task after gummy consumption was significantly shorter in the hard gummy condition compared to the soft gummy condition (p < .05). Furthermore, the accuracy rate of the responses was also significantly higher in the hard gummy condition compared to the soft gummy condition (p < .05). The results of the present study suggest that food hardness enhances cognitive inhibitory control function in humans.

In coal mining environments, underground transport vehicles are essential for transportation operations, yet high accident rates persist due to environmental and human factors. This study investigated the effects of auditory, tactile, and combined auditory-tactile warnings on driver driving and cognitive performance in a simulated underground transport vehicle cabin. 24 participants (12 novice, 12 experienced) completed baseline driving, stimulus-response tasks and interference tasks while their driving behaviour, physiological indicators and subjective evaluations were recorded. Results showed that tactile and combined warnings improved response performance over auditory warnings, with combined warnings enhancing attentional focus and reducing reaction times, particularly for novice drivers. Tactile and combined warnings also demonstrated superior resistance to distraction. For experienced drivers, tactile alerts most effectively reduced cognitive load under high demand. These findings highlight the potential of tactile and combined warnings to improve operational safety and reduce accident risks in underground coal mine transport operations.

Transcranial alternating current stimulation (tACS) in the theta frequency range has been shown to enhance working memory (WM) performance. However, no studies have directly compared the effects of theta tACS between cognitively healthy elderly (HE) subjects and subjects with non-amnestic mild cognitive impairment (MCI). Our proof-of-concept study investigated the effects of monofocal (frontal) and bifocal (frontoparietal) theta tACS on WM in two cognitive loads in HE subjects and in subjects with MCI. In this sham-controlled, single-blinded, repeated-measures study with counterbalanced stimulation order across subjects (n = 55), theta tACS (4.51Hz, 1.5mA, 20min) was applied either over the frontal site alone or simultaneously over frontal and parietal sites. WM 2-back and 3-back tasks were performed during and after each stimulation session. In the HE group, both frontal and frontoparietal stimulations improved performance, albeit with load-dependent differences. Frontal stimulation was particularly effective in the higher cognitive load, enhancing accuracy (β = -3.87; p = .033) and reaction times (β = - .042; p = .002) in the 3-back task. Frontoparietal stimulation improved accuracy (β = -3.74; p = .027) but not reaction time (p > .22) in the 2-back task in the HE group. Frontoparietal stimulation enhanced accuracy in the 3-back task across all participants (β = 1.91; p = .043). In the MCI group, frontal stimulation led to faster reaction times in the 3-back task, although the effects were not robust. Lastly, a marginally significant improvement in reaction times was observed in a letter 2-back transfer task following frontal stimulation (β = - .034; p < .092) across all participants. Our findings indicate that theta tACS over the frontal and frontoparietal areas elicits benefits in WM performance, driven mainly by enhancements in HE subjects. The effects of stimulation varied with cognitive load and montage, suggesting that optimal stimulation parameters may differ depending on task demands. The non-amnestic MCI group did not exhibit greater improvements despite their lower baseline performance, possibly due to higher variability in pathology and compensation. Multiple sessions or alternative stimulation parameters may be needed to achieve robust effects in subjects with MCI. The study was retrospectively registered on ClinicalTrials.gov (NCT06563453).

BackgroundThe process of aging often accompanies a decline in cognitive function, postural control, and gait stability, consequently increasing the susceptibility to falls among older individuals. In response to these challenges, motor-cognitive training has emerged as a potential intervention to mitigate age-related declines.ObjectiveThis study aims to assess the acute effects of two distinct motor-cognitive training modalities, treadmill dual-task training (TMDT) and interactive motor-cognitive training (IMCT), on cognitive function, postural control, walking ability, and dual-task performance in the elderly population.MethodIn this randomized crossover study, 35 healthy elderly individuals (aged 60–75) participated in three acute training sessions involving TMDT, IMCT, and a control reading condition. Assessments of executive function, postural control, gait performance, and cognitive accuracy were conducted both before and after each session.ResultsBoth TMDT and IMCT improved executive functions. Notably, IMCT resulted in a significant enhancement in correct response rates and a reduction in reaction times in the Stroop task (p < 0.05) compared to TMDT and the control condition. IMCT also led to an increase in dual-task gait speed (p < 0.001) and showed a trend towards improved cognitive accuracy (p = 0.07). Conversely, TMDT increased postural sway with eyes open (p = 0.013), indicating a potential detriment to postural control.ConclusionThe findings suggest that IMCT holds greater immediate efficacy in enhancing cognitive function and gait stability among older adults compared to TMDT, with a lesser adverse impact on postural control. This underscores the potential of IMCT as a preferred approach for mitigating fall risk and enhancing both cognitive and physical functions in the elderly population.

BACKGROUND:It seems qualitative measurements of subjective reactions are not appropriate indicators to assess the effect of noise on cognitive performance.AIM:In this study, quantitative and combined indicators were applied to study the effect of noise on cognitive performance.MATERIAL AND METHODS:A total of 54 young subjects were included in this experimental study. The participants’ mental workload and attention were evaluated under different levels of noise exposure including, background noise, 75, 85 and 95 dBA noise levels. The study subject’s EEG signals were recorded for 10 minutes while they were performing the IVA test. The EEG signals were used to estimate the relative power of their brain frequency bands.RESULTS:Results revealed that mental workload and visual/auditory attention is significantly reduced when the participants are exposed to noise at 95 dBA level (P < 0.05). Results also showed that with the rise in noise levels, the relative power of the Alpha band increases while the relative power of the Beta band decreases as compared to background noise. The most prominent change in the relative power of the Alpha and Beta bands occurs in the occipital and frontal regions of the brain respectively.CONCLUSION:The application of new indicators, including brain signal analysis and power spectral density analysis, is strongly recommended in the assessment of cognitive performance during noise exposure. Further studies are suggested regarding the effects of other psychoacoustic parameters such as tonality, noise pitch (treble or bass) at extended exposure levels.

Cognitive workload refers to the mental effort required to perform a task and plays a vital role in cognitive functioning and daily decision-making. The precise estimation of cognitive workload can increase efficiency and decrease mental errors. EEG signals are non-invasive and trustworthy, containing useful information about mental and cognitive tasks, and are very effective in measuring cognitive workload. This study aims to classify various cognitive workload levels using EEG signals, primarily by channel selection based on the Pearson Correlation Coefficient, to reduce computational complexity and facilitate real-time applications. As time-frequency decomposition techniques can provide simultaneous time and frequency information for more accurate analysis, three techniques were adopted: Maximal Overlap Discrete Wavelet Transform (MODWT), Empirical Mode Decomposition (EMD), and a hybrid approach combining both. After decomposition, ten statistical features were extracted, and the Improved Distance Evaluation technique was employed to select the most critical features. Classification was performed on these features using three classifiers: Support Vector Machine (SVM), K-Nearest Neighbors, and Decision Tree. The findings revealed the important role of frontal EEG channels in assessing cognitive workload. Additionally, the combined use of MODWT and EMD with the SVM classifier yielded the best classification accuracy for both binary and three-class classification scenarios. The results indicate that the optimal choice of channels, combined with time-frequency decomposition methods, can significantly enhance classification accuracy while reducing system complexity in estimating cognitive workload.

It seems qualitative measurements of subjective reactions are not appropriate indicators to assess the effect of noise on cognitive performance. In this study, quantitative and combined indicators were applied to study the effect of noise on cognitive performance. A total of 54 young subjects were included in this experimental study. The participants’ mental workload and attention were evaluated under different levels of noise exposure including, background noise, 75, 85 and 95 dBA noise levels. The study subject’s EEG signals were recorded for 10 minutes while they were performing the IVA test. The EEG signals were used to estimate the relative power of their brain frequency bands.Results revealed that mental workload and visual/auditory attention is significantly reduced when the participants are exposed to noise at 95 dBA level (P &lt; 0.05). Results also showed that with the rise in noise levels, the relative power of the Alpha band increases while the relative power of the Beta band decreases as compared to background noise. The most prominent change in the relative power of the Alpha and Beta bands occurs in the occipital and frontal regions of the brain respectively.The application of new indicators, including brain signal analysis and power spectral density analysis, is strongly recommended in the assessment of cognitive performance during noise exposure. Further studies are suggested regarding the effects of other psychoacoustic parameters such as tonality, noise pitch (treble or bass) at extended exposure levels.

Age-related decline in cognitive control and general slowing are prominent phenomena in aging research. These declines in cognitive functions have been shown to also involve age-related decline in brain structure. However, most evidence in support of these associations is based on cross-sectional data. Therefore, the aim of this study is to contrast cross-sectional and longitudinal analyses to re-examine if the relationship between age-related brain structure and cognitive function are similar between the two approaches. One hundred and two participants completed two sessions with an average interval of 2 years. All participants were assessed by questionnaires, a series of cognitive tasks, and they all underwent neuroimaging acquisition. The main results of this study show that the majority of the conclusions regarding age effect in cognitive control function and processing speed in the literature can be replicated based on the cross-sectional data. Conversely, when we followed up individuals over an average interval of 2 years, then we found much fewer significant relationships between age-related change in gray matter structure of the cognitive control network and age-related change in cognitive control function. Furthermore, there was no “initial age” effect in the relationships between age-related changes in brain structure and cognitive function. This finding suggests that the “aging” relationship between brain structure and cognitive function over a short period of time are independent of “initial age” difference at time point 1. The result of this study warrants the importance of longitudinal research for aging studies to elucidate actual aging processes on cognitive control function.

Multifaceted stress factors related to infantry combat vehicle (ICV) operation may be considered as major a source of cognitive workload, which may significantly impact the performance of infantry soldiers. The available literature on the effect of ICV’s operational environment on soldier’s cognitive workload is scanty or mostly unreported. The present study was designed to observe the effect of ICV operation on the i) cognitive workload ii) cognitive performance and iii) to study the association between cognitive workload and performance. Thirty soldiers [mean(SD)- age: 31.86(2.9) years, weight: 74.40(7.7) kg, and height: 171.33(3.42) cm] volunteered for this study. Their heart rate (HR), heart rate variability (HRV) and respiratory frequency (RF) were recorded at three time points 00th-05th, 25th-30th and 55th-60th minute during the ICV operation. ‘A’ letter cancellation task (ALCT) was conducted to assess cognitive performance, before and after ICV operation. The internal temperature and relative humidity (RH) of ICV were assessed at same three time-points. Repeated measure ANOVA and Wilcoxon signed ranks test were conducted to observe significant changes in HR, HRV, RF, and cognitive performance. Association between HRV and ALCT was assessed using Pearson’s bivariate correlation. Changes were considered significant when p-value was ≤ 0.05. Significant increase in the HR and RF were observed along with significant decrease in both time and frequency domain of HRV after ICV operation. Similarly, ALCT showed a significant increase in the total and net score, and an increased error score in post-ICV operation. A strong positive correlation was observed between the ICV operation run-trial time and the increasing compartmental temperature (r=0.99) and RH (r=0.89). HRV components showed a negative correlation with ALCT measures. One hour of ICV operation resulted in increased cognitive workload and a significant decrease in the cognitive task performance. Internal temperature and RH of ICV are potential physical stress factors affecting the soldier’s workload and performance.

Cognitive control of action is associated with conscious effort and is hypothesized to be reflected by increased frontal theta activity. However, the functional role of these increases in theta power, and how they contribute to cognitive control remains unknown. We conducted an MEG study to test the hypothesis that frontal theta oscillations interact with sensorimotor signals in order to produce controlled behaviour, and that the strength of these interactions will vary with the amount of control required. We measured neuromagnetic activity in 16 healthy adults performing a response inhibition (Go/Switch) task, known from previous work to modulate cognitive control requirements using hidden patterns of Go and Switch cues. Learning was confirmed by reduced reaction times (RT) to patterned compared to random Switch cues. Concurrent measures of pupil diameter revealed changes in subjective cognitive effort with stimulus probability, even in the absence of measurable behavioural differences, revealing instances of covert variations in cognitive effort. Significant theta oscillations were found in five frontal brain regions, with theta power in the right middle frontal and right premotor cortices parametrically increasing with cognitive effort. Similar increases in oscillatory power were also observed in motor cortical gamma, suggesting an interaction. Right middle frontal and right precentral theta activity predicted changes in pupil diameter across all experimental conditions, demonstrating a close relationship between frontal theta increases and cognitive control. Although no theta-gamma cross-frequency coupling was found, long-range theta phase coherence among the five significant sources between bilateral middle frontal, right inferior frontal, and bilateral premotor areas was found, thus providing a mechanism for the relay of cognitive control from frontal to motor areas via theta signaling. Furthermore, this provides the first evidence for the sensitivity of frontal theta oscillations to implicit motor learning and its effects on cognitive load. More generally these results present a possible a mechanism for this frontal theta network to coordinate response preparation, inhibition and execution.

Cognitive control of action is associated with conscious effort and is hypothesised to be reflected by increased frontal theta activity. However, the functional role of these increases in theta power, and how they contribute to cognitive control remains unknown. We conducted an MEG study to test the hypothesis that frontal theta oscillations interact with sensorimotor signals in order to produce controlled behaviour, and that the strength of these interactions will vary with the amount of control required. We measured neuromagnetic activity in 16 healthy adults performing a response inhibition (Go/Switch) task, known from previous work to modulate cognitive control requirements using hidden patterns of Go and Switch cues. Learning was confirmed by reduced reaction times (RT) to patterned compared to random Switch cues. Concurrent measures of pupil diameter revealed changes in subjective cognitive effort with stimulus probability, even in the absence of measurable behavioural differences, revealing instances of covert variations in cognitive effort. Significant theta oscillations were found in five frontal brain regions, with theta power in the right middle frontal and right premotor cortices parametrically increasing with cognitive effort. Similar increases in oscillatory power were also observed in motor cortical gamma, suggesting an interaction. Right middle frontal and right precentral theta activity predicted changes in pupil diameter across all experimental conditions, demonstrating a close relationship between frontal theta increases and cognitive control. Although no theta-gamma cross-frequency coupling was found, long-range theta phase coherence among the five significant sources between bilateral middle frontal, right inferior frontal, and bilateral premotor areas was found, thus providing a mechanism for the relay of cognitive control between frontal and motor areas via theta signalling. Furthermore, this provides the first evidence for the sensitivity of frontal theta oscillations to implicit motor learning and its effects on cognitive load. More generally these results present a possible a mechanism for this frontal theta network to coordinate response preparation, inhibition and execution.

P1‐167: Neural basis for cognitive control enhancement in elderly people

Event Abstract Back to Event The influence of cognitive load on visual perceptual processing Ping Liu1*, Luca Cocchi2, Jason Forte1, David K. Sewell1 and Olivia Carter1 1 The University of Melbourne, School of Psychological Science, Australia 2 University of Queensland, Queensland Brain Institute, Australia Contrary to the majority of dual-task studies, recent studies show that when observers were holding information in working memory, performance on an unrelated visual perceptual task (e.g., grouping-by-proximity) was improved (increased accuracy & reduced reaction time)(Cocchi et al., 2011). These results suggest cognitive control mechanisms supporting working memory may facilitate concurrent but independent visual perceptual processing. To further explore the nature of perceptual facilitation as a function of cognitive load, two studies were run exploring whether cognitive load could influence sensitivity to low-contrast stimuli or modulate surround suppression mechanisms in low-level visual processing. A contrast detection task was employed in the first study, where participants were asked to judge the orientation (horizontal vs. vertical) of a small Gabor of various contrasts presented at one of the four corners of an imaginary square. A visual motion discrimination task eliciting surround-suppression was used in the second study, where participants were asked to judge the motion direction (left vs. right) of a large high-contrast drifting Gabor of various exposure durations presented at fovea. In both studies, the perceptual tasks were conducted during a concurrent no-, low- and high-working memory load task. Preliminary results of the first experiment showed no difference in the contrast thresholds for the detection task across conditions, suggesting that cognitive load does not enhance low-level visual perceptual processing. With data analysis for the second study ongoing, a reduction or increase in exposure thresholds for the motion task under working memory loads would suggest cognitive load either reduces or increases visual surround-suppression respectively. References Cocchi, L., Toepel, U., De Lucia, M., Martuzzi, R., Wood, S. J., Carter, O., and Murray, M. (2011). Working memory load improves early stages of independent visual processing. Neuropsychologia 49, 92-102. Keywords: dual-task performance, cognitive control, top-down modulation, working memory, Visual Perception Conference: ACNS-2012 Australasian Cognitive Neuroscience Conference, Brisbane, Australia, 29 Nov - 2 Dec, 2012. Presentation Type: Poster Presentation Topic: Sensation and Perception Citation: Liu P, Cocchi L, Forte J, Sewell DK and Carter O (2012). The influence of cognitive load on visual perceptual processing. Conference Abstract: ACNS-2012 Australasian Cognitive Neuroscience Conference. doi: 10.3389/conf.fnhum.2012.208.00079 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 25 Oct 2012; Published Online: 07 Nov 2012. * Correspondence: Miss. Ping Liu, The University of Melbourne, School of Psychological Science, Melbourne, Australia, virliu@unimelb.edu.au Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Ping Liu Luca Cocchi Jason Forte David K Sewell Olivia Carter Google Ping Liu Luca Cocchi Jason Forte David K Sewell Olivia Carter Google Scholar Ping Liu Luca Cocchi Jason Forte David K Sewell Olivia Carter PubMed Ping Liu Luca Cocchi Jason Forte David K Sewell Olivia Carter Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

The relationship between cognitive and affective control and symptoms of depression and anxiety across the lifespan: A 3-wave longitudinal study