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The handheld diagnosis and analysis are highly dependent on the physiological data in the clinical sector. Detection of the defect in the neuronal-assisted activity raises the challenge to the prevailing treatment that benefits from machine learning approaches. The congregated EEG data is then utilized in design of learning applications to develop a model that classifies intricate EEG patterns into active and inactive segments. During arithmetic problem-solving EEG signal acquired from frontal lobe contributes for intelligence detection. The low intricate statistical parameters help in understanding the objective. The mean of the segmented samples and standard deviation are the features extracted for model building. The feature selection is handled using correlation and Fisher score between {Fp1 and F8} and priority ranking of the regions with enhanced activity are selected for the classifier models to the training net. The R-studio platform is used to classify the data based on active and inactive liability. The radial basis function kernel for support vector machine (SVM) is deployed to substantiate the proposed methodology. The vulnerable regions F1 and F8 for arithmetic activity can be visualized from the correlation fit performed between regions. Using SVM classifier sensitivity of 92.5% is obtained for the selected features. A wide range of clinical problems can be diagnosed using this model and used for brain-computer interface. [ABSTRACT FROM AUTHOR]

The article discusses the diffusion of Hindu-Arabic numerals in late medieval Europe and challenges the common belief that their slow adoption was due to religious oppression or public fear. The author argues that resistance to change, the merits of Roman numerals, and varying levels of education were more significant factors in the slow transition. The spread of Hindu-Arabic numerals was limited to the wealthy and educated classes, and it wasn't until the introduction of the printing press that they became more widely accepted. The article concludes that the slow adoption was not due to oppressive religious systems but rather practical considerations and societal inequalities. [Extracted from the article]

Background: The Beck Depression Inventory-II (BDI-II) is a widely used patient-reported outcome (PRO) tool designed to screen for depressive symptoms and assess their severity. In recent years, with advancements in digital technology, the BDI-II has been adapted for use as an electronic PRO (ePRO) tool. However, to the best of our knowledge, the reliability of the smartphone version of the BDI-II has not been thoroughly investigated. This study aimed to assess the equivalence of the traditional paper and smartphone versions of the BDI-II. Methods: This study employed a randomized crossover design with adults (n = 100) from the Gunma Prefecture, Japan. Participants completed both the paper and smartphone versions of the BDI-II at 1-week intervals. The equivalence between the two versions was evaluated using the intraclass correlation coefficient (ICCagreement). Additionally, Cronbach's alpha and McDonald's omega were calculated for both versions. Results: The mean age of the participants was 19.78 years (SD = 0.94, 10% male). The ICCagreement between the paper and smartphone versions of the BDI-II was 0.81 (95% CI 0.74–0.87). Cronbach's alpha was 0.88 (95% CI 0.84–0.91) for the paper version and 0.88 (95% CI 0.84–0.91) for the smartphone version. McDonald's omega was 0.88 (95% CI 0.81–0.95) for the paper version and 0.89 (95% CI 0.85–0.93) for the smartphone version. Conclusions: The BDI-II is suitable for use in its smartphone version, and the smartphone version of the BDI-II is a valuable addition to the mental healthcare professional's toolkit. [ABSTRACT FROM AUTHOR]

Cognitive load stimulates neural activity, essential for understanding the brain's response to stress-inducing stimuli or mental strain. This study examines the feasibility of evaluating cognitive load by extracting, selection, and classifying features from electroencephalogram (EEG) signals. We employed robust local mean decomposition (R-LMD) to decompose EEG data from each channel, recorded over a four-second period, into five modes. The binary arithmetic optimization (BAO) algorithm employed to reduce the feature space and extract multi-domain features from modes, thereby optimizing classification performance. Using six optimized machine learning (ML) classifiers, we conducted an exhaustive study that encompassed both lead-wise and overall feature classification. We improved our method by combining R-LMD-based multi-domain features with BAO and optimized ensemble learning (OEL) classifiers. It was 97.4% accuracy (AC) at finding cognitive load in the MAT (mental arithmetic task) dataset and 96.1% AC at finding it in the STEW (simultaneous workload) dataset. In the same vein, this work introduces lead-wise cognitive load detection, which offers both temporal and spatial information regarding brain activity during cognitive tasks. We analyzed the 19 and 14 leads for the MAT and STEW, respectively. The F3 lead was notably noteworthy in its ability to analyze a variety of cognitive tasks, obtaining the maximum classification AC of 94.5% and 94%, respectively. Our approach (R-LMD+BAO+OEL) outperformed existing state-of-the-art techniques in cognitive load detection. [ABSTRACT FROM AUTHOR]

Objective: The literature on clinical psychophysiology highlights the possibility of using Heart Rate Variability (HRV) as an index of psychophysical balance and resilience to stress. This study investigates the differences in stress reactivity and subsequent recovery between a group of migraineurs and healthy controls. Methods: Socio-demographic (i.e., sex, age, profession, marital status, and level of education) and psychophysiological (HR and HRV) measures of a group of thirty subjects with migraine (26 migraineurs without aura (86.7%), 2 migraineurs with aura (6.7%), and 2 migraineurs with and without aura (6.7%)) and from thirty healthy control subjects were collected. In particular, HRV was analyzed through frequency-domain parameters, including Low-Frequency (LF; 0.04–0.15 Hz) and High-Frequency (HF; 0.15–0.4 Hz) bands as well as LF/HF ratio during a Psychophysiological Stress Profile (PSP) structured in seven phases: (1) Baseline, (2) Objective stressor 1 (Stroop Test), (3) Rest 1, (4) Objective stressor 2 (Mental Arithmetic Task), (5) Rest 2, (6) Subjective stressor (recount a significant life event), and (7) Rest 3. The LF, HF, and LF/HF ratio values were transformed into a logarithmic scale (i.e., log-LF, log-HF, and log LF/HF ratio). Additionally, LF and HF were converted into normalized units (0-100) (i.e., LF% and HF%) which, in turn, were used to obtain reactivity and recovery to stress through delta values (Δ) calculation. Results: Subjects with migraine reported greater ΔLF% levels of reactivity and recovery to subjective stressor, demonstrating a prevalence of sympathetic activity while recounting a personal life event. At the same time, a lowering of the same values was found in the subjects of the group control. Discussion: Our results underline the importance of conducting a psychophysiological assessment in patients with headaches because reduced stress management skills could influence the clinical manifestations of the disease, considering stress as one of the most common triggers for migraine patients. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Kirsehir Education Faculty is the property of Journal of Kirsehir Education Faculty and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article discusses the increasing trend of families seeking one-on-one tutoring for their children, particularly in affluent areas like Brentwood, Tennessee. The rise in private tutoring centers has been significant, with many students also turning to digital tutoring platforms. Research indicates that tutoring can help students catch up on missed learning and improve academic outcomes, especially in foundational skills like math and reading. The use of technology has made tutoring more accessible and affordable, with some experts suggesting that tutoring may be filling gaps in traditional education systems. [Extracted from the article]

Muscle sympathetic nerve activity (MSNA) responsiveness to mental stress is highly variable between individuals. Although stress perception has been posited as a contributor to the MSNA variability during mental stress, prior studies have been inconclusive. Furthermore, the importance of stress appraisal and coping on MSNA reactivity to mental stress has not been investigated. We hypothesize that appraisal of mental stress as a threat (i.e., perceived demands of stress exceed coping resources) versus a challenge (i.e., perceived coping resources sufficient for demands of stress) would be associated with greater MSNA reactivity. Twenty healthy adults (11 males, 9 females, 21 ± 3 yr, 23 ± 3 kg/m2) participated. Beat-by-beat blood pressure (finger plethysmography), heart rate (electrocardiography), and MSNA (microneurography) were recorded during a 10-min quiet rest followed by the Trier Social Stress Test (TSST). After each phase of the TSST (i.e., speech prep, speech, and mental arithmetic), participants reported threat versus challenge appraisal. Endorsement of a threat appraisal was positively associated with changes in MSNA burst frequency (r = 0.548, P = 0.018), burst incidence (r = 0.599, P = 0.009), and total MSNA (r = 0.697, P = 0.037) during the speech stress period. Moreover, increases in threat appraisal across tasks was associated with elevated MSNA burst frequency (r = 0.531, P = 0.023), incidence (r = 0.512, P = 0.030), and total MSNA (r = 0.727, P = 0.027) responsiveness. These findings support an association between stress appraisal processes and postganglionic sympathetic neural reactivity to psychosocial stress and may partially explain interindividual variability in MSNA responses to mental stress. NEW & NOTEWORTHY: The present study investigated the association between stress appraisal and muscle sympathetic nerve activity (MSNA) reactivity to the Trier Social Stress Test. Appraisal of the stress task as a threat (i.e., perceived inability to cope with the demands of the task) was associated with exaggerated MSNA reactivity to mental stress in humans. Threat appraisal is associated with exaggerated sympathetic reactivity to stress, potentially underlying the commonly observed interindividual variability in MSNA responsiveness to mental stress. [ABSTRACT FROM AUTHOR]

Abstract Background Theta-gamma coupling (TGC) describes the modulation of gamma oscillations by the theta phasic activity, which is crucial for processes such as the ordering of information during working memory (WM) performance. The mental arithmetic (MA), which involves performing calculations with numbers, is a crucial tool for evaluating and understanding the sensory processing and management abilities of WM. Evaluating TGC may provide greater insight into the neural mechanisms mediating WM deficits in panic disorder (PD). Methods Medical and electroencephalography (EEG) records of psychiatric outpatient clinic between 1 March 2020 and 30 September 2023 were retrospectively reviewed. A total of 34 PD patients and 34 age- and sex-matched healthy controls (HCs) underwent EEG to assess the overall functional interaction of the brain using multi-channel EEG analysis, focusing on specific brain regions including the frontal, temporal, parietal, and occipital lobes. EEG recordings were conducted during two sessions: a 5-min eyes-closed resting-state (RS) and a subsequent 5-min eyes-closed MA. The TGC and the spectral power of the theta and gamma frequency bands, which are well known to be associated with WM, were analysed. Results Compared to those in HCs, TGC and theta power were significantly attenuated in PD patients. When analysing both HCs and PD patients together, RS TGC and relative theta power were negatively correlated with state anxiety and perceived stress scores, respectively. In contrast, TGC and relative theta power during the MA condition were positively correlated with the MA performance. Specifically, in PD patients, RS theta power across all electrodes was significantly negatively correlated with the Hamilton Anxiety Scale (HAMA) score. Linear regression analysis revealed that theta power in the T5 channel remained negatively correlated with pathological anxiety as measured by the HAMA score, even after controlling for other confounding factors. Conclusions This study highlights significant alterations in TGC and theta power in PD patients. PD patients exhibit reduced TGC and theta power compared to HCs, indicating deficits in the neural mechanisms underlying anxiety and/or WM in PD. These insights contribute to a better understanding of the neural basis of WM deficits in PD and suggest potential avenues for targeted therapeutic interventions.

Key points Chronic kidney disease (CKD) is characterized by overactivation of the sympathetic nervous system (SNS) that leads to increased risk of cardiovascular disease. This study was conducted to evaluate the effects of a Mindfulness‐Based Stress Reduction (MBSR) programme on SNS activity in CKD patients. Participants with CKD stages III–IV were randomized to the 8 week MBSR programme or Health Enhancement Program (HEP; a structurally parallel, active control group). Intraneural measures of SNS activity directed to muscle [muscle sympathetic nerve activity (MSNA)] via microneurography was recorded at rest and during stress manoeuvres (mental arithmetic, handgrip exercise and cold pressor test). Data analyses were performed based on the intent‐to‐treat principle. In total, 29 participants (64 ± 9 years; 86% males) completed the intervention with 17 in the MBSR and 12 in the HEP groups. There was a significant Group (MBSR vs. HEP) by Time (baseline vs. post‐intervention) interaction in MSNA reactivity to mental stress (P = 0.029), with a significant reduction in the mean ∆MSNA over 3 min of mental arithmetic at post‐intervention (10.3 ± 4.2–5.9 ± 5.6 bursts/min, P < 0.001; Hedges’ g = −0.858, 95% confidence interval [−1.578, −0.167]), while no change was observed within the HEP group (P = 0.818). Reduced ∆MSNA during handgrip exercise was also observed, while ∆MSNA during the cold pressor test and resting MSNA remained unchanged in both groups from baseline to post‐intervention. In this randomized controlled trial, patients with CKD had a reduction of sympathetic reactivity during mental stress and static handgrip exercise following 8 weeks of MBSR but not after HEP. Our findings demonstrate that mindfulness training is feasible and may have clinically beneficial effects on autonomic function in CKD. Question: Does the Mindfulness‐Based Stress Reduction (MBSR) programme reduce sympathetic activity in patients with chronic kidney disease (CKD)? Finding: In this randomized controlled trial including 29 patients with CKD, 8 weeks of MBSR decreased sympathetic reactivity to mental stress compared to the control Health Enhancement Program (HEP). Meaning: These finding suggest that mindfulness training may have clinically beneficial effects on autonomic function in CKD. [ABSTRACT FROM AUTHOR]

Single‐subject research can provide adequate justification when developing successful evidence‐based educational practices for children with autism spectrum disorder (ASD), which can help such students thrive academically. This research investigates whether point‐of‐view video modelling effectively improved the word problem‐solving addition performances of primary‐school‐aged students with ASD. The effectiveness of the intervention on each participant's ability to solve single‐digit addition by a single digit, effectively view the video on a tablet and generalise a learned skill was investigated by utilising a design that included several participant baselines. All participants saw an improvement in their ability to solve simple addition problems due to using point‐of‐view video modelling. Between the baseline and intervention phases, each participant's rate of digits correctly entered per minute and total number of steps completed significantly increased. A generalisation phase was performed at home. After receiving the intervention, people with ASD could independently complete word problems involving addition with a single digit. The findings suggest that this technology could practically support the education of the growing number of children and young people with ASD by mollifying the particular learning obstacles their impairment brings. [ABSTRACT FROM AUTHOR]

Background: Globus pharyngeus could be described as a benign sensation of lump or foreign object in the throat. The etiology of the globus as a solitary syndrome is still unknown, but it is proposed that stress could have an important role in symptom emergence. Aims: To evaluate the autonomic nervous regulation in patients with globus compared to healthy controls in reaction to stress. Methods: Patients included in the study were diagnosed based on ROME IV criteria for Disorders of Gut Brain Interaction. Besides globus, the patients did not suffer any other substantial medical condition. As a control group, measurement of healthy volunteers was performed. Both groups underwent the same stress protocol assessment in the same laboratory settings. The protocol consist of two types of stressors: cold pressor test and mental arithmetic test to test different types of autonomic reactivity. Results: Baroreflex sensitivity was significantly decreased in patients compared to controls in all phases of the protocol. Low-frequency band of systolic blood pressure variability was significantly increased during both stress phases in patients compared to controls. High-frequency band of heart rate variability was significantly decreased in patients compared to controls during the both of the stress phases. Conclusion: The results of this study shows discrete abnormalities in complex autonomic reflex control which are predominantly manifested in response to stressful stimuli indicating altered neurocardiac regulation as a reaction to stress associated with globus pharynegus. This fact could have an important role in the personalized management of globus patients such as biofeedback. [ABSTRACT FROM AUTHOR]

The article delves into the achievements of African American students at the Madame C. J. Walker Grade School in Joppa, Illinois, between 1919 and 1955, led by teacher Alvin H. Caldwell. Despite facing challenges like limited resources and overcrowding, students thrived academically and went on to pursue higher education and successful careers. The school's history showcases the commitment of African American communities to education and the resilience of students and educators in segregated one-room schools. Alvin Caldwell's teaching career at the Madame C. J. Walker Grade School is detailed, highlighting his dedication to preparing students for future success despite obstacles like funding shortages and discrimination. The text emphasizes the accomplishments of Caldwell's former students, who excelled academically and professionally, crediting his mentorship for their achievements. Caldwell's impact as an educator and community leader underscores the vital role of African American teachers in delivering quality education and inspiring future generations. [Extracted from the article]

Background: Theta-gamma coupling (TGC) describes the modulation of gamma oscillations by the theta phasic activity, which is crucial for processes such as the ordering of information during working memory (WM) performance. The mental arithmetic (MA), which involves performing calculations with numbers, is a crucial tool for evaluating and understanding the sensory processing and management abilities of WM. Evaluating TGC may provide greater insight into the neural mechanisms mediating WM deficits in panic disorder (PD). Methods: Medical and electroencephalography (EEG) records of psychiatric outpatient clinic between 1 March 2020 and 30 September 2023 were retrospectively reviewed. A total of 34 PD patients and 34 age- and sex-matched healthy controls (HCs) underwent EEG to assess the overall functional interaction of the brain using multi-channel EEG analysis, focusing on specific brain regions including the frontal, temporal, parietal, and occipital lobes. EEG recordings were conducted during two sessions: a 5-min eyes-closed resting-state (RS) and a subsequent 5-min eyes-closed MA. The TGC and the spectral power of the theta and gamma frequency bands, which are well known to be associated with WM, were analysed. Results: Compared to those in HCs, TGC and theta power were significantly attenuated in PD patients. When analysing both HCs and PD patients together, RS TGC and relative theta power were negatively correlated with state anxiety and perceived stress scores, respectively. In contrast, TGC and relative theta power during the MA condition were positively correlated with the MA performance. Specifically, in PD patients, RS theta power across all electrodes was significantly negatively correlated with the Hamilton Anxiety Scale (HAMA) score. Linear regression analysis revealed that theta power in the T5 channel remained negatively correlated with pathological anxiety as measured by the HAMA score, even after controlling for other confounding factors. Conclusions: This study highlights significant alterations in TGC and theta power in PD patients. PD patients exhibit reduced TGC and theta power compared to HCs, indicating deficits in the neural mechanisms underlying anxiety and/or WM in PD. These insights contribute to a better understanding of the neural basis of WM deficits in PD and suggest potential avenues for targeted therapeutic interventions. [ABSTRACT FROM AUTHOR]

Introduction: Acupuncture on the acupuncture point GV20 has been considered effective for managing psychoneurological disorders since ancient times, and GV20 is now regularly used to treat stress-related diseases (SRDs), including psychoneurological disorders. Although reports indicating that acupuncture stimulation of GV20 alone regulates cerebral blood flow (CBF) in brain regions associated with SRDs have been scattered, from the perspective of the need for earlier action, the effects on subjective stress as self-reported in the stress state of healthy individuals and CBF changes in related prefrontal cortex (PFC) subregions, which is based as underlying mechanism, remain unclear. Therefore, there is a need to explore effective methods for analyzing such effects. Methods: Multiple consecutive mental arithmetic tasks were performed to induce sufficient stress in healthy university students. Real acupuncture or sham acupuncture was performed on GV20, and subjective stress and CBF changes in PFC subregions were observed before and after acupuncture using functional near-infrared spectroscopy, which were analyzed based on the general linear model method and correlation analysis. Results: Subjective stress was suppressed and recovered significantly faster in the true acupuncture group than in the sham acupuncture group. Furthermore, significant negative correlations were found between subjective stress and CBF in several PFC subregions during and after the tasks, with more correlated regions on the left side than on the right side of the PFC. Among them, the CBF of the left ventrolateral PFC (vl-PFC) was suggested to be maintained in the true acupuncture group under repeated tasks load, which was inferred to be correlated with delayed decreases in subjective stress after acupuncture. Discussion: This pilot study showed that fNIRS is feasible for assessing delayed PFC inhibition in acute stress by acupuncture on GV20. Acupuncture treatment on GV20 resulted in early suppression of subjective stress and early recovery. The neuroscientific rationale for this finding may lie in its effect on maintaining CBF in the left vl-PFC related to delayed inhibition of subjective stress, and would make it reasonable to apply acupuncture to GV20 in healthy individuals. Larger studies are needed to corroborate these findings and obtain reliable conclusions. [ABSTRACT FROM AUTHOR]

Aim: This study aims to explore the physiological effect of forest bathing on stress management. Methods: A total of 29 volunteers participated in this pre-post design, which lacked a control group. Several physiological parameters were recorded, including heart rate (HR), heart rate variability (HRV), electrodermal activity (EDA), blood pressure (BP), immunoglobulin A (IGA), and salivary cortisol (sCort). Additionally, the Perceived Stress Scale (PSS-10) was administered before forest exposure. Measurements were taken before and after participants spent 2 days fully immersed in a forest environment. To further assess stress management, participants completed a Mental Arithmetic Task (MAT) before and after forest immersion, during which EDA, HRV, and HR were monitored using an Empatica E4 wristband. Measurements were taken at baseline, during MAT, and afterward (recovery). Results: Participants exhibited moderate perceived stress levels before forest immersion (mean PSS-10 = 21.22, SD = 3.78). Post-forest exposure, there was a significant decrease in sCort (p < 0.05) and EDA (p < 0.001), while HRV increased (p < 0.001), and diastolic blood pressure rose (p < 0.05). ANOVA results from the MAT showed a significant increase in parasympathetic activity across all conditions post-immersion (p < 0.05), except during recovery, while EDA decreased in all conditions post-forest exposure (p < 0.05). Conclusion: Shinrin-yoku significantly improved stress management at a physiological level and could be a valuable intervention for individuals experiencing stress. However, longitudinal studies with a control group are necessary to determine whether these effects are sustained over time. Nonetheless, this study highlights the potential benefits of forest immersion for stress reduction by enhancing sympathovagal balance and the adaptability of the stress response system. Created with biorender.com. [ABSTRACT FROM AUTHOR]

AbstractPurpose:Materials and methods:Results and Discussion:\nIMPLICATIONS FOR REHABILITATIONFocusing on individuals with visual impairment, this study investigated the effects of spatial learning using tactile maps on orientation accuracy by path integration in physical and mental imagery walking scenarios.Twelve blindfolded sighted people learned nonlooping routes with two corners using tactile maps composed of volumetric raised-line elements, then navigated the routes physically and mentally. At four orientation points along the route—the starting point, Corner A, Corner B, and the endpoint—participants indicated the direction of the other points by aligning a raised, tapered rectangle attached to a horizontal digital protractor.During the physical and mental walking tasks, the participants’ mean orientation error values, representing the error in angle from the correct orientation, approximated zero for all orientation directions. However, the mean absolute error, i.e. the absolute value of the orientation error, ranged from 12.5° to 32.5° across different orientation points and tasks. As the participants followed the route, the absolute error relative to the next direction of travel increased, and the absolute errors for orientation points they had passed were substantially large. These results indicate that although tactile maps do not always enable precise orientation, they provide navigators with a surveyed spatial understanding that assists orientation through path integration. Furthermore, the mean difference in orientation error between mental and walking tasks measured on the same route for all directions was not significantly different from zero. This suggests that mental imagery walking with the tactile map helps predict orientation performance by path integration in navigators without vision.Learning routes using a tactile map is a useful approach for facilitating orientation based on path integration, even though it does not completely eliminate orientation-related errors.The orientation task, which uses a tactile map to perform the mental walking task, has potential as a new evaluation method for orientation ability through path integration in people with visual impairment.Learning routes using a tactile map is a useful approach for facilitating orientation based on path integration, even though it does not completely eliminate orientation-related errors.The orientation task, which uses a tactile map to perform the mental walking task, has potential as a new evaluation method for orientation ability through path integration in people with visual impairment. [ABSTRACT FROM AUTHOR]

Complexity characterizes behaviour of all physiological systems whose components interact in multiple ways usually quantified by entropy techniques. However, complexity analysis regarding electrodermal activity (EDA)-related sympathetic cholinergic nervous system is rare. Thus, we aimed to study EDA dynamics complexity changes from aspect of various embedding dimensions (m) and timescales (t) (sample entropy (SampEn) with m ∈ <2,7>, and multiscale entropy (MSE) in t ∈ <1,20>) in association with traditionally used EDA indices (skin conductance level (SCL) and nonspecific skin conductance responses (NS.SCRs)) to mental stress (mental arithmetic test - MAT) in healthy participants at critical adolescent age. The cohort (total group) consisted of 60 adolescents (17.5 ± 0.5 yrs) divided into three groups: Group-1: early (13.1 ± 0.3 yrs), Group-2: middle (16.6 ± 0.2 yrs) and Group-3: late (22.9 ± 0.1 yrs) adolescence. SampEn (m > 2) and MSE (for all τ) were significantly higher during MAT than baseline in total group and Group-2 (p < 0.05). Index MSE for all t was significantly higher during MAT than baseline in total group, and Group-2; for t ∈ <2,13> in Group-1 (p < 0.05). Additionally, while SCL was significantly higher during MAT than baseline in all groups, NS.SCRs was lower during stress only in Group-3 (p < 0.05). In conclusion, this study revealed distinct EDA complexity characteristics in individual examined groups indicating importance of complexity evaluation in stress-related sympathetic regulatory mechanisms within individual adolescent age ranges. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Curriculum & Teaching Methodology / Maǧallaẗ al-Manāhiǧ wa-Turūq al-Tadrīs is the property of Arab Journal of Sciences & Research Publishing (AJSRP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We review the evidence for the conceptual association between arithmetic and space and quantify the effect size in meta-analyses. We focus on three effects: (a) the operational momentum effect (OME), which has been defined as participants' tendency to overestimate results of addition problems and underestimate results of subtraction problems; (b) the arithmetic cueing effect, in which arithmetic problems serve as spatial cues in target detection or temporal order judgment tasks; and (c) the associations between arithmetic and space observed with eye- and hand-tracking studies. The OME was consistently found in paradigms that provided the participants with numerical response alternatives. The OME shows a large effect size, driven by an underestimation during subtraction while addition was unbiased. In contrast, paradigms in which participants indicated their estimate by transcoding their final estimate to a spatial reference frame revealed no consistent OME. Arithmetic cueing studies show a reliable small to medium effect size, driven by a rightward bias for addition. Finally, eye- and hand-tracking studies point to replicable associations between arithmetic and eye or hand movements. To account for the complexity of the observed pattern, we introduce the Adaptive Pathways in Mental Arithmetic (APiMA) framework. The model accommodates central notions of numerical and arithmetic processing and helps identifying which pathway a given paradigm operates on. It proposes that the divergence between OME and arithmetic cueing studies comes from the predominant use of non-symbolic versus symbolic stimuli, respectively. Overall, our review and findings clearly support an association between arithmetic and spatial processing. [ABSTRACT FROM AUTHOR]

Cognitive tasks have become quite popular in recent years. Understanding this sort of neurological research, its real-world applications, and how it may be improved in future studies are crucial. For this purpose, our study compares the classification accuracies for various segment lengths and overlap ratios for EEG recordings collected from 36 healthy volunteers during mental arithmetic tasks. EEG features are extracted from brain signals using the wavelet spectrum and the sample length and the overlap ratio of the sliding Windows are used as parameters. Feature selection was conducted using Correlation-Based and ReliefF feature selections. Subsequently, for classification results, Support Vector Machine, Random Forest, C4.5 Algorithm and k-Nearest Neighbor algorithms were employed, with the outcomes supported by the F1-score and Matthew's correlation coefficient. Therefore, the reliability of the obtained results has been ensured. In the comparisons obtained, the best average results for Accuracy, F1-score, and Matthew's correlation coefficient were found to be 0.990, 0.987, and 0.975 respectively, when applying the ReliefF feature selection method with the Support Vector Machine classifier. [ABSTRACT FROM AUTHOR]

Functional near-infrared spectroscopy (fNIRS), an optical neuroimaging technique, has been widely used in the field of brain activity recognition and brain-computer interface. Existing works have proposed deep learning-based algorithms for the fNIRS classification problem. In this paper, a novel approach based on convolutional neural network and Transformer, named CT-Net, is established to guide the deep modeling for the classification of mental arithmetic (MA) tasks. We explore the effect of data representations, and design a temporal-level combination of two raw chromophore signals to improve the data utilization and enrich the feature learning of the model. We evaluate our model on two open-access datasets and achieve the classification accuracy of 98.05% and 77.61%, respectively. Moreover, we explain our model by the gradient-weighted class activation mapping, which presents a high consistent between the contributing value of features learned by the model and the mapping of brain activity in the MA task. The results suggest the feasibility and interpretability of CT-Net for decoding MA tasks. [ABSTRACT FROM AUTHOR]

Mental arithmetic makes it possible to perform arithmetic operations without the need to use notes or other external aids, such as calculators or manipulatives. The objective of the research was to design and validate a didactic strategy for the development of mental arithmetic skills of addition and subtraction in third year students of the "Luis Alfredo Noboa Icaza" Educational Unit, Guayaquil, Ecuador. The researchers developed a research process based on the conceptions of the mixed approach, through a pre-experimental design of explanatory research, with pre-test and post-test measurements in a single group. The scientific research carried out was structured in the phases of initial characterization, design of the didactic strategy and validation. The initial characterization phase revealed achievements and insufficiencies related to the establishment of relationships between the numbers to be calculated, limitations of the students' ability to use and relate numbers and operations. The didactic strategy designed is structured in the following components: general objective, didactic guidelines, preparation stage, execution stage and control and feedback stage. The evaluation by experts and the implementation of the didactic strategy made it possible to demonstrate that the result provided constitutes a valid orientation to direct the pedagogical activity of the teacher in the process of developing mental calculation skills of addition and subtraction, in such a way as to promote the automation of skills for the successful performance of mental calculation in third year students. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Special Needs Sciences is the property of Beni Suef University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Eye tracking technology is a high-potential tool for different mathematic cognition research areas. Moreover, there is a dire need for more studies that provide detailed information on the quality of registered eye data. This study aimed to illustrate the applicability of eye tracking in the examination of mathematical cognition, focusing specifically on primary school students completing a computerized mental arithmetic task. Results suggested that the eye tracking device effectively captured high-quality eye movement data when primary school children engaged in this specific task. Furthermore, significant negative correlations have been found between task performance and number of eye fixations. Finally, eye movements distinctions between “Areas of Interest” have been found, indicating different visual tracking associated with different components of arithmetic calculations. This study underscores the extensive possibilities for future research employing eye tracking devices during computerized calculation tasks as assessment tools to explore the complex visual and cognitive processes.

Biological motion perception is an essential part of the cognitive process. Stress can affect the cognitive process. The present study explored the intrinsic ERP features of the effects of acute psychological stress on biological motion perception. The results contributed scientific evidence for the adaptive behavior changes under acute stress. After a mental arithmetic task was used to induce stress, the paradigm of point-light displays was used to evaluate biological motion perception. Longer reaction time and lower accuracy were found in the inverted walking condition than in the upright walking condition, which was called the "inversion effect". The P2 peak amplitude and the LPP mean amplitude were significantly higher in the local inverted perception than in the local upright walking condition. Compared to the control condition, the stress condition induced lower RT, shorter P1 peak latency of biological motion perception, lower P2 peak amplitude and LPP mean amplitude, and higher N330 peak amplitude. There was an "inversion effect" in biological motion perception. This effect was related to the structural characteristics of biological motion perception but unrelated to the state of acute psychological stress. Acute psychological stress accelerated the reaction time and enhanced attention control of biological motion perception. Attention resources were used earlier, and less attentional investment was made in the early stage of biological motion perception processing. In the late stage, a continuous weakening of inhibition was shown in the parieto-occipital area. [ABSTRACT FROM AUTHOR]

The purpose of the current study was to investigate the contribution of different cognitive processes to specific math abilities in students with autism spectrum disorder (ASD) and typically developing (TD) students. The study involved a group of students with ASD without intellectual disabilities (n = 26) and a group with TD students (n = 52). The two groups aged from six to 20 years old and were matched for age, sex ratio and visuospatial reasoning. To assess math abilities, four math tasks were administered: arithmetic facts, mental calculation, mathematical inferences and math problem solving. Concerning cognitive processes, participants were tested on vocabulary, verbal working memory, visuospatial working memory, response inhibition and interference control. The group with ASD showed lower scores on all specific math measures than the TD group; cognitive processes differently contributed to diverse math abilities, and vocabulary and verbal working memory were stronger associated to specific math abilities in the group with ASD than in the TD group. The current results suggest that students with ASD had lower math abilities that are generalized to different math tasks. Implications for research and clinical assessment and intervention were discussed. [ABSTRACT FROM AUTHOR]

Objective: This longitudinal study aimed to quantitatively document and evaluate the implementation and outcomes of the Open Dialogue (OD) approach within Italian Mental Health Departments (MHDs), focusing on the ratings of OD-network meetings by patients and their families and assessing the clinical outcomes over a span of 12 months. Results: Over the course of the study, 58 patients participated in 517 OD-network meetings, demonstrating a high level of satisfaction with the care received, as evidenced by the Session Rating Scale (SRS) and Outcome Rating Scale (ORS). Clinically, significant improvements were observed in the Global Assessment of Functioning (GAF), Clinical Outcomes in Routine Evaluation (CORE-OM), and the Lubben Social Network Scale (LSNS), indicating enhanced psychological and social functioning. The SRS scores showed that satisfaction with the meetings increased over time, while the ORS indicated that both patients and their social networks perceived gradual improvements throughout the therapy. Conclusion: The OD approach within Italian MHDs was successfully implemented and well-received by patients and their social networks, yielding significant clinical improvements. These findings suggest the feasibility and effectiveness of integrating the OD model into the Italian public mental health system, supporting its potential for broader application in diverse healthcare settings. The study highlights the importance of continuous engagement and evaluation to maintain high standards of practice and suggests that OD can be a valuable addition to existing mental health care practices, promoting recovery through inclusive, dialogue-based interventions. [ABSTRACT FROM AUTHOR]

While individuals fail to assess their mental health subjectively in their day-to-day activities, the recent development of consumer-grade wearable devices has enormous potential to monitor daily workload objectively by acquiring physiological signals. Therefore, this work collected consumer-grade physiological signals from twenty-four participants, following a four-hour cognitive load elicitation paradigm with self-chosen tasks in uncontrolled environments and a four-hour mental workload elicitation paradigm in a controlled environment. The recorded dataset of approximately 315 hours consists of electroencephalography, acceleration, electrodermal activity, and photoplethysmogram data balanced across low and high load levels. Participants performed office-like tasks in the controlled environment (mental arithmetic, Stroop, N-Back, and Sudoku) with two defined difficulty levels and in the uncontrolled environments (mainly researching, programming, and writing emails). Each task label was provided by participants using two 5-point Likert scales of mental workload and stress and the pairwise NASA-TLX questionnaire. This data is suitable for developing real-time mental health assessment methods, conducting research on signal processing techniques for challenging environments, and developing personal cognitive load assistants. [ABSTRACT FROM AUTHOR]

The article explores the concept of "doxastic agent's awareness," which refers to an individual's awareness of their beliefs. The author argues that this awareness extends beyond intentional actions and includes beliefs as well. They propose that this awareness is grounded in our experience of performing mental actions, such as deliberating and forming beliefs. The article also discusses the significance of doxastic agent's awareness for self-knowledge and the study of agency. The author remains neutral on the preferred account of doxastic agency and provides funding information and a list of works cited. [Extracted from the article]

Previous research has shown the importance of conducting early interventions in mathematics in disadvantaged children. Solving arithmetical word problems is a field in which children particularly fail. In this study, preschoolers from disadvantaged French public schools (n = 101; Mage = 5–6) were taught strategies for using fingers to solve arithmetic word problems and compared with a control group. The intervention consisted of collective rituals based on learning finger patterns and 7 sessions spread over 4 weeks, for about 20 min, focusing on explaining how to use the fingers to solve problems. The results showed that the intervention has a significant post-test impact on the targeted transformation problem-solving skill and that children with lower performances in problem-solving at the pre-test benefited more from the intervention. The intervention also indirectly benefited the other problem-solving skills. However, there was no intervention effect on the arithmetic addition task. Our research highlights that an intervention focused on the explicit teaching of finger strategies for problem-solving can be successfully implemented into ecological learning contexts, especially in disadvantaged areas. [ABSTRACT FROM AUTHOR]

Early detection of and relevant information on children's mathematical difficulties is important to initiate targeted teaching and intervention. This study investigated the extent to which strategy use in single-digit addition provides additional predictive information about 61 grade one children's (6-year-old) mathematical achievement 3 years later that is not available from a standardised mathematics achievement test. Four predictors available in year one (arithmetic strategy use, mathematical achievement, non-verbal reasoning skills and sex) explained 54% of the variation in grade four mathematics achievement. Arithmetic strategy use was the most important single predictor of year four mathematics achievement (R2 = 30%) and explained an additional 12% variation if added to a model comprised by the three other year one predictors. This result suggests that systematically obtained measures of how young children solve single-digit arithmetic problems might provide useful information about their foundational number knowledge, which in turn may reveal how well they achieve later in school. [ABSTRACT FROM AUTHOR]

The effect of stress on risk‐taking or risk‐averse behavior in decision‐making has been inconclusive in previous research, with few studies revealing the underlying neural mechanisms. This study employed event‐related potentials technique and combined a social cold pressor assessment test with a mental arithmetic task to induce stress responses, aiming to investigate the influence of exogenous stress on the risk decision‐making process. Stress induction results indicated that, in addition to raising heart rate and blood pressure, stress responses were accompanied by enhanced negative emotions, diminished positive emotions, and alterations in neural activity. The outcomes of risk decision‐making showed that stress did not significantly affect risk preference or time of choice but did reduce the feedback‐related negativity/reward positivity, with a particularly significant effect observed for large outcomes. Stress also altered the amplitude of the P3 component, with stress decreasing the P3 value for winning outcomes relative to losing outcomes. The study suggests that understanding how stress affects risk preference should consider the emotional valence induced by stress. Contrary to the reward sensitivity hypothesis, stress weakened reward sensitivity. Stress led to changes in the allocation of cognitive resources for outcome evaluation: compared to negative outcomes, stress reduced cognitive resources for positive outcomes, which might be related to the enhanced negative emotions induced by stress. The study highlights the importance of focusing on the subjective emotional experience induced by stress in future research on stress and risk decision‐making. We find that stress with negative emotions weakens reward sensitivity, which challenges the reward sensitivity hypothesis. Stress also modifies cognitive resource allocation for outcome evaluation: compared to negative outcomes, stress reduced cognitive resources for positive outcomes. This study underscores the significance of incorporating emotional experiences induced by stress into future investigations about stress and risk decision‐making. [ABSTRACT FROM AUTHOR]

When faced with the need to transform an object, idea, or situation, people have a tendency to favor adding new components rather than removing existing ones. This is called the additive bias. Previous research, along with historical and anecdotal examples, shows that this bias may significantly reduce problem‐solving abilities and have a detrimental impact on the innovation process. In this study, our objective was to develop a novel tool, the additive bias implicit association test (ad‐IAT), to investigate the reasons underlying people's preference for additive actions. By using this tool, we empirically demonstrated that people displayed an inherent tendency to assign a positive valence to additive concepts and to perceive additive actions as safer and more functional than subtractive concepts. Importantly, we also found that implicit preference for addition resulted in participants favoring additive actions while neglecting subtractive alternatives when engaged in a problem‐solving task. Collectively, our series of experiments substantiated the effectiveness of our ad‐IAT in uncovering and quantifying the additive bias. This, in turn, provided a deeper comprehension of the underlying factors contributing to the bias and its impact on people's behavior. [ABSTRACT FROM AUTHOR]

Performing dual-task (DT) activities is essential for independent living among elderly people. No study has investigated motor performance in various cognitive-motor DT activities, utilizing the Timed Up and Go (TUG) test. This study aimed to compare motor performance between four cognitive-motor DT tests in community-dwelling older adults. The sample consisted of 60 older women. The cognitive tasks performed with the TUG test were (a) mental calculation, (b) memory recall, (c) verbal fluency, and (d) reaction to a stimulus. Lower limb muscle strength was assessed with the 30-Second Chair Stand Test, balance with the Four Square Step Test, and balance confidence with the Activities-specific Balance Confidence Scale. Completion times and DT costs were calculated. Mental calculation (r = 0.63, p < 0.01) and verbal fluency (r = 0.65, p < 0.01) tasks were similarly correlated with the TUG test, and significantly impacted motor performance compared to other DT tests. The reaction to a stimulus test showed a high relationship with the TUG test (r = 0.89, p < 0.01) and had the least impact on motor performance. These findings suggest that the cognitive task type can significantly influence motor performance during DT activities. Adding a cognitive load to the TUG test may improve its ability to identify older adults at risk for falls, aiding in the development of targeted interventions. Further research is required to validate these findings. [ABSTRACT FROM AUTHOR]

Performing mathematical calculations is a cognitive activity that can affect biological signals. This study aims to examine the changes in electroencephalogram (EEG) and electrocardiogram (ECG) signals of 36 healthy subjects during the performance of arithmetic tasks. To process EEG signals in different frequency bands, the energy and entropy of entropy (EoE) were extracted from the power spectrum and phase spectrum, respectively. Statistical analysis was conducted to determine meaningful features. These features were sent into support vector machine (SVM) and multi-layer perception (MLP) classifiers to assess their capability in separating math and rest classes. Results indicated the highest classification accuracy of 98.4% for classifying good counters in math and rest state using the MLP method. Based on the majority of features selected for each EEG channel, discriminative brain areas were identified. Analyzing EEG signals proved that math calculation may have multiple influences on various parts of the brain. By comparing good counters' brain activities to those in a resting state, prominent changes were observed in the F4, C4, T4, T5, P3, and O2 areas. However, O1 and O2 channels showed significant changes in the brain of bad counters compared to the resting state. Considering ECG signals also demonstrated that during math calculation the number of heart rates per minute surpasses the rest state. These alterations can occur due to cognitive abilities or emotional processes which were observed to be prominent in subjects who performed more accurate calculations. [ABSTRACT FROM AUTHOR]

Eye tracking technology is a high-potential tool for different mathematic cognition research areas. Moreover, there is a dire need for more studies that provide detailed information on the quality of registered eye data. This study aimed to illustrate the applicability of eye tracking in the examination of mathematical cognition, focusing specifically on primary school students completing a computerized mental arithmetic task. Results suggested that the eye tracking device effectively captured high-quality eye movement data when primary school children engaged in this specific task. Furthermore, significant negative correlations have been found between task performance and number of eye fixations. Finally, eye movements distinctions between "Areas of Interest" have been found, indicating different visual tracking associated with different components of arithmetic calculations. This study underscores the extensive possibilities for future research employing eye tracking devices during computerized calculation tasks as assessment tools to explore the complex visual and cognitive processes. [ABSTRACT FROM AUTHOR]

Studies of the impact of brain injury on memory processes often focus on the quantity and episodic richness of those recollections. Here, we argue that the organization of one's recollections offers critical insights into the impact of brain injury on functional memory. It is well‐established in studies of word list memory that free recall of unrelated words exhibits a clear temporal organization. This temporal contiguity effect refers to the fact that the order in which word lists are recalled reflects the original presentation order. Little is known, however, about the organization of recall for semantically rich materials, nor how recall organization is impacted by hippocampal damage and memory impairment. The present research is the first study, to our knowledge, of temporal organization in semantically rich narratives in three groups: (1) Adults with bilateral hippocampal damage and severe declarative memory impairment, (2) adults with bilateral ventromedial prefrontal cortex (vmPFC) damage and no memory impairment, and (3) demographically matched non‐brain‐injured comparison participants. We find that although the narrative recall of adults with bilateral hippocampal damage reflected the temporal order in which those narratives were experienced above chance levels, their temporal contiguity effect was significantly attenuated relative to comparison groups. In contrast, individuals with vmPFC damage did not differ from non‐brain‐injured comparison participants in temporal contiguity. This pattern of group differences yields insights into the cognitive and neural systems that support the use of temporal organization in recall. These data provide evidence that the retrieval of temporal context in narrative recall is hippocampal‐dependent, whereas damage to the vmPFC does not impair the temporal organization of narrative recall. This evidence of limited but demonstrable organization of memory in participants with hippocampal damage and amnesia speaks to the power of narrative structures in supporting meaningfully organized recall despite memory impairment. [ABSTRACT FROM AUTHOR]

Urban and rural children have different levels of performance in arithmetic processing. This study investigated whether such a residence difference can be explained by phonological processing. A total of 1,501 Chinese primary school students from urban and rural areas were recruited to complete nine cognitive tasks: two in arithmetic performance (subtraction and multiplication), one in phonological processing (word rhyming), two in quantity processing (numerosity and number comparison), one in visuo-spatial processing (mental rotation), as well as a mathematical reasoning task (number-series completion) as a contrast with arithmetic processing and two general cognitive tasks (choice reaction time and Raven's progressive matrices). The results showed that Chinese urban children had superior performance in arithmetic, which was eliminated after controlling for phonological ability, but not after controlling for quantity or visuo-spatial performance or general cognitive factors. Urban children also showed better performance in mathematical reasoning than did rural children, but residence difference in mathematical reasoning was not eliminated by any of the cognitive factors. The above result suggests that phonological processing explains the relationship between residence and arithmetic performance. [ABSTRACT FROM AUTHOR]

Background: Identifying covert consciousness in intensive care unit (ICU) patients with coma and other disorders of consciousness (DoC) is crucial for treatment decisions, but sensitive low-cost bedside markers are missing. We investigated whether automated pupillometry combined with passive and active cognitive paradigms can detect residual consciousness in ICU patients with DoC. Methods: We prospectively enrolled clinically low-response or unresponsive patients with traumatic or nontraumatic DoC from ICUs of a tertiary referral center. Age-matched and sex-matched healthy volunteers served as controls. Patients were categorized into clinically unresponsive (coma or unresponsive wakefulness syndrome) or clinically low-responsive (minimally conscious state or better). Using automated pupillometry, we recorded pupillary dilation to passive (visual and auditory stimuli) and active (mental arithmetic) cognitive paradigms, with task-specific success criteria (e.g., ≥ 3 of 5 pupillary dilations on five consecutive mental arithmetic tasks). Results: We obtained 699 pupillometry recordings at 178 time points from 91 ICU patients with brain injury (mean age 60 ± 13.8 years, 31% women, and 49.5% nontraumatic brain injuries). Recordings were also obtained from 26 matched controls (59 ± 14.8 years, 38% women). Passive paradigms yielded limited distinctions between patients and controls. However, active paradigms enabled discrimination between different states of consciousness. With mental arithmetic of moderate complexity, ≥ 3 pupillary dilations were seen in 17.8% of clinically unresponsive patients and 50.0% of clinically low-responsive patients (odds ratio 4.56, 95% confidence interval 2.09–10.10; p < 0.001). In comparison, 76.9% healthy controls responded with ≥ 3 pupillary dilations (p = 0.028). Results remained consistent across sensitivity analyses using different thresholds for success. Spearman's rank analysis underscored the robust association between pupillary dilations during mental arithmetic and consciousness levels (rho = 1, p = 0.017). Notably, one behaviorally unresponsive patient demonstrated persistent command-following behavior 2 weeks before overt signs of awareness, suggesting prolonged cognitive motor dissociation. Conclusions: Automated pupillometry combined with mental arithmetic can identify cognitive efforts, and hence covert consciousness, in ICU patients with acute DoC. [ABSTRACT FROM AUTHOR]

Air Traffic Controllers' (ATCos) mental workload is likely to remain the specific greatest functional limitation on the capacity of the Air Traffic Management (ATM) system. Developing computational models to monitor mental workload and task complexity is essential for enabling ATCOs and ATM systems to adapt to varying task demands. Most methodologies have computed task complexity based on basic parameters such as air-traffic density; however, literature research has shown that it also depends on many other factors. In this paper, we present a study in which we explored the possibility of predicting task complexity and performance through mental workload measurements of participants performing an ATM task in an air-traffic control simulator. Our findings suggest that mental workload measurements better predict poor performance and high task complexity peaks than other established factors. This underscores their potential for research into how different ATM factors affect task complexity. Understanding the role and the weight of these factors in the overall task complexity confronted by ATCos constitutes one of the biggest challenges currently faced by the ATM sphere and would significantly contribute to the safety of our sky. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate current trends in research of math anxiety (MA) through bibliometric perspective. Three main clusters were formed based on author keywords: cognitive correlates (working memory, attention, numerical cognition, mental arithmetic), psychological factors and effects (self-concept and self-efficacy, motivation, confidence, attitudes), and educational context (PISA, measurement, gender differences, math achievement, math education, assessment). Analysis of the index keywords revealed somewhat different organization with two dominant clusters: the experimental cluster in which the most frequent are psychophysiological measures and terms and the correlational cluster in which the topics of MA psychosocial factors are most represented. The map of bibliographic coupling showed several relatively separated groups of authors with different focus in cited references. However, a map of co-citation of authors revealed closeness of these separated groups, with Beilock, S. L. and Ashcraft, M. H. by far the most-cited authors in this field. [ABSTRACT FROM AUTHOR]