Levels Of Task Difficulty Research Articles

Learning Clinical Skills Using Haptic vs. Phantom Head Dental Chair Simulators in Removal of Artificial Caries: Cluster-Randomized Trials with Two Cohorts' Cavity Preparation.

Dental task trainer simulators using haptics (virtual touch) offers a cost-effective method of teaching certain clinical skills. The purpose of this study is to evaluate students' performance in removing artificial caries after training with either a haptic dental chair simulator with virtual reality or a traditional dental chair simulator with a mannequin head. Cluster Randomized Controlled Trials in two cohorts, both Year 1 dental students. Students taught using traditional dental chair simulators were compared with students taught using haptic-based simulators on their ability to cut a cavity in a plastic tooth following training. Across both cohorts, there was no difference in the quality of cavity cut, though students' technique differed across the two simulator groups in some respects. No difference was seen across both cohorts in the quality of cavity cut for a simple preparation, though students in the haptic condition performed less well in the more demanding task. Moreover, students in the haptic group were also less likely to be perceived to be 'holding the instrument appropriately'. These findings suggest further investigation is needed into the differences in handling of instruments and level of clinical task difficulty between the simulators.

Cognitive Effort-Based Decision-Making Across Experimental and Daily Life Indices in Younger and Older Adults.

The study investigated whether cognitive effort decision-making measured via a neuroeconomic paradigm that manipulated framing (gain vs. loss outcomes), could predict daily life engagement in mentally demanding activities in both younger and older adults. Younger and older adult participants (N = 310) completed the Cognitive Effort Discounting paradigm (Cog-ED), under both gain and loss conditions, to provide an experimental index of cognitive effort costs for each participant in each framing condition. A subset of participants (N = 230) also completed a 7-day Ecological Momentary Assessment (EMA) protocol measuring engagement in mentally demanding daily life activities. In a large, online sample, we replicated a robust increase in cognitive effort costs among older, relative to younger, adults. Additionally, costs were found to be reduced in the loss relative to gain frame, although these effects were only reliable at high levels of task difficulty and were not moderated by age. Critically, participants who had lower effort costs in the gain frame tended to report engaging in more mentally demanding daily life activities, but the opposite pattern was observed in the loss frame. Further analyses demonstrated the specificity of reward-related cognitive motivation in predicting daily life mentally demanding activities. Together, these results suggest that cognitive effort costs, as measured through behavioral choice patterns in a neuroeconomic decision-making task, can be used to predict and explain engagement in mentally demanding activities during daily life among both older and younger adults.

The Effect of Listening Task Complexity and Offline Learning on Postural Control

Background and Aims Postural control of the kinetic variable of motion plays an essential role in maintaining stability in daily activities. Dual tasks for studying balance or postural control are accompanied by cognitive tasks. The aim of the present study was to investigate the effect of listening task complexity and offline learning on postural control. Methods Twenty-eight employees with an age range of 30-40 years from Alzahra University of Tehran (PBUH) were selected by available sampling and based on inclusion criteria and divided into three groups with different training distributions of 2 minutes, 15 minutes, and 24 hours with three levels of difficulty (easy, medium, and difficult). Each group performed three blocks of six attempts with each attempt time of 35 seconds, the interval between attempts of 20 seconds, and the time interval between blocks depending on the division of the group: 2 minutes, 15 minutes, and 24 hours with three difficulty levels. Findings were analyzed using a combined factor analysis of variance with repeated measures of three groups (mass, 15 minutes, and 24 hours) and three task levels (easy, moderate, and difficult) and the Bonferroni post hoc test. Results Findings showed that the main effect of homework difficulty level and practice distribution was significant (P=0.001) and in the retention stage, there was a significant difference between the mean frequency power in the anterior-posterior direction in the low difficulty listening group and the high difficulty listening group. In the listening task, the interactive effect of task difficulty level in the distribution of practice was not significant. In the memorization stage, regarding the COP components (average frequency power in the anterior-posterior direction), the training group (24 hours), and in the listening task with an easy complexity level, the best condition was posture control, and in the training group (2 minutes) and in the listening task with difficult complexity level, the weakest condition was control posture. In the listening task with a high level of difficulty, the 24 hour training group had better average COP components than the mass training group and the 15 minute training group. Conclusion It seems that distance training over mass training along with the parameters of strengthening motor memory increases cognitive effort and motivation. According to Hacken, Kelso, and Bondes hypothesis (progress-regression), educators should include homework in teaching instruction and from simple to difficult in the curriculum.

The protective effect of educational level varies as a function of the difficulty of the memory task in ageing.

The online version contains supplementary material available at 10.1007/s10433-022-00724-z.

English as a Foreign Language Teachers’ Perceptions of Their Self-Efficacy in Using Instructional Strategies

<p style="text-align: justify;">This investigation examined English as a foreign language (EFL) teachers’ perceptions of their self-efficacy in using instructional strategies in the context of the Mekong Delta of Vietnam. The research was designed as a descriptive research collecting quantitative and qualitative data from a questionnaire and semi-structured interviews. Forty-six Vietnamese EFL teachers were invited to partake in the study. The results indicated that participants were in general confident in using instructional strategies in their English classes. Specifically, the participants were highly confident in their abilities to use multimedia (M=4.41), assessment techniques (M=4.35), and classroom English (M=4.35). The study also indicated that participants were not confident in evaluating the level of task difficulty (M=3.37), dealing with unmotivated students (M=3.57), and meeting students’ particular needs for support (M=3.62). Pedagogical implications and recommendations were addressed to help manifold stakeholders at the end of this paper.</p>

Measuring Cognitive Workload Using Multimodal Sensors.

This study aims to identify a set of indicators to estimate cognitive workload using a multimodal sensing approach and machine learning. A set of three cognitive tests were conducted to induce cognitive workload in twelve participants at two levels of task difficulty (Easy and Hard). Four sensors were used to measure the participants' physiological change, including, Electrocardiogram (ECG), electrodermal activity (EDA), respiration (RESP), and blood oxygen saturation (SpO2). To understand the perceived cognitive workload, NASA-TLX was used after each test and analysed using Chi-Square test. Three well-know classifiers (LDA, SVM, and DT) were trained and tested independently using the physiological data. The statistical analysis showed that participants' perceived cognitive workload was significantly different ( ) between the tests, which demonstrated the validity of the experimental conditions to induce different cognitive levels. Classification results showed that a fusion of ECG and EDA presented good discriminating power (acc = 0.74) for cognitive workload detection. This study provides preliminary results in the identification of a possible set of indicators of cognitive workload. Future work needs to be carried out to validate the indicators using more realistic scenarios and with a larger population.

Age- and Episodic Memory-related Differences in Task-based Functional Connectivity in Women and Men.

Aging is associated with episodic memory decline and changes in functional brain connectivity. Understanding whether and how biological sex influences age- and memory performance-related functional connectivity has important theoretical implications for the cognitive neuroscience of memory and aging. Here, we scanned 161 healthy adults between 19 and 76 years of age in an event-related fMRI study of face-location spatial context memory. Adults were scanned while performing easy and difficult versions of the task at both encoding and retrieval. We used multivariate whole-brain partial least squares connectivity to test the hypothesis that there are sex differences in age- and episodic memory performance-related functional connectivity. We examined how individual differences in age and retrieval accuracy correlated with task-related connectivity. We then repeated this analysis after disaggregating the data by self-reported sex. We found that increased encoding and retrieval-related connectivity within the dorsal attention network (DAN), and between DAN and frontoparietal network and visual networks, were positively correlated to retrieval accuracy and negatively correlated with age in both sexes. We also observed sex differences in age- and performance-related functional connectivity: (a) Greater between-networks integration was apparent at both levels of task difficulty in women only, and (b) increased DAN-default mode network connectivity with age was observed in men and was correlated with poorer memory performance. Therefore, the neural correlates of age-related episodic memory decline differ in women and men and have important theoretical and clinical implications for the cognitive neuroscience of memory, aging, and dementia prevention.

The Effect of Modification Psychomotor Tasks in the Virtual Reality on Cadence and Behavioural Responses of Cycling

Virtual reality is an alternative tool to provide a safe and competitive environment, especially for training and competitions. This study aims to evaluate the effects of modified psychomotor tasks in the virtual reality on the alpha/beta ratio, power output, heart rate, and cadence. The participants are recruited among national development cyclists from National Sport School. The environment of virtual reality was modified from the available virtual reality TACX smart trainer system. The one-way multivariate of variance (MANOVA) identified the effects of the five different levels of psychomotor task (independent variables) in virtual reality on multiple variables of physiological responses. The MANOVA results indicate a statistically significant multivariate main effect for the five levels of task difficulty in road cycling, when jointly considering on the variables of alpha/beta ratio, power output, heart rate, and cadence. The multivariate general linear model for univariate ANOVA results demonstrates a significant difference between subject on alpha/beta ratio and cadence. Significant task pairwise differences were obtained for cadence between Task 1 and both Tasks 2 and 5. The results suggest human's interaction with virtual reality, specifically during the psychomotor task during road cycling. The significant effects on the joint physiological responses ensured that evaluation of the experiment on developed task difficulty in virtual reality was practical, applicable and can be modified when required for training or assessment. The involvement of cognitive functions in response to behavioural mechanism merits further investigation and are deferred for future work.

Cognitive performance and electroencephalographic variations in air traffic controllers under various mental workload and time of day

The aim of this study was to investigate the effects of mental workload (MWL) and time of day on cognitive performance and electroencephalographic (EEG) parameters of air traffic controllers. EEG signals recorded while 20 professional air traffic controllers performed cognitive tasks [A-X Continuous Performance Test (AX-CPT) and 3-back working memory task] after they were exposed to two levels of task difficulty (high and low MWL) in the morning and afternoon. Significant decreases in cognitive performance were found when the levels of task difficulty increased in both tasks. The results confirmed the sensitivity of the theta and beta activities to levels of task difficulty in the 3-back task, while they were not affected in the AX-CPT. Theta and beta activities were influenced by time of day in the AX-CPT. The findings provide guidance for application of changes in EEG parameters when MWL level is manipulated during the day that could be implemented in future for the development of real-time monitoring systems to improve aviation safety.

Differential relationships between mathematics self-efficacy and national test performance according to perceived task difficulty

ABSTRACT We explore the effect of students’ perceived task difficulty on the mathematics self-efficacy – performance relationship. Specifically, we expand on previous reciprocal effects studies through including students’ self-efficacy for different levels of task difficulty in an empirical investigation. We examined students’ self-efficacy for easy, medium difficulty, and hard tasks and performance on a national mathematics test in a longitudinal study of 95 Norwegian students from grade 8 to grade 9. We found differential relationships between self-efficacy for different levels of task difficulty and national test performance. In support of the ‘skill development’ model, grade 8 national test performance predicted grade 9 self-efficacy for medium and hard, but not easy, tasks. While mastery experiences are likely to arise more easily on easier tasks, such experiences are likely to matter more on harder tasks. Our findings highlight the importance of supporting students’ engagement with challenging tasks to strengthen both their performance and self-efficacy.

Effect of individualized cognitive and postural task difficulty levels on postural control during dual task condition

BackgroundPrevious dual task studies suggested that the difficulty of the concurrent cognitive and motor tasks may not be challenging to the same degree for each person. This study approaches this problem by setting individualized difficulty levels for tasks to examine the dual task interference. Research questionDo the features of postural sway depend on increased individualized difficulty levels of concurrent cognitive and postural activities? Methods20 young healthy participants (10 male, 10 female) took part in the study. Before the experiments, cognitive task difficulty (No-, Medium-, High) has been set individually. Subjects performed postural tasks (quiet stance, voluntary sway) concurrently with or without a cognitive task which based on simple arithmetic calculations. Postural sway features were examined. ResultsPostural sway features were affected by individualized difficulty level of concurrent cognitive and postural activities. In voluntary sway, as a more challenging postural task, higher reductions were observed for such sway features as COP velocity and range in AP direction. SignificanceThis study signaled task-specific changes in postural sway features. When the difficulty levels were set individually, the effect of motor and cognitive dual task was more apparent when the balance requirement of the primary motor task increased.

Evaluation of drivers' mental workload based on multi-modal physiological signals

Accurately assessing the driver's mental workload is of great significance to reduce the traffic accidents caused by the driver's mental overload. This study aims to evaluate drivers' mental workload in simulated typical driving scenarios, with <italic>N</italic>-back cognitive tasks used to manipulate varied levels of task difficulty. We collect data on multi-modal physiological signals including electroencephalogram (EEG), electrocardiogram (ECG), and electrodermal activity (EDA) signals, and subjective mental load of the National Aeronautics and Space Administration task load index (NASA_TLX) during the task completion process of the driver in the experiment, and propose a series of mental workload classification models based on feature analysis and pattern recognition of the multi-modal physiological signals. These classification models are verified by machine learning algorithms of random forest, decision tree and <italic>k</italic>-nearest neighbor models. The results show that the accuracy of classification models varies with different modalities of physiological signals. EEG-based classification models yield the highest accuracy among single-modal classification models, followed by EDA-based and ECG-based models. Multi-modal-based classification models generally perform better than single-modal classification models. The random forest classification algorithm based on three-modal physiological signals of EEG, ECG and EDA has the highest classification accuracy.

Effect of Arm Movement and Task Difficulty on Balance Performance in Children, Adolescents, and Young Adults

BackgroundStudies have shown that restricted compared to free arm movement negatively affects balance performance during balance assessment and this is reinforced when the level of task difficulty (e.g., varying stance/walk conditions, sensory manipulations) is increased. However, it remains unclear whether these findings apply to individuals with differences in the development of the postural control system. Thus, we examined the influence of arm movement and task difficulty on balance performance in children, adolescents, and young adults.MethodsStatic, dynamic, and proactive balance performance were assessed in 40 children (11.5 ± 0.6 years), 30 adolescents (14.0 ± 1.1 years), and 41 young adults (24.7 ± 3.0 years) using the same standardized balance tests [i.e., one-legged stance (OLS) time with eyes opened/closed and/or on firm/foam ground, 3-m beam (width: 6, 4.5, or 3 cm) walking backward step number, Lower Quarter Y-Balance test (YBT-LQ) reach distance] with various difficulty levels under free vs. restricted arm movement conditions.ResultsIn all but one test, balance performance was significantly better during free compared to restricted arm movement. Arm by age interactions were only observed for the YBT-LQ and post hoc analyses revealed significantly greater performance differences between free and restricted arm movement, especially, in young adults. Arm by age by task difficulty interactions were found for the OLS and the 3-m beam walking backward test. Post hoc analyses showed significantly greater performance differences between free and restricted arm movement during high vs. low levels of task difficulty and this was more pronounced in children and adolescents.ConclusionsRegardless of age, static, dynamic, and proactive balance performance benefited from arm movements and this was especially noted for youth performing difficult balance tasks.

Effects of degraded speech processing and binaural unmasking investigated using functional near-infrared spectroscopy (fNIRS).

The present study aimed to investigate the effects of degraded speech perception and binaural unmasking using functional near-infrared spectroscopy (fNIRS). Normal hearing listeners were tested when attending to unprocessed or vocoded speech, presented to the left ear at two speech-to-noise ratios (SNRs). Additionally, by comparing monaural versus diotic masker noise, we measured binaural unmasking. Our primary research question was whether the prefrontal cortex and temporal cortex responded differently to varying listening configurations. Our a priori regions of interest (ROIs) were located at the left dorsolateral prefrontal cortex (DLPFC) and auditory cortex (AC). The left DLPFC has been reported to be involved in attentional processes when listening to degraded speech and in spatial hearing processing, while the AC has been reported to be sensitive to speech intelligibility. Comparisons of cortical activity between these two ROIs revealed significantly different fNIRS response patterns. Further, we showed a significant and positive correlation between self-reported task difficulty levels and fNIRS responses in the DLPFC, with a negative but non-significant correlation for the left AC, suggesting that the two ROIs played different roles in effortful speech perception. Our secondary question was whether activity within three sub-regions of the lateral PFC (LPFC) including the DLPFC was differentially affected by varying speech-noise configurations. We found significant effects of spectral degradation and SNR, and significant differences in fNIRS response amplitudes between the three regions, but no significant interaction between ROI and speech type, or between ROI and SNR. When attending to speech with monaural and diotic noises, participants reported the latter conditions being easier; however, no significant main effect of masker condition on cortical activity was observed. For cortical responses in the LPFC, a significant interaction between SNR and masker condition was observed. These findings suggest that binaural unmasking affects cortical activity through improving speech reception threshold in noise, rather than by reducing effort exerted.

The effect of mental schema evolution on mental workload measurement: an EEG study with simulated quadrotor UAV operation

Objective. Mental workload is the result of the interactions between the demands of an operation task, the environment in which the task is performed, and the skills, behavior and perception of the performer. Working under a high mental workload can significantly affect an operator’s ability to choose optimal decisions, judgments and motor actions while operating an unmanned aerial vehicle (UAV). However, the effect of mental schema, which reflects the level of expertise of an operator, on mental workload remains unclear. Here, we propose a theoretical framework for describing how the evolution of mental schema affects mental workload from the perspective of cognitive processing. Approach. We recruited 51 students to participate in a 10-day simulated quadrotor UAV flight training exercise. The EEG power spectral density (PSD)-based metrics were used to investigate the changes in neural responses caused by variations in the mental workload at different stages of mental schema evolution. Main results. It was found that the mental schema evolution influenced the direction and change trends of the frontal theta PSD, parietal alpha PSD, and central beta PSD, which are EEG indicators of mental workload. Initially, before the mental schema was formed, only the frontal theta PSD increased with increasing task difficulty; when the mental schema was initially being developed, the frontal theta PSD and the parietal alpha PSD decreased with increasing task difficulty, while the central beta PSD increased with increasing task difficulty. Finally, as the mental schema gradually matured, the trend of the three indicators did not change with increasing task difficulty. However, differences in the frontal PSD became more pronounced across task difficulty levels, while differences in the parietal PSD narrowed. Significance. Our results describe the relationship between the EEG PSD and the mental workload of UAV operators as the mental schema evolved. This suggests that EEG activity can be used to identify the mental schema and mental workload experienced by operators while performing a task, which can not only provide more accurate measurements of mental workload but also provide insights into the development of an operator’s skill level.

Effects of Noninvasive Cervical Vagal Nerve Stimulation on Cognitive Performance But Not Brain Activation in Healthy Adults

ObjectivesWhile preliminary evidence suggests that noninvasive vagal nerve stimulation (nVNS) may enhance cognition, to our knowledge, no study has directly assessed the effects of nVNS on brain function and cognitive performance in healthy individuals. The aim of this study was therefore to assess whether nVNS enhances complex visuospatial problem solving in a normative sample. Functional magnetic resonance imaging (fMRI) was used to examine underlying neural substrates. Material and MethodsParticipants received transcutaneous cervical nVNS (N = 15) or sham (N = 15) stimulation during a 3 T fMRI scan. Stimulation lasted for 2 min at 24 V for nVNS and at 4.5 V for sham. Subjects completed a matrix reasoning (MR) task in the scanner and a forced-choice recognition task outside the scanner. An analysis of variance (ANOVA) was used to assess group differences in cognitive performance. And linear mixed effects (LMEs) regression analysis was used to assess main and interaction effects of experimental groups, level of MR task difficulty, and recall accuracy on changes in blood oxygen level-dependent (BOLD) signal. ResultsSubjects who received nVNS showed higher accuracy for both easy (p = 0.017) and hard (p = 0.013) items of the MR task, slower reaction times for hard items (p = 0.014), and fewer false negative errors during the forced-choice recognition task (p = 0.047). MR task difficulty related to increased activation in frontoparietal regions (p < 0.001). No difference between nVNS and sham stimulation was found on BOLD response during performance of the MR task. ConclusionsWe hypothesize that nVNS increased attention compared to sham, and that this effect led to enhanced executive functions, and consequently to better performance on visuospatial reasoning and recognition tasks. Results provide initial support that nVNS may be a low-risk, low-cost treatment for cognitive disorders.

Pediatric speech understanding in noise and the role of working memory andcomprehension

Working memory is vital to a child’s cognitive processing and speech understanding in noise. More recent findings suggest that the relationship between speech recognition in noise and auditory comprehension may be capturing difficulties in understanding speech in noise which have been linked to cognitive and linguistic skills. Children’s auditory-cognitive performance is highly sensitive to processing load. The extent that children engage cognitive resources depends on demands of task difficulty and intensity level of four-talker babble. The combined costs of performing a difficult task in adverse acoustical conditions are greater than the sum of the individual costs. This suggest that the relationship between speech recognition in noise and auditory comprehension may be capturing difficulties in language which may have effects in academic success. Data will be presented (1) show that audibility alone does not account for difficulties in speech perception in noise (2) showing the complex relationship between working memory and auditory comprehension. (3) Implications for clinical speech in noise screener for children. While app-based interventions for speech and language exist, to our knowledge, none explicitly screen for perception of speech in the presence of noise.

과제 난이도에 따른 연속적인 조준 동작의 제어 특성

The present study investigated characteristics on the control of continuous aiming movements in index of difficulty (i.e., task difficulty). In this study, 39 participants were instructed to perform continuous aiming movement to specified targets across three task difficulty (i.e., low accuracy, normal accuracy, and high accuracy constraints). The characteristics of the movement speed in performing the continuous aiming motion according to the three task difficulty levels were collected. The results showed that the movement speed was the slowest in the high task difficulty level, and the movement pattern fluctuation was the largest. On the other hand, the movement performance speed was the fastest in the low task difficulty level, and the movement pattern fluctuations were also the smallest. These results suggest that as the task difficulty increases, it is difficult to control the muscle torque of the limbs in performing continuous aiming movements. In addition, it is shown that the higher the task difficulty, the lower the movement speed in order to increase the accuracy of the movement in performing continuous aiming movements.

Comparability of difficulty levels of translation tasks in CET-6 parallel test forms: evidence from product and process-based data

ABSTRACT This study investigates the comparability of three parallel translation tasks selected from a College English Test Band-6 (CET-6) and explores the major linguistic features contributing to translation difficulty. Data obtained from the participants’ subjective rating, eye-tracking, and performance evaluation were triangulated to measure the comparability of difficulty levels of parallel translation tasks. Data of word translation entropy, translation errors, and participants’ retrospective reports were correlated to examine the difficulty triggers. The results show that: (i) the text comparability was evidenced by eye-tracking indicators and performance measurements, but not supported by subjective ratings; (ii) the domain content words (DCWs) were reported by the participants as the major cause of translation difficulties and the unequal number of DCWs among the three tasks led to inconsistent ratings for the task difficulty. Our findings suggest that test-takers’ subjective perception and their cognitive skills deserve serious consideration by test designers, as these two factors can better demonstrate difficulty levels among parallel tasks. Our study postulates a new direction to establish a relationship between task characteristics and test validity, and provides suggestions for the CET-6 committee and other examination boards with practical methods to be able to compare the difficulty levels of parallel translation tasks.

The Relationship between Self-Efficiency and Mathematical Knowledge of 3-D Shapes of Fifth Grade of Elementary School

This study aims to determine the relationship between self-efficacy and mathematical knowledge of 3-D shapes of fifth graders of elementary school. Participants in this study were 76 fifth grade students from a public school in Duri region, Indonesia. The method used in this research is the correlation and regression study. Instruments in this study are non-test and test. The non-test instrument is in the form of a questionnaire, and the test instrument is in the form of questions regarding the 3-D shapes. The indicators of self-efficacy consist of magnitude (level of task difficulty), strength (strength of belief) and generality, while the indicators of mathematical knowledge of 3-D shapes are properties, area, and volume of cubes and rectangular prism. The data analysis technique was carried out by presenting data, normality test, linearity test, linear regression test, and hypothesis testing using Pearson's product moment correlation. The results show that there is a significant positive relationship between students’ self-efficacy and mathematical knowledge of 3-D shapes.