Changes In Cognitive Load Research Articles

Sensitivity evaluation of the visual, tactile, and auditory detection response task method while driving

ABSTRACTObjectives: In this article, we evaluate the sensitivity to cognitive load of 3 versions of the Detection Response Task method (DRT), proposed in ISO Draft Standard DIS-17488.Methods: We present a user study with 30 participants in which we compared the sensitivity to cognitive load of visual, audio, and tactile DRT in a simulated driving environment. The amount of cognitive load was manipulated with secondary n-back tasks at 2 levels of difficulty (0-back and 1-back). We also explored whether the DRT method is least sensitive to cognitive load when the stimuli and secondary task are of the same modality. For this purpose, we used 3 forms to present the n-back task stimuli: visual, audio, and tactile. Responses to the task were always vocal. The experiment was based on a between-subject design (the DRT modalities) with 2 levels of within-subject design study (modalities and difficulty of the secondary n-back tasks). The participants' primary task in the study was to drive safely, and a second priority was to answer to DRT stimuli and perform secondary tasks.Results: The results indicate that all 3 versions of the DRT tested were sensitive to detecting the difference in cognitive load between the reference driving period and driving and engaging in the secondary tasks. Only the visual DRT discriminated between the 0-back and 1-back conditions on mean response time. Contrary to expectations, no interaction was observed between DRT modality and the stimuli modality used for presentation of the secondary tasks.Conclusions: None of the 3 methods of presenting DRT stimuli showed a consistent advantage in sensitivity in differentiating multiple levels of cognitive load if all response times, hit rates, and secondary task performance are considered. If only response time is considered, the visual presentation of the DRT stimulus used in this study showed some advantages. In interpreting these data, it should be noted that the methods of DRT stimulus presentation varied somewhat from the currently proposed draft ISO standard and it is possible that the relative salience level of the visual DRT stimulus influenced the findings. It is further suggested that more than 2 levels of difficulty of the n-back task should be considered for further investigation of the relative sensitivity of different DRT stimuli modalities. Parameters that indicate change in cognitive load (response time, hit rate, task performance) should be analyzed together in assessing the overall impact on the driver and not individually, in order to obtain a fuller insight of the assessed cognitive load.

A simulator evaluation of effects of assistive technologies on driver cognitive load at railway-level crossings

ABSTRACTIntelligent Transport Systems (ITS) have the potential to substantially reduce the number of crashes caused by human errors at railway-level crossings. However, such systems could overwhelm drivers, generate different types of driver errors, and have negative effects on safety at level crossing. The literature shows an increasing interest for new ITS for increasing driver situational awareness at level crossings, as well as evaluations of such new systems on compliance. To the authors' knowledge, the potential negative effects of such technologies have not yet been comprehensively evaluated. This study aimed at assessing the effect of different ITS interventions, designed to enhance driver behavior at railway crossings, on driver's cognitive loads. Fifty-eight participants took part in a driving simulator study in which three ITS devices were tested: an in-vehicle visual ITS, an in-vehicle audio ITS, and an on-road valet system. Driver cognitive load was objectively and subjectively assessed for each ITS intervention. Objective data were collected from a heart rate (HR) monitor and an eye tracker, whereas subjective data was collected with the NASA Task Load Index (NASA-TLX) questionnaire. Overall, results indicated that the three trialed technologies did not result in significant changes in cognitive load while approaching crossings.

Sociotechnical Human Factors Involved in Remote Online Usability Testing of Two eHealth Interventions.

BackgroundResearch in the fields of human performance technology and human computer interaction are challenging the traditional macro focus of usability testing arguing for methods that help test moderators assess “use in context” (ie, cognitive skills, usability understood over time) and in authentic “real world” settings. Human factors in these complex test scenarios may impact on the quality of usability results being derived yet there is a lack of research detailing moderator experiences in these test environments. Most comparative research has focused on the impact of the physical environment on results, and rarely on how the sociotechnical elements of the test environment affect moderator and test user performance. Improving our understanding of moderator roles and experiences with conducting “real world” usability testing can lead to improved techniques and strategiesObjectiveTo understand moderator experiences of using Web-conferencing software to conduct remote usability testing of 2 eHealth interventions.MethodsAn exploratory case study approach was used to study 4 moderators’ experiences using Blackboard Collaborate for remote testing sessions of 2 different eHealth interventions. Data collection involved audio-recording iterative cycles of test sessions, collecting summary notes taken by moderators, and conducting 2 90-minute focus groups via teleconference. A direct content analysis with an inductive coding approach was used to explore personal accounts, assess the credibility of data interpretation, and generate consensus on the thematic structure of the results.ResultsFollowing the convergence of data from the various sources, 3 major themes were identified: (1) moderators experienced and adapted to unpredictable changes in cognitive load during testing; (2) moderators experienced challenges in creating and sustaining social presence and untangling dialogue; and (3) moderators experienced diverse technical demands, but were able to collaboratively troubleshoot with test users.ConclusionsResults highlight important human-computer interactions and human factor qualities that impact usability testing processes. Moderators need an advanced skill and knowledge set to address the social interaction aspects of Web-based usability testing and technical aspects of conferencing software during test sessions. Findings from moderator-focused studies can inform the design of remote testing platforms and real-time usability evaluation processes that place less cognitive burden on moderators and test users.

Cognitive Load Changes in Pre-Service Teachers with Computational Thinking Education

Since the emphasis of utilizing ICT in education moves from ICT to Computing in many countries, curriculums adapt the Computational Thinking (CT) teaching as a basic courses not only for primary school but also to CS education. Even though the depth of CT teaching may be different, we may expect similar impact of CT teaching results to student problem solving skills. With this rationale, we opened designed CT based education program for freshman introductory of computer application course. Developed course consists of 10 class hours program and the effectiveness of designed programs have been tested, firstly for improving CT capabilities of learners in problem solving environment, and secondarily the cognitive load changes appeared in the problem solving process have been measured with direct brain wave measurement of EEG while solving problems. The test results showed that designed CT program affected to the improvement of problem solving skill, and also show the tendency of decrease in cognitive overload in the experimental group.

Measuring cognitive load: performance, mental effort and simulation task complexity.

Interest in applying cognitive load theory in health care simulation is growing. This line of inquiry requires measures that are sensitive to changes in cognitive load arising from different instructional designs. Recently, mental effort ratings and secondary task performance have shown promise as measures of cognitive load in health care simulation. We investigate the sensitivity of these measures to predicted differences in intrinsic load arising from variations in task complexity and learner expertise during simulation-based surgical skills training. We randomly assigned 28 novice medical students to simulation training on a simple or complex surgical knot-tying task. Participants completed 13 practice trials, interspersed with computer-based video instruction. On trials 1, 5, 9 and 13, knot-tying performance was assessed using time and movement efficiency measures, and cognitive load was assessed using subjective rating of mental effort (SRME) and simple reaction time (SRT) on a vibrotactile stimulus-monitoring secondary task. Significant improvements in knot-tying performance (F(1.04,24.95) =41.1, p<0.001 for movements; F(1.04,25.90) =49.9, p<0.001 for time) and reduced cognitive load (F(2.3,58.5) =57.7, p<0.001 for SRME; F(1.8,47.3) =10.5, p<0.001 for SRT) were observed in both groups during training. The simple-task group demonstrated superior knot tying (F(1,24) =5.2, p=0.031 for movements; F(1,24) =6.5, p=0.017 for time) and a faster decline in SRME over the first five trials (F(1,26) = 6.45, p=0.017) compared with their peers. Although SRT followed a similar pattern, group differences were not statistically significant. Both secondary task performance and mental effort ratings are sensitive to changes in intrinsic load among novices engaged in simulation-based learning. These measures can be used to track cognitive load during skills training. Mental effort ratings are also sensitive to small differences in intrinsic load arising from variations in the physical complexity of a simulation task. The complementary nature of these subjective and objective measures suggests their combined use is advantageous in simulation instructional design research.

Cognitive processing load during listening is reduced more by decreasing voice similarity than by increasing spatial separation between target and masker speech.

We investigated changes in speech recognition and cognitive processing load due to the masking release attributable to decreasing similarity between target and masker speech. This was achieved by using masker voices with either the same (female) gender as the target speech or different gender (male) and/or by spatially separating the target and masker speech using HRTFs. We assessed the relation between the signal-to-noise ratio required for 50% sentence intelligibility, the pupil response and cognitive abilities. We hypothesized that the pupil response, a measure of cognitive processing load, would be larger for co-located maskers and for same-gender compared to different-gender maskers. We further expected that better cognitive abilities would be associated with better speech perception and larger pupil responses as the allocation of larger capacity may result in more intense mental processing. In line with previous studies, the performance benefit from different-gender compared to same-gender maskers was larger for co-located masker signals. The performance benefit of spatially-separated maskers was larger for same-gender maskers. The pupil response was larger for same-gender than for different-gender maskers, but was not reduced by spatial separation. We observed associations between better perception performance and better working memory, better information updating, and better executive abilities when applying no corrections for multiple comparisons. The pupil response was not associated with cognitive abilities. Thus, although both gender and location differences between target and masker facilitate speech perception, only gender differences lower cognitive processing load. Presenting a more dissimilar masker may facilitate target-masker separation at a later (cognitive) processing stage than increasing the spatial separation between the target and masker. The pupil response provides information about speech perception that complements intelligibility data.

Measuring Load on Working Memory: The Use of Heart Rate as a Means of Measuring Chemistry Students’ Cognitive Load

Information processing provides a powerful model for understanding how learning occurs and highlights the important role that cognitive load plays in this process. In instances in which the cognitive load of a problem exceeds the available working memory, learning can be seriously hindered. Previously reported methods for measuring cognitive load have typically been collected posthoc and can be subjective. More recent methods, however, rely on the collection of physiological data such as blink rate, heat flow, galvanic skin response, or heart rate; these methods address many of the shortcomings associated with more traditional techniques. This manuscript presents our attempts to validate the use of heart rate as a means of measuring changes in cognitive load in chemistry students and faculty.

Nonlinear dynamical structure of sway path during standing in patients with multiple sclerosis and in healthy controls is affected by changes in sensory input and cognitive load

Although several studies have applied traditional linear measures to evaluate postural control of patients with multiple sclerosis (MS), little is known about the nonlinear dynamics of this patient group. In this study, recurrence quantification analysis (RQA), a well documented nonlinear method, was used to compare the nonlinear dynamical structure of postural sway in two groups consisting of MS patients (n=23) and healthy matched controls (n=23). The study focuses on three levels of postural difficulty consisting of (1) standing on a rigid surface (force platform) with eyes open, (2) standing on a rigid surface with eyes closed, and (3) standing on a foam surface with eyes closed. The two levels of cognitive difficulty measured, consisted of a single postural task and a dual postural–cognitive task. It was observed that as the postural conditions became more difficult, the center of pressure (COP) time series of both groups became less regular as recorded in lower recurrence rate, less complex in deterministic structure as reflected in lower RQA entropy, and less nonstationary as reflected in the recording of lower Trend. Moreover, as cognitive conditions became more difficult, COP time series became less regular (lower %Rec in the anteroposterior direction and lower %Det in both directions), less complex in deterministic structure (lower RQA Ent in the anteroposterior direction), and less nonstationary (lower trend in the anteroposterior direction). The analytical results of the research show that there is a similar dynamical structure for both the MS patients and the control group; however, the nonlinear behavior of both groups was different under various experimental conditions.

Reduced but broader prefrontal activity in patients with schizophrenia during n-back working memory tasks: A multi-channel near-infrared spectroscopy study

BackgroundCaudal regions of the prefrontal cortex, including the dorsolateral (DLPFC) and ventrolateral (VLPFC) prefrontal cortex, are involved in essential cognitive functions such as working memory. In contrast, more rostral regions, such as the frontopolar cortex (FpC), have integrative functions among cognitive functions and thereby contribute crucially to real-world social activity. Previous functional magnetic resonance imaging studies have shown patients with schizophrenia had different DLPFC activity pattern in response to cognitive load changes compared to healthy controls; however, the spatial relationship between the caudal and rostral prefrontal activation has not been evaluated under less-constrained conditions. MethodTwenty-six patients with schizophrenia and 26 age-, sex-, and premorbid-intelligence-matched healthy controls participated in this study. Hemodynamic changes during n-back working memory tasks with different cognitive loads were measured using multi-channel near-infrared spectroscopy (NIRS). ResultsHealthy controls showed significant task-related activity in the bilateral VLPFC and significant task-related decreased activity in the DLPFC, with greater signal changes when the task required more cognitive load. In contrast, patients with schizophrenia showed activation in the more rostral regions, including bilateral DLPFC and FpC. Neither decreased activity nor greater activation in proportion to elevated cognitive load occurred. ConclusionsThis multi-channel NIRS study demonstrated that activation intensity did not increase in patients with schizophrenia associated with cognitive load changes, suggesting hypo-frontality as cognitive impairment in schizophrenia. On the other hand, patients had broader prefrontal activity in areas such as the bilateral DLPFC and FpC regions, thus suggesting a hyper-frontality compensatory response.

“Can waiting awaken the resting brain?” A comparison of waiting- and cognitive task-induced attenuation of very low frequency neural oscillations

The default mode network (DMN) is characterised by coherent very low frequency (VLF) neural oscillations in the resting brain. The attenuation of this activity has been demonstrated following the transition from rest to performance of a broad range of cognitive goal-directed tasks. Whether the activity of resting state VLF oscillations is attenuated during non-cognitive goal-directed tasks such as waiting for rewarding outcomes is not known. This study examined the VLF EEG power from resting to performance of attention demanding task and two types of goal-directed waiting tasks. The association between the attenuation of VLF EEG power and Attention-Deficit/Hyperactivity Disorder (ADHD) symptoms was examined. Direct current EEG (DC-EEG) data were collected from 32 healthy young adults (half high and half low ADHD symptom scorers) during (i) a rest state, (ii) while performing a cognitive demanding reaction time task (2CRT), and (iii) while undertaking each of two different goal-directed waiting conditions: “forced-to-wait (FW)” and “choose-to-wait (CW)” tasks. The spatial distribution of VLF EEG power across scalp was similar to that seen in previous resting VLF EEG studies. Significant rest-to-task attenuation of VLF EEG power occurred during the 2CRT and the CW task, but not during the FW task. The association between self-ratings of ADHD symptoms and waiting-induced attenuation was not significant. This study suggests VLF EEG power attenuation that occurs following rest-to-task transition is not simply determined by changes in cognitive load. The goal-directed nature of a task, its motivated nature and/or the involvement of effortful attention may also contribute. Future studies should explore the attenuation of resting state VLF oscillations during waiting and impulsive choice.

Redefining Media Content and Structure in Terms of Available Resources

This study reconceptualizes redundancy, complexity, and emotion in terms of cognitive load (specifically as resources allocated and required), then measures the combined real-time impact of these variables on available resources and encoding over the course of an hour television news program. Operational definitions of redundancy in the literature were ordered by their theoretically predicted level of resources required, then coded overtime. Dynamic measures of audio and video complexity in terms of resources allocated and required were developed and tested. Over the course of the news program, all combinations of independent variables occurred and the theoretically derived combinations of cognitive load successfully predicted changes in resources available as measured by Secondary Task Reaction Times (STRTs) and encoding indexed by recognition. The results suggest that defining message variables in terms of dynamic changes in cognitive load can allow us to predict the simultaneous dynamic impact of multiple message variables which contribute to complexity on processing capacity and message processing.

Automatic cognitive load evaluation using writing features: An exploratory study

Evaluating cognitive load is a key step in designing adaptive multimedia learning environments. However, there is still a lack of evaluation methods which can not only unobtrusively collect user data without supplement equipment but also objectively, quantitatively and in real time evaluate user cognitive load based on the data. This paper presents a new approach to evaluating cognitive load by combining writing features from free text and machine learning techniques. Specifically, changes in writing features are first investigated across three levels of cognitive load and the results offer some first insights for the potential of writing features to indicate cognitive load changes; further, a single feature is examined to detect which features are most predictive of cognitive load changes, and back-propagation neural networks, along with two feature selection methods, are trained to classify three cognitive load levels with 76.27% accuracy. These results show that writing features are useful for evaluating cognitive load when suitable classifiers are adopted. Relevance to industryThis study provides evidence that cognitive load can affect handwriting features, and also develops an automatic classification method of discriminating different levels of cognitive load on handwriting features using machine learning technologies. The findings can extend the use of handwritten devices and provide a new method for usability testing.

Pupil diameter measurement errors as a function of gaze direction in corneal reflection eyetrackers

Pupil dilation is a useful, noninvasive technique for measuring the change in cognitive load. Since it is implicit and nonverbal, it is particularly useful with preverbal or nonverbal participants. In cognitive psychology, pupil dilation is most often measured by corneal reflection eye-tracking devices. The present study investigates the effect of gaze position on pupil size estimation by three common eye-tracking systems. The task consisted of a simple object pursuit situation, as a sphere rotated around the display screen. Systematic errors of pupil size estimation were found with all three systems. Implications for task-elicited pupillometry, especially for gaze-contingent studies such as object tracking or reading, are discussed.

Automatic classification of eye activity for cognitive load measurement with emotion interference

Measuring cognitive load changes can contribute to better treatment of patients, can help design effective strategies to reduce medical errors among clinicians and can facilitate user evaluation of health care information systems. This paper proposes an eye-based automatic cognitive load measurement (CLM) system toward realizing these prospects. Three types of eye activity are investigated: pupillary response, blink and eye movement (fixation and saccade). Eye activity features are investigated in the presence of emotion interference, which is a source of undesirable variability, to determine the susceptibility of CLM systems to other factors. Results from an experiment combining arithmetic-based tasks and affective image stimuli demonstrate that arousal effects are dominated by cognitive load during task execution. To minimize the arousal effect on CLM, the choice of segments for eye-based features is examined. We then propose a feature set and classify three levels of cognitive load. The performance of cognitive load level prediction was found to be close to that of a reaction time measure, showing the feasibility of eye activity features for near-real time CLM.

A review of eye-tracking applications as tools for training

Substantial literature exists regarding how eye-tracking systems can be used to measure cognitive load and how these measurements can be useful for adapting training in real time. Much of the published literature discusses the applications and limitations of the research and typically provides recommendations for improvement. This review assesses these articles collectively to provide a clearer solution for implementing eye-tracking systems into a training environment. Although limitations exist for using eye tracking as an interface tool, gaze and pupillary response have been successfully used to reflect changes in cognitive load and are starting to be incorporated into adaptive training systems, although issues are still present with differentiating pupil responses from simultaneous psychological effects. Additionally, current eye-tracking systems and data analysis software have proven accurate enough for general use, but issues including system cost and software integration prevent this technology from becoming commercialized for use in common instructional settings.

Solving complex problems: A convergent approach to cognitive load measurement

AbstractThe study challenged the current practices in cognitive load measurement involving complex problem solving by manipulating the presence of pictures in multiple rule‐based problem‐solving situations and examining the cognitive load resulting from both off‐line and online measures associated with complex problem solving. Forty‐eight participants were recruited from a subject pool in the Educational Psychology department in a large research university in western USA. Results showed that the presence of pictures had no effect on learners' complex problem solving as measured by the response time and accuracy. However, the online measure (eg, pupillometric measures) revealed a change in cognitive load associated with the presence of pictures in complex problem solving. The authors concluded that different measures of cognitive load may actually be measuring separate aspects of cognitive load. Discussions were made on how research on multimedia learning and cognitive load could be advanced by carefully considering multiple aspects of cognitive load and by including the use of convergent measurement techniques to capture the variations of cognitive load involved in learning.

Spatially distributed instructions improve learning outcomes and efficiency.

Learning requires applying limited working memory and attentional resources to intrinsic, germane, and extraneous aspects of the learning task. To reduce the especially undesirable extraneous load aspects of learning environments, cognitive load theorists suggest that spatially integrated learning materials should be used instead of spatially separated materials, thereby reducing the split-attention effect (Sweller & Chandler, 1994). Recent work, however, has suggested a new distinction between two common formats of spatially separated displays: spatially distributed versus spatially stacked (Jang & Schunn, 2010). Moreover, a distinction between instructions and learning task materials has rarely been made. Across two studies with 106 college students (56 in Study 1 and 50 in Study 2), we compared spatially distributed (multiple sources of information are placed side by side) versus spatially stacked (only one at the top is visible) instructions, without changing the learning task materials, on both task performance and learning. With materials more typical of practice, Study 1 showed that the distributed-display instructions led learners to more efficient learning; learners finished the task faster and scored higher in the overall learning test. With materials more tightly controlled for spatial format per se, Study 2 replicated the effect and found that the benefit of the distributed instructions appeared to be associated with changes in cognitive load. Implications for educational practice are discussed.

Evaluation of multimodal feedback effects on improving rowing competencies

This study focused on the selection and preliminary evaluation of different types of modal and information feedback in virtual environment to facilitate acquisition and transfer of a complex motor-cognitive skill of rowing. Specifically, we addressed the effectiveness of immediate information feedback provided visually as compared to sensory haptic feedback on the improvement in hands kinematics and changes in cognitive load during the course of learning the basic rowing technique. Several pilot experiments described in this report lead to the evaluation and optimization of the training protocol, to enhance facilitatory effects of adding visual and haptic feedback during training.

Modulation of steady state functional connectivity in the default mode and working memory networks by cognitive load

Interregional correlations between blood oxygen level dependent (BOLD) magnetic resonance imaging (fMRI) signals in the resting state have been interpreted as measures of connectivity across the brain. Here we investigate whether such connectivity in the working memory and default mode networks is modulated by changes in cognitive load. Functional connectivity was measured in a steady-state verbal identity N-back task for three different conditions (N = 1, 2, and 3) as well as in the resting state. We found that as cognitive load increases, the functional connectivity within both the working memory the default mode network increases. To test whether functional connectivity between the working memory and the default mode networks changed, we constructed maps of functional connectivity to the working memory network as a whole and found that increasingly negative correlations emerged in a dorsal region of the posterior cingulate cortex. These results provide further evidence that low frequency fluctuations in BOLD signals reflect variations in neural activity and suggests interaction between the default mode network and other cognitive networks.

Distribution of cognitive load in Web search

AbstractThe search task and the system both affect the demand on cognitive resources during information search. In some situations the demands may become too high for a person. This article has a three‐fold goal. First, it presents and critiques methods to measure cognitive load. Second, it explores the distribution of load across search task stages. Finally, it seeks to improve our understanding of factors affecting cognitive load levels in information search. To this end, a controlled Web search experiment with 48 participants was conducted. Interaction logs were used to segment search tasks semiautomatically into task stages. Cognitive load was assessed using a new variant of the dual‐task method. Average cognitive load was found to vary by search task stages. It was significantly higher during query formulation and user description of a relevant document as compared to examining search results and viewing individual documents. Semantic information shown next to the search results lists in one of the studied interfaces was found to decrease mental demands during query formulation and examination of the search results list. These findings demonstrate that changes in dynamic cognitive load can be detected within search tasks. Dynamic assessment of cognitive load is of core interest to information science because it enriches our understanding of cognitive demands imposed on people engaged in the search process by a task and the interactive information retrieval system employed.