Changes In Task Difficulty Research Articles

The relationship between approval-based contingent self-esteem and conformity is influenced by sex and task difficulty

Individuals are often faced with the pressure to alter their behaviors or attitudes in order to conform. Researchers have used self-esteem level to explain such conformity but have failed to account for other aspects of self-esteem. The present study examined how approval-based contingent self-esteem (i.e., basing feelings of self-worth on the approval of others) moderates the association between self-esteem level and the tendency to conform. Participants (N=126) reported their self-esteem level and approval-based contingent self-esteem before completing an online conformity task that varied in difficulty. The results of the study showed that approval-based contingent self-esteem and sex moderated the association between self-esteem level and conformity in ways that were not always predicted. For example, men with approval-based contingent high self-esteem conformed more often on moderately difficult items than men who possessed non-contingent high self-esteem. These results suggest the possibility that different motivations may underlie the tendency to conform as task difficulty changes.

Failure of Intuition When Choosing Whether to Invest in a Single Goal or Split Resources Between Two Goals

In a series of related experiments, we asked people to choose whether to split their attention between two equally likely potential tasks or to prioritize one task at the expense of the other. In such a choice, when the tasks are easy, the best strategy is to prepare for both of them. As difficulty increases beyond the point at which people can perform both tasks accurately, they should switch strategy and focus on one task at the expense of the other. Across three very different tasks (target detection, throwing, and memory), none of the participants switched their strategy at the correct point. Moreover, the majority consistently failed to modify their strategy in response to changes in task difficulty. This failure may have been related to uncertainty about their own ability, because in a version of the experiment in which there was no uncertainty, participants uniformly switched at an optimal point.

Levels of attention and task difficulty in the modulation of interval duration mismatch negativity.

Time perception has been described as a fundamental skill needed to engage in a number of higher level cognitive processes essential to successfully navigate everyday life (e.g., planning, sequencing, etc.) Temporal processing is often thought of as a basic neural process that impacts a variety of other cognitive processes. Others, however, have argued that timing in the brain can be affected by a number of variables such as attention and motivation. In an effort to better understand timing in the brain at a basic level with minimal attentional demands, researchers have often employed use of the mismatch negativity (MMN). MMN, specifically duration MMN (dMMN) and interval MMN (iMMN) have been popular methods for studying temporal processing in populations for which attention or motivation may be an issue (e.g., clinical populations, early developmental studies). There are, however, select studies which suggest that attention may in fact modify both temporal processing in general and the MMN event-related potential. It is unclear the degree to which attention affects MMN or whether the effects differ depending on the complexity or difficulty of the MMN paradigm. The iMMN indexes temporal processing and is elicited by introducing a deviant interval duration amid a series of standards. A greater degree of difference in the deviant from the standard elicits a heightened iMMN. Unlike past studies, in which attention was intentionally directed toward a closed-captioned move, the current study had participants partake in tasks involving varying degrees of attention (passive, low, and high) with varying degrees of deviants (small, medium, and large) to better understand the role of attention on the iMMN and to assess whether level of attention paired with changes in task difficulty differentially influence the iMMN electrophysiological responses. Data from 19 subjects were recorded in an iMMN paradigm. The amplitude of the iMMN waveform showed an increase with attention, particularly for intervals that were the most distinct from a standard interval (p < 0.02). Results suggest that the role of attention on the iMMN is complex. Both the degree of attention paid as well as the level of difficulty of the MMN task likely influence the neuronal response within a timing network. These results suggest that electrophysiological perception of time is modified by attention and that the design of the iMMN study is critical to minimize the possible confounding effects of attention. In addition, the implications of these results for future studies assessing interval duration-based MMN in clinical populations is also addressed.

The Effects of Workload Transitions in a Multitasking Environment

Interest in workload transitions is centered on the hypothesis that transitions from one level of task difficulty to another may negatively impact performance on those tasks, and result in potentially critical impacts on professionals such as air traffic controllers and emergency medical staff. The current study sought to determine the effect of workload transitions on participants’ neurophysiological signals and performance. Participants completed trials in the Air Force Multi-Attribute Task Battery (AF-MATB; Miller, 2010), while Electroencephalography (EEG), Electrocardiography (ECG) and Electrooculogram (EOG) signals were recorded. All participants completed AF-MATB trials that delivered consistently low or high task difficulty, and trials that transitioned from an easy level to a difficult level and vice versa. Additionally, participants completed the NASA Task Load Index to assess subjective workload, and the shortened Dundee Stress State Questionnaire to measure subjective task-related stress during their testing sessions. Analyses of the performance data provide limited support for a negative impact of transitions from hard-to-easy, and the analysis of both the NASA Task Load Index and of the shortened Dundee State Questionnaire did not reveal any significant differences related to workload transitions. Analysis of the EEG data revealed that temporal gamma oscillations rapidly changed following a transition and settled after easy-to-hard changes in task difficulty, but settled more slowly after the task transitioned from hard-to-easy. Frontal theta oscillations, in contrast, exhibited consistently rapid settling which may indicate rapid changes in working memory utilization and conflict resolution (Gevins, et al., 1997). These EEG results suggest potential for further research.

Levels of agreement between student and staff assessments of clinical skills in performing cavity preparation in artificial teeth

To determine the level of agreement between staff and students' assessment of clinical skills in performing tasks related to cavity preparation on a traditional dental manikin. Two studies were conducted with two successive student cohorts: Study 1-138year 1 BDS students in a 2009/10 cohort and Study 2-135 students in a 2010/11 cohort. Staff members and students rated the students' performance in preparing a cavity on a traditional dental manikin using artificial teeth: hand-held (Study 1) and located in a lower jaw (Study 2). A 5-item criterion-related scoring rubric was developed. The rubric assessed students' abilities to hold the instrument correctly, determine the angle of entry to the tooth, remove the caries, conserve healthy tissues and avoid pulp exposure. Agreement between the students' self-assessment and the staff's assessment was high for three of the five criteria (i.e. removal of artificial caries on the cavity wall, removal of artificial caries from the cavity floor and avoidance of pulp exposure). Levels of agreement for the remaining two criteria were moderate. A change in task difficulty affected the levels of agreement between staff and students, such that the more difficult the task, the greater the discrepancy in ratings. Students tend to overrate the quality of their performance when compared with staff ratings. Task difficulty has an impact on levels of agreement.

Gender and age effects interact in preschoolers' help-seeking: evidence for differential responses to changes in task difficulty

This study explored preschool age and gender differences in help-seeking within the theoretical framework of scaffolded problem-solving and self-regulation (Bruner, 1986; Rogoff, 1990; Vygotsky, 1978; 1986). Within-subject analyses tracked changes in help-seeking among 62 preschoolers (34 boys, 28 girls, mean age 4.22 years) solving a challenging puzzle with an adult. The goal was to document whether age and gender interact with fluctuating difficulty to affect children's spontaneous help-seeking. ANOVAs indicated that girls used more help-seeking during difficult segments of the task, despite performance equal to the boys. This pattern was strongest among older girls, who outperformed all other children and used the most help-seeking. Partial correlations, controlling for solving time, indicated that age predicted children's help-seeking during the most difficult segments of the task, but only among girls. Gender differences in social-linguistic maturation and cognitive development are discussed within the framework of Vygotskian theory and related educational practice.

Understanding searchers' perception of task difficulty: Relationships with task type

We report findings that help us better understand the difficulty of tasks which involve information seeking, retrieving, gathering, and use. We examined the data gathered from two interactive information retrieval user studies on how users' perception of task difficulty changes before and after searching for information to solve tasks, and how the difficulty of tasks relates with users' background, previous experience with the tasks, and knowledge of the task topics, etc. The two studies employed carefully designed tasks with different types along several dimensions: task structure (subtasks being dependent upon or parallel with each other), task goal in quality (being specific or amorphous), and naming (being named or unnamed). It was found that while in some types of tasks, users' perceptions of task difficulty did not change before and after working on the tasks, in others, this did, either increasing or decreasing. Specifically, in the dependent-structured task, this did not change. In the parallel-structured or specific/named task, it decreased. In the amorphous/unnamed task, it increased. We also found that users' background factors do not normally correlate with their perceived task difficulty, or perceived difficulty change. In addition to helping understand the dynamic and complex nature of task difficulty, our findings have implications for system design that can provide assistance to users with their search and task solving strategies.

Transcranial Doppler Assessment of Workload Transition in a Complex Task

Previous research has demonstrated that the level of performance achieved for a given workload level is affected not only on task demands and individual differences, but also by sequential effects of prior workload. The majority of this research has been done with vigilance-type tasks, wherein performance is an intermittent response to critical signals. Workload is then varied either by adjusting the signal rate or adding a secondary task. This study sought to demonstrate that workload can be assessed with Transcranial Doppler (TCD) in addition to performance and other physiological measures, and that workload transition results generalize to more complex tasks. TCD and electrocardiographic (ECG) data were collected while participants performed the Multi-Attribute Task Battery (MATB, Comstock &amp; Arnegard, 1992). Two levels of workload were individually defined based on performance via a pretest calibration procedure; one level was relatively easy with a mean composite TLX score of 23 and the other relatively difficult with a mean composite TLX score of 63. These two levels were run in isolation and in transition runs that switched from one to the other halfway through. TCD and ECG revealed that both blood flow velocity and heart rate increased with increasing task difficulty, while the transition in task difficulty produced nonsignifcantly lower performance than runs of consistent difficulty. The physiological data provides evidence that additional physical resources are demanded and consumed in response to the change in task difficulty, while performance data collected to date has not revealed transition effects in the complex task.

Emotional consequences when chimpanzees (Pan troglodytes) face challenges: individual differences in self-directed behaviours during cognitive tasks

AbstractSelf-directed behaviours (SDBs) are said to be indicative of negative emotions. The present study focused on chimpanzees’ SDBs during cognitive experiments in order to investigate how each chimpanzee reacted to his or her errors and to changes in task difficulty. We recorded and analysed the behaviour of six chimpanzees during cognitive experiments at the Primate Research Institute, Kyoto University, in Japan. We compared the rate of SDBs after correct trials versus incorrect trials, and in easy tasks versus difficult tasks. Our results suggest that the chimpanzees’ reactions to making an error and the degree of difficulty of the task varied depending on the individual. Three out of the six chimpanzees exhibited higher rates of SDBs after incorrect trials than after correct trials, and in difficult tasks than in easy tasks whilst the other three did not. This finding suggests that chimpanzees may differ in the degree to which they exhibit internal conflict and we should carefully assess subjective evaluations of task situations; taking these differences into consideration when conducting experimental research in chimpanzees.

Motor Adaptation Scaled by the Difficulty of a Secondary Cognitive Task

BackgroundMotor learning requires evaluating performance in previous movements and modifying future movements. The executive system, generally involved in planning and decision-making, could monitor and modify behavior in response to changes in task difficulty or performance. Here we aim to identify the quantitative cognitive contribution to responsive and adaptive control to identify possible overlap between cognitive and motor processes.Methodology/Principal FindingsWe developed a dual-task experiment that varied the trial-by-trial difficulty of a secondary cognitive task while participants performed a motor adaptation task. Subjects performed a difficulty-graded semantic categorization task while making reaching movements that were occasionally subjected to force perturbations. We find that motor adaptation was specifically impaired on the most difficult to categorize trials.Conclusions/SignificanceWe suggest that the degree of decision-level difficulty of a particular categorization differentially burdens the executive system and subsequently results in a proportional degradation of adaptation. Our results suggest a specific quantitative contribution of executive control in motor adaptation.

Neurodevelopmental changes in verbal working memory load-dependency: An fMRI investigation

Development of working memory (WM) aptitude parallels structural changes in the frontal–parietal association cortices important for performance within this cognitive domain. The cerebellum has been proposed to function in support of the postulated phonological loop component of verbal WM, and along with frontal and parietal cortices, has been shown to exhibit linear WM load-dependent activation in adults. It is not known if these kinds of WM load-dependent relationships exist for cerebro-cerebellar networks in developmental populations, and whether there are age-related changes in the nature of load-dependency between childhood, adolescence, and adulthood. The present study used fMRI and a verbal Sternberg WM task with three load levels to investigate developmental changes in WM load-dependent cerebro-cerebellar activation in a sample of 30 children, adolescents, and young adults between the ages of 7 and 28. The neural substrates of linear load-dependency were found to change with age. Among adolescents and adults, frontal, parietal and cerebellar regions showed linear load-dependency, or increasing activation under conditions of increasing WM load. In contrast, children recruited only left ventral prefrontal cortex in response to increasing WM load. These results demonstrate that, while children, adolescents, and young adults activate similar cerebro-cerebellar verbal working memory networks, the extent to which they rely on parietal and cerebellar regions in response to increasing task difficulty changes significantly between childhood and adolescence.

Construct validity of computer-assisted assessment: quantification of movement processes during a vascular anastomosis on a live porcine model

Background Movement processes for 2 different suturing techniques within a single surgical task were quantified. Methods Junior (postgraduate years 1–2) and senior residents (postgraduate year 3 and higher) were tested on their ability to perform a vascular anastomosis on a live porcine model 1 week after a guided practice session. Two phases of 2 suturing techniques (parachute and running) were identified, and performance was evaluated during each phase using computer hand motion analysis (CHMA) and expert-based measures. Results Senior residents were more efficient on all segments based on CHMA and expert-based ratings ( P < .05). CHMA showed a significant improvement in junior resident performance during each phase of the procedure (warm-up effect). The change in task difficulty during transition from parachute to running sutures was identifiable using CHMA. Conclusions Different suturing techniques are executed using the same general motor program although specific program parameters are adjusted to suit each technique. The findings support a novel form of construct validity the for surgical assessment device, the concept of transfer of skills, and the use of computer evaluations for the assessment of technical skills embedded within complex surgical tasks.

Effects of task difficulty and time‐on‐task on mental workload

Abstract:Twelve subjects performed a tracking task and a memory search task simultaneously on a computer screen. The dual task continued for approximately 10 min and was repeated three times, interrupted by a short break for subjective ratings: the NASA Task Load Index (NASA‐TLX) and the Check List of Mental Condition. Event related potentials (ERP) evoked by the presentation of memory task stimuli were also recorded. All the subjects participated in three experimental sessions, which varied in difficulty of tracking task. Results demonstrated that the NASA‐TLX and ERP were sensitive only to the change in task difficulty and were not affected by time‐on‐task or interaction between task difficulty and time‐on‐task.

Effects of cognitive challenge on self-directed behaviors by chimpanzees (Pan troglodytes).

In primates, including humans, scratching and other self-directed behaviors (SDBs) have recently been reported to be differentially displayed as a function of social interactions, anxiety-related drugs, and response outcomes during learning tasks. Yet few studies have focused on the factors influencing SDBs in our closest living relatives, the chimpanzees (Pan troglodytes). Furthermore, no previous experimental study has examined handedness of SDBs as a function of changes in task difficulty. Using matching-to-sample tasks of varying difficulty, the present study examines the effect of manipulations of task difficulty on rates, handedness, and type of SDBs in an experimental study of eight chimpanzees. SDBs were categorized as rubs, gentle scratches, and rough scratches. SDBs increased during difficult discriminations, but only for subjects who started the experiment on an easy discrimination; subjects who started on a difficult discrimination exhibited no differential rates of SDBs as a function of task difficulty. There was a tendency to exhibit relatively more SDBs with the right hand in the more difficult task. Rates of SDBs decreased after auditory feedback signals, suggesting a link between SDBs and uncertainty. Rubs were directed more to the face (trigeminal), and gentle and rough scratches more to the body (spinothalamic), suggesting that face-directed SDBs may index a different motivational basis than scratches. Taken together, these results extend previous research on SDBs to the domain of cognitive stress in nonsocial contexts, demonstrating that SDBs are sensitive to manipulations of task difficulty in chimpanzees.

Age-Related Changes in Psychomotor Performance

The purpose of this investigation was to assess the influence of age relative to the response to changes in task difficulty within the performance of a discrete pursuit tracking task by adults from 20-89 years old. The results obtained suggest that although there was a significant age-related decrement in psychomotor performance, it was most prevalent in the 70-79 and 80-89 years age group. However, the data were quite stable across the younger age groups: 20-60 years. Hence, although providing support for the contention of age-related decrements in psychomotor performance with increasing age, this investigation indicates that the decrements may not be as dramatic or immediate as some studies may have previously implied.

An Examination of the Impact of Changes in Task Difficulty on Decision-Making Groups Relying on an Automated Communication System

An Examination of the Impact of Changes in Task Difficulty on Decision-Making Groups Relying on an Automated Communication System

Aging and the Response to Changes in Task Difficulty

RÉSUMÉUn exercice de repérage de signaux discontinus a été employé pour évaluer le processus de planification du mouvement (relié aux paramètres de direction et d'amplitude) comme source du ralentissement de l'initiation et de la production du mouvement chez les personnes âgées. Les personnes âgées ont démontré des temps de réaction et de mouvement plus lents, cette lenteur variant en fonction de la quantité d'informations traitées pour accomplir le mouvement. Cependant, les personnes âgées ont semblé aussi capables que des individus plus jeunes de corriger des erreurs imprévues de mouvement. Les données suggèrent que, bien que le processus de sélection du mouvement puisse constituer un facteur qui contribue au ralentissement chez les personnes âgées, l'identification de paramètres spécifiques du mouvement peut s'avérer plus importante dans l'accomplissement de certains mouvements que les quelques déficits généralisés associés au vieillissement.

A Validation of SWAT as a Measure of Workload Induced by Changes in Operator Capacity

The primary focus of much of the workload research over the years has been the sensitivity of the mental workload measures to changes in task demands. However, as Wickens (1984) hypothesizes, the construct of workload is, in actuality, an interaction between the supply of operator mental resources available to devote to a task and to the demands of that task (i.e., “residual capacity”). Therefore, workload fluctuations can occur from either changes in operator capacity or changes in task demand. A study was performed to investigate the interactive effects of workload induced by changes in task difficulty, fatigue induced by time-on-task and fatigue induced by sleep deprivation on pilot performance. The focus of the current paper is on a finding that Subjective Workload Assessment Technique (SWAT) varied reliably for both the main effects of time-on-task and sleep deprivation, as well as for task difficulty. This finding indicates that SWAT, and probably subjective measures in general, are sensitive to workload induced by changes in operator capacity induced by fatigue. Implications of this finding for workload measurement in general are discussed.

Techniques of Subjective Assessment: A Comparison of the SWAT and Modified Cooper-Harper Scales

This study examined two subjective mental workload assessment scales, the Subjective Workload Assessment Technique (SWAT) and the Modified Cooper-Harper (MCH) Scale. The purpose of this study was to make a direct comparison of the two scales in order to determine if both scales were equally sensitive to changes in task difficulty hence, workload. Forty introductory psychology non-aviator students were trained on an aviation like psychomotor dual-task experiment. Task difficulty was manipulated by presenting the subjects with three (low, moderate, high) levels of wind gust disturbance (turbulence) and requiring them to maintain an assigned altitude and airspeed, while responding to a visual choice reaction time secondary task. The data was analyzed using multivariate statistics. The results of the analysis found that both the SWAT and MCH were sensitive to changes in task difficulty. However, the MCH appeared to be less sensitive than the SWAT.

Information processing deficits in Parkinson's disease during movement

The capacity to process information during movement selection and execution was studied in Parkinsonian patients and controls in a task involving movement of a hand-held stylus between two targets whose size and separation could be systematicaly varied. Movement time and accuracy were evaluated when the size and required accuracy of movements were changed to modify movement difficulty. Movement time and inaccuracy of patients with Parkinson's disease were exaggerated by increasing target separation so as to increase movement extent (target size held constant) or by decreasing target size (target separation held constant). The fact that these changes in task difficulty caused greater deterioration of performance for patients than for controls is consistent with previous studies indicating that Parkinsonian patients have deficits in executing high-velocity movements. These data also show that performance deficits by Parkinsonian patients can be brought out by increasing movement difficulty through requiring increased movement accuracy. These findings are interpreted in relation to the relative contribution of deficits in movement execution vs motor programming in the motor disorders of Parkinson's disease.