Index Of Mental Workload Research Articles

Robotic versus Laparoscopic Inguinal Hernia Repair; A Prospective Study

Abstract Background Robotic inguinal hernia repair has certain advantages over laparoscopic repair including less pain and earlier return to normal activity. Robotic surgery adds high definition visualization and articulating instruments. This enhanced dexterity can make laparoscopic hernia repair more refined while obtaining a critical view of the myopectineal orifice that should lead to fewer recurrences and complications. Aim of the Work To compare early postoperative outcomes and surgical ergonomics between robotic and laparoscopic inguinal hernia repair. Patients and Methods This study is a prospective study, conducted in Ain Shams specialized Hospital during one year (March 2022 - March 2023). Patients above 16 year old who had inguinal hernia. Results The RULA was used to assess the ergonomic status of surgeons involved in this trial. RULA is a survey method originally developed for use in workplaces where risk exists for work-related upper limb injuries, often related to poor ergonomics combined with repetitive motion. It provides an assessment of the postures of the neck, trunk, and upper limb along with muscle function and the external loads experienced. The NASA-TLX validated instrument was used to determine the mental workload of surgeons, and has precedent as a tool to evaluate the mental workload of surgeons in minimally invasive surgery. The NASA-TLX provides an overall index of mental workload as well as the relative contribution of 6 subscales: mental, physical, and temporal task demands, effort, frustration, and perceived performance. Mental demand determines the level of intellectual and perceptual work required for completion of a task and physical demand determines the level of physical work required for completion of a task. Temporal demand is the measure for time pressure during the completion of the task. The effort component assesses mental and physical work required to perform at a certain proficiency level. Conclusion The benefits provided by the robotic platform include better visualization, improved ergonomics and wristed movements allowing for easier dissection.

Analisis Beban Kerja Mental Dosen Fakultas XYZ Menggunakan Metode Nasa TLX

Employee performance is influenced by several things, one of which is work stress. Unresolved stress results in a person's inability to interact positively with their environment. XYZ Faculty is one of the faculties in a private university in the Yogyakarta area. Based on personnel data, the average 2023 BKD for XYZ Faculty lecturers is 18.65. This creates an excessive burden on lecturers. This research aims to measure the mental workload index of XYZ faculty lecturers and develop recommendations for improvement to balance the workload. The method used in this research is the Nasa TLX method. The results of the research show that the workload experienced by lecturers at Faculty so that administrative activities do not interfere with lecturers' tri dharma activities.

Reliability of Mental Workload Index Assessed by EEG with Different Electrode Configurations and Signal Pre-Processing Pipelines.

Mental workload (MWL) is a relevant construct involved in all cognitively demanding activities, and its assessment is an important goal in many research fields. This paper aims at evaluating the reproducibility and sensitivity of MWL assessment from EEG signals considering the effects of different electrode configurations and pre-processing pipelines (PPPs). Thirteen young healthy adults were enrolled and were asked to perform 45 min of Simon's task to elicit a cognitive demand. EEG data were collected using a 32-channel system with different electrode configurations (fronto-parietal; Fz and Pz; Cz) and analyzed using different PPPs, from the simplest bandpass filtering to the combination of filtering, Artifact Subspace Reconstruction (ASR) and Independent Component Analysis (ICA). The reproducibility of MWL indexes estimation and the sensitivity of their changes were assessed using Intraclass Correlation Coefficient and statistical analysis. MWL assessed with different PPPs showed reliability ranging from good to very good in most of the electrode configurations (average consistency > 0.87 and average absolute agreement > 0.92). Larger fronto-parietal electrode configurations, albeit being more affected by the choice of PPPs, provide better sensitivity in the detection of MWL changes if compared to a single-electrode configuration (18 vs. 10 statistically significant differences detected, respectively). The most complex PPPs have been proven to ensure good reliability (>0.90) and sensitivity in all experimental conditions. In conclusion, we propose to use at least a two-electrode configuration (Fz and Pz) and complex PPPs including at least the ICA algorithm (even better including ASR) to mitigate artifacts and obtain reliable and sensitive MWL assessment during cognitive tasks.

Ambient Light Conveying Reliability Improves Drivers’ Takeover Performance without Increasing Mental Workload

Drivers of L3 automated vehicles (AVs) are not required to continuously monitor the AV system. However, they must be prepared to take over when requested. Therefore, it is necessary to design an in-vehicle environment that allows drivers to adapt their levels of preparedness to the likelihood of control transition. This study evaluates ambient in-vehicle lighting that continuously communicates the current level of AV reliability, specifically on how it could influence drivers’ take-over performance and mental workload (MW). We conducted an experiment in a driving simulator with 42 participants who experienced 10 take-over requests (TORs). The experimental group experienced a four-stage ambient light display that communicated the current level of AV reliability, which was not provided to the control group. The experimental group demonstrated better take-over performance, based on lower vehicle jerks. Notably, perceived MW did not differ between the groups, and the EEG indices of MW (frontal theta power, parietal alpha power, Task–Load Index) did not differ between the groups. These findings suggest that communicating the current level of reliability using ambient light might help drivers be better prepared for TORs and perform better without increasing their MW.

This Is Your Brain on Autopilot: Neural Indices of Driver Workload and Engagement During Partial Vehicle Automation.

This research explores the effect of partial vehicle automation on neural indices of mental workload and visual engagement during on-road driving. There is concern that the introduction of automated technology in vehicles may lead to low driver stimulation and subsequent disengagement from the driving environment. Simulator-based studies have examined the effect of automation on a driver's cognitive state, but it is unknown how the conclusions translate to on-road driving. Electroencephalographic (EEG) measures of frontal theta and parietal alpha can provide insight into a driver's mental workload and visual engagement while driving under various conditions. EEG was recorded from 71 participants while driving on the roadway. We examined two age cohorts, on two different highway configurations, in four different vehicles, with partial vehicle automation both engaged and disengaged. Analysis of frontal theta and parietal alpha power revealed that there was no change in mental workload or visual engagement when driving manually compared with driving under partial vehicle automation. Drivers new to the technology remained engaged with the driving environment when operating under partial vehicle automation. These findings suggest that the concern surrounding driver disengagement under vehicle automation may need to be tempered, at least for drivers new to the experience. These findings expand our understanding of the effects of partial vehicle automation on drivers' cognitive states.

Sensitivity of the Spatial Distribution of Fixations to Variations in the Type of Task Demand and Its Relation to Visual Entropy.

Ocular activity is known to be sensitive to variations in mental workload, and recent studies have successfully related the distribution of eye fixations to the mental load. This study aimed to verify the effectiveness of the spatial distribution of fixations as a measure of mental workload and its sensitivity to different types of demands imposed by the task: mental, temporal, and physical. To test the research hypothesis, two experimental studies were run: Experiment 1 evaluated the sensitivity of an index of spatial distribution (Nearest Neighbor Index; NNI) to changes in workload. A sample of 30 participants participated in a within-subject design with different types of task demands (mental, temporal, physical) applied to Tetris game; Experiment 2 investigated the accuracy of the index through the analysis of 1-min epochs during the execution of a visual-spatial task (the “spot the differences” puzzle game). Additionally, NNI was compared to a better-known ocular mental workload index, the entropy rate. The data analysis showed a relation between the NNI and the different workload levels imposed by the tasks. In particular: Experiment 1 demonstrated that increased difficulty, due to higher temporal demand, led to a more dispersed pattern with respect to the baseline, whereas the mental demand led to a more grouped pattern of fixations with respect to the baseline; Experiment 2 indicated that the entropy rate and the NNI show a similar pattern over time, indicating high mental workload after the first minute of activity. That suggests that NNI highlights the greater presence of fixation groups and, accordingly, the entropy indicates a more regular and orderly scanpath. Both indices are sensitive to changes in workload and they seem to anticipate the drop in performance. However, the entropy rate is limited by the use of the areas of interest, making it impossible to apply it in dynamic contexts. Conversely, NNI works with the entire scanpath and it shows sensitivity to different types of task demands. These results confirm the NNI as a measure applicable to different contexts and its potential use as a trigger in adaptive systems implemented in high-risk settings, such as control rooms and transportation systems.

The effect of sleep-need and time-on-task on driver fatigue

Both sleep- and task-related factors are thought to contribute to driver fatigue, with each factor individually associated with deteriorated driving performance. However, the relative and combined effects of these factors in the context of monotonous driving have not been well studied. This study (N = 60) investigated lateral and longitudinal vehicle control, subjective fatigue and physiological response (EEG) during three 10-minute periods of time-on-task spread across a monotonous, 2-hour simulator drive. Level of physiological sleep-need was manipulated between participants by varying the instructed time spent in bed on the night before testing (≤5h or ≥ 8 h). In addition, half of the participants in each sleep group read the applicable speed limit from periodic roadside signs whereas the others performed an arithmetic calculation, displayed on the signs, to determine the speed limit. This task manipulation has been demonstrated to reduce performance decrements over time. Results demonstrated effects of time-on-task and sleep need on self-report ratings, an effect of time-on-task on EEG indices, and an interaction of sleep-need and time-on-task on an EEG index of mental workload and on the lateral control measure of driving performance. There were no significant effects on the measure of speed variability. These results confirm that both sleep-need and time-on-task negatively affect driver state, and that time-on-task decrements in driver performance can occur in the absence of heightened sleep-need. Results also suggest that drivers with heightened sleep-need could protect their performance for a short time, perhaps by exerting effort to compensate for reduced capacity. The secondary task did not counteract declining performance.

Evaluation of the effect of a newly developed steering unit with enhanced self-alignment and deadband on mental workload during driving of agricultural tractors

The aim of present study was to investigate the effect of a newly developed steering unit with enhanced self-alignment and deadband on mental workload (MW) during heavy vehicle operation. Fourteen participants performed two tasks consisting of a lane keeping and a double lane shift with two tractors equipped with 1) a conventional and 2) an enhanced steering system. Physiological measurements, i.e., electromyography, electrodermal activity and heart rate were recorded during the tasks. Furthermore, performance measurements and subjective perception of MW were collected. Present study demonstrated that participants perceived the enhanced steering system requiring less mental demands to operate. Participants improved their performance during the lane keeping task and tended to improve in the double lane shift task with the enhanced system. Physiological measurements did not reveal differences between the steering systems. This study highlighted the dissociation of subjective indices of mental workload from physiological indices in driving of heavy vehicles.

EEG Theta Power Activity Reflects Workload among Army Combat Drivers: An Experimental Study.

We aimed to evaluate the effects of mental workload variations, as a function of the road environment, on the brain activity of army drivers performing combat and non-combat scenarios in a light multirole vehicle dynamic simulator. Forty-one non-commissioned officers completed three standardized driving exercises with different terrain complexities (low, medium, and high) while we recorded their electroencephalographic (EEG) activity. We focused on variations in the theta EEG power spectrum, a well-known index of mental workload. We also assessed performance and subjective ratings of task load. The theta EEG power spectrum in the frontal, temporal, and occipital areas were higher during the most complex scenarios. Performance (number of engine stops) and subjective data supported these findings. Our findings strengthen previous results found in civilians on the relationship between driver mental workload and the theta EEG power spectrum. This suggests that EEG activity can give relevant insight into mental workload variations in an objective, unbiased fashion, even during real training and/or operations. The continuous monitoring of the warfighter not only allows instantaneous detection of over/underload but also might provide online feedback to the system (either automated equipment or the crew) to take countermeasures and prevent fatal errors.

Investigating the effect of indoor thermal environment on occupants’ mental workload and task performance using electroencephalogram

Workers' performance in indoor offices can be greatly affected by the thermal condition of the environment. However, this effect can be difficult to quantify, especially when the thermal stress is a moderate increase or decrease in temperature and the work productivity cannot be directly measured. Subjects' high motivation to perform well under experimental conditions also causes difficulties in comparing their performance in different thermal environments. In order to overcome these limitations, this paper proposes a method to investigate the effect of the indoor thermal conditions on occupants' performance by studying occupants' mental workload measured by the electroencephalography (EEG) when they perform standardized cognitive tasks. An experiment integrating EEG mental workload measurement and cognitive tasks was implemented on 15 subjects. EEG data were collected while subjects were performing four cognitive tasks on computers. Based on previous studies, we propose a mental workload index calculated from the frontal theta and parietal alpha frequency band power. Within-subject comparisons were performed to investigate whether subjects' mental workload is statistically different under three different thermal environments, representing thermal sensations of slightly cool, neutral, and slightly warm. The results show that the effect of thermal environment varies across different individuals. By comparing the mental workload index among different thermal environments, we found that the slightly warm environment resulted in a relatively higher mental workload than the other two environments to achieve the same performance. The study provides promising insights into how the thermal environment influences occupants’ performance by affecting their mental workload from the neurophysiological perspective.

Event-related potentials as indices of mental workload while using an in-vehicle information system

New in-vehicle information systems are now being commercialized. Despite the expected benefits, some concerns exist that they may overload drivers’ capacity and decrease performance. According to the multiple resource theory (Wickens, Hum Factors 50:449–455, https://doi.org/10.1518/001872008X288394, 2008), overload may occur at different stages of processing, that is, perceptual–central and/or response-related stages. Therefore, different measures may be needed to detect such specific demands. We explored the sensitivity of different mental workload measurements during the performance of an auditory task alone (single task) and in combination with a tracking task that was presented without (dual task) or, with a visual display (triple task). The demands associated with the number of concurrent tasks (single, dual and triple tasks), tracking speed (low, high, adjustable) and their interaction were analyzed. To account for different processing requirements, mental workload was assessed using subjective, behavioral (performance on the auditory task) and psychophysiological measurements (event-related potentials). 17 young adults participated in the study. The results showed that most measurements discriminated between the performances of one or more tasks, as well as between low and high speeds. However, only the subjective ratings and tracking task performance further discriminated between the dual- and triple-task conditions. Finally, ERPs (N1 and P3) were the only measure detecting increases in cognitive demands associated with higher requirements on processing speed combined with the addition of the display. Our results suggest that ERPs may provide complementary information to other traditional mental workload measures. Its applications in the evaluation and design of future systems should be investigated.

Adaptive Automation Triggered by EEG-Based Mental Workload Index: A Passive Brain-Computer Interface Application in Realistic Air Traffic Control Environment.

Adaptive Automation (AA) is a promising approach to keep the task workload demand within appropriate levels in order to avoid both the under- and over-load conditions, hence enhancing the overall performance and safety of the human-machine system. The main issue on the use of AA is how to trigger the AA solutions without affecting the operative task. In this regard, passive Brain-Computer Interface (pBCI) systems are a good candidate to activate automation, since they are able to gather information about the covert behavior (e.g., mental workload) of a subject by analyzing its neurophysiological signals (i.e., brain activity), and without interfering with the ongoing operational activity. We proposed a pBCI system able to trigger AA solutions integrated in a realistic Air Traffic Management (ATM) research simulator developed and hosted at ENAC (École Nationale de l'Aviation Civile of Toulouse, France). Twelve Air Traffic Controller (ATCO) students have been involved in the experiment and they have been asked to perform ATM scenarios with and without the support of the AA solutions. Results demonstrated the effectiveness of the proposed pBCI system, since it enabled the AA mostly during the high-demanding conditions (i.e., overload situations) inducing a reduction of the mental workload under which the ATCOs were operating. On the contrary, as desired, the AA was not activated when workload level was under the threshold, to prevent too low demanding conditions that could bring the operator's workload level toward potentially dangerous conditions of underload.

A ship navigator’s mental workload using salivary NO3− concentration for simulator-based experiment

AbstractWe challenge an evaluation of a ship bridge teammate’s mental workload. If we are able to evaluate using a quantitative index for a veteran navigator, it means we get more essential skill for practical education, for example, the educators show students the detail suggestion of skill of ship maneuvering for simulator-based and real ship handling. We think that the both of performance and mental workload are important to evaluate the skill of ship maneuvering; however, the mental workload doesn’t use yet. Regarding the index of mental workload, the heart rate variability (HRV) is popular for a lot of research fields. We usual use HRV, nasal temperature, and try saliva. The saliva is possible to evaluate the mental workload on the spot for ship maneuvering. We hope simple measurement and clear result for the index, and it is practical method in a classroom. The spot measurement is one of research target.In this study, we aim salivary NO3− concentration for simulator-based experiment. We show the res...

Mobile Virtual Learning Object for the Assessment of Acute Pain as a Learning Tool to Assess Acute Pain in Nursing: An Analysis of the Mental Workload.

BackgroundThe inclusion of new technologies in education has motivated the development of studies on mental workload. These technologies are now being used in the teaching and learning process. The analysis enables identification of factors intervening in this workload as well as planning of overload prevention for educational activities using these technologies.ObjectiveTo analyze the mental workload of an educational intervention with the Mobile Virtual Learning Object for the Assessment of Acute Pain in adults and newborns, according to the NASA Task Load Index criteria.MethodsA methodological study with data collected from 5 nurses and 75 students, from November of 2013 to February of 2014.ResultsThe highest students’ and specialists’ means were in the dimensions of “Mental demand” (57.20 ± 22.27; 51 ± 29.45) and “Performance” (58.47 ± 24.19; 73 ± 28.85). The specialists’ mental workload index was higher (50.20 ± 7.28) when compared with students’ (47.87 ± 16.85) on a scale from 0 to 100 (P=.557).ConclusionsThe instrument allowed for the assessment of mental workload after an online educational intervention with a mobile learning virtual object. An excessive overload was not identified among participants. Assessing mental workload from the use of educational technologies at the end of a task is a key to their applicability, with the aim of providing a more effective, stimulating, and long-lasting experience of the learning process.

Measurement of Mental Workload Changes during Laparoscopy with a Visual-Spatial Task

A visual-spatial secondary task was used as a measure of mental workload during the performance of a simulated laparoscopic surgical task. Task demands were manipulated by an increase in the degree of camera angle. NASA-TLX scores were used to corroborate changes in task demands. Results indicated that performance on the visual-spatial secondary task decreased with the increase in task demands associated with the increase in camera angle. NASA-TLX scores were consistent with the performance measures revealing that participants felt the laparoscopic task was more demanding when camera angle increased. The use of similar workload assessment methods may allow for more accurate estimates of the mental demands imposed by laparoscopy. These results show that the spatial secondary task used in this study can provide an objective index of mental workload that can complement traditional measures.

Avionic technology testing by using a cognitive neurometric index: A study with professional helicopter pilots.

In this study, we investigated the possibility to evaluate the impact of different avionic technologies on the mental workload of helicopter's pilots by measuring their brain activity with the EEG during a series of simulated missions carried out at AgustaWestland facilities in Yeovil (UK). The tested avionic technologies were: i) Head-Up Display (HUD); ii) Head-Mounted Display (HMD); iii) Full Conformal symbology (FC); iv) Flight Guidance (FG) symbology; v) Synthetic Vision System (SVS); and vi) Radar Obstacles (RO) detection system. It has been already demonstrated that in cognitive tasks, when the cerebral workload increases the EEG power spectral density (PSD) in theta band over frontal areas increases, and the EEG PSD in alpha band decreases over parietal areas. A mental workload index (MWL) has been here defined as the ratio between the frontal theta and parietal alpha EEG PSD values. Such index has been used for testing and comparing the different avionic technologies. Results suggested that the HUD provided a significant (p<;.05) workload reduction across all the flight scenarios with respect to the other technologies. In addition, the simultaneous use of FC and FG technologies (FC+FG) produced a significant decrement of the workload (p<;.01) with respect to the use of only the FC. Moreover, the use of the SVS technology provided on Head Down Display (HDD) with the simultaneous use of FC+FG and the RO seemed to produce a lower cerebral workload when compared with the use of only the FC. Interestingly, the workload estimation by means of subjective measures, provided by pilots through a NASA-TLX questionnaire, did not provide any significant differences among the different flight scenarios. These results suggested that the proposed MWL cognitive neurometrics could be used as a reliable measure of the user's mental workload, being a valid indicator for the comparison and the test of different avionic technologies.

Mental workload estimations in unilateral deafened children.

Despite of technological innovations, noisy environments still constitute a challenging and stressful situation for words recognition by hearing impaired subjects. The evaluation of the mental workload imposed by the noisy environments for the recognition of the words in prelingually deaf children is then of paramount importance since it could affect the speed of the learning process during scholar period.The aim of the present study was to investigate different electroencephalographic (EEG) power spectral density (PSD) components (in theta 4-8 Hz - and alpha - 8-12 Hz - frequency bands) to estimate the mental workload index in different noise conditions during a word recognition task in prelingually deaf children, a population not yet investigated in relation to the workload index during auditory tasks. A pilot study involving a small group of prelingually deaf children was then subjected to EEG recordings during an auditory task composed by a listening and a successive recognition of words with different noise conditions. Results showed that in the pre-word listening phase frontal EEG PSD in theta band and the ratio of the frontal EEG PSD in theta band and the parietal EEG PSD in alpha band (workload index; IWL) reported highest values in the most demanding noise condition. In addition, in the phase preceding the word forced-choice task the highest parietal EEG PSD in alpha band and IWL values were reported at the presumably simplest condition (noise emitted in correspondence of the subject's deaf ear). These results could suggest the prominence of EEG PSD theta component activity in the pre-word listening phase. In addition, a more challenging noise situation in the pre-choice phase would be so "over-demanding" to fail to enhance both the alpha power and the IWL in comparison to the already demanding "simple" condition.

Psychophysiological Metrics for Workload are Demand-Sensitive but Multifactorial

Various psychophysiological indices of mental workload exhibit sensitivity to task demand factors, but the psychometrics of indices has been neglected. In particular, the extent to which different metrics converge on a common latent factor is unclear. In the present study, 150 participants performed in four task scenarios based on a simulation of unmanned vehicle operation. Scenarios required threat detection and/or change detection. Both single- and dual-task scenarios were used. Workload metrics were derived from the electroencephalogram (EEG), electrocardiogram (ECG), transcranial Doppler sonography (TCD), functional Near Infra-Red (fNIR) and eyetracking. Subjective workload was also assessed. Several metrics were appropriately sensitive to the differing levels of task load presented by the four scenarios. However, factor analysis identified multiple factors, each of which was associated with a single response system only, with no general factor. Caution should be used in assessing workload in the individual operator.

The psychometrics of mental workload: multiple measures are sensitive but divergent.

A study was run to test the sensitivity of multiple workload indices to the differing cognitive demands of four military monitoring task scenarios and to investigate relationships between indices. Various psychophysiological indices of mental workload exhibit sensitivity to task factors. However, the psychometric properties of multiple indices, including the extent to which they intercorrelate, have not been adequately investigated. One hundred fifty participants performed in four task scenarios based on a simulation of unmanned ground vehicle operation. Scenarios required threat detection and/or change detection. Both single- and dual-task scenarios were used. Workload metrics for each scenario were derived from the electroencephalogram (EEG), electrocardiogram, transcranial Doppler sonography, functional near infrared, and eye tracking. Subjective workload was also assessed. Several metrics showed sensitivity to the differing demands of the four scenarios. Eye fixation duration and the Task Load Index metric derived from EEG were diagnostic of single-versus dual-task performance. Several other metrics differentiated the two single tasks but were less effective in differentiating single- from dual-task performance. Psychometric analyses confirmed the reliability of individual metrics but failed to identify any general workload factor. An analysis of difference scores between low- and high-workload conditions suggested an effort factor defined by heart rate variability and frontal cortex oxygenation. General workload is not well defined psychometrically, although various individual metrics may satisfy conventional criteria for workload assessment. Practitioners should exercise caution in using multiple metrics that may not correspond well, especially at the level of the individual operator.

Board 386 - Research Abstract Measuring Changes in Skill Acquisition and Mental Workload on Two Laparoscopic Tasks (Submission #628)

Introduction/Background Laparoscopy places significant demands on visual attention and requires extensive practice to become proficient. Scerbo et al. have developed a method of assessing mental workload with a secondary task that requires spatial abilities.1,2 The task is based on multiple resource theory, which states that “pools” of attentional resources are distinguished by: information processing stages, verbal/spatial codes, and visual/auditory modalities.3 When two tasks performed simultaneously require the same pool of resources, they can interfere with one another and increase mental workload. Thus, when a secondary task requiring the same attentional resources needed for laparoscopy is performed with a laparoscopic task, it can provide an index of mental workload. Our goal was to use a spatial secondary task to measure mental workload during the initial acquisition of basic laparoscopic skills on a simulator. Performance on two laparoscopic tasks differing in difficulty was measured across training sessions. We hypothesized that mental workload would initially be high (and more so on the difficult task) but would decline over sessions as trainees became more proficient as indexed by secondary task performance. Methods Fourteen surgical assistant students with no prior laparoscopic experience participated in this IRB approved, repeated measures study. They practiced cutting (high difficulty) and peg transfer (low difficulty) tasks from the Fundamentals of Laparoscopic Surgery for approximately 45 min over 11 sessions and were assessed with the secondary task at the end of each session. The secondary task presented observers with four balls in a simulated tunnel, superimposed at 50% transparency over the laparoscopic display. The balls were presented for 300 msec approximately every 4 sec. On half the presentations, one ball changed its position and participants responded to that change by pressing a foot pedal. They performed the secondary task by itself and in conjunction with the laparoscopic tasks. Results All data were analyzed with a 2 Condition x 11 Session repeated measures ANOVA. There was a significant effect for laparoscopic tasks, F(1,11) = 15.72, p = .002, partial Æž2 =.59. Completion times were faster for the peg (M = 102.57 sec, SE = 5.30) than the cutting task (M = 121.90 sec, SE = 5.08). Times declined significantly over sessions, F(10,110) = 38.88, p < .001, partial Æž2 =.77, but leveled off by the sixth and second sessions for the peg and cutting tasks, respectively. There were significant effects for the secondary task scores, F(1,12) = 31.88, p = .000, partial Æž2 =.73. The proportion of correct responses for cutting (M = .36, SE = .07) was lower than for pegs (M = .46, SE = .07), and scores on both tasks were lower than the secondary task performed by itself. Scores increased over sessions,F(10,120) = 3.11, p = .001, partial Æž2 =.21; but only the difference between the first (M = .31, SE = .05) and eleventh session (M = .45, SE = .07) was significant. Conclusion The Results show that performance on the peg and cutting tasks reached a plateau midway through the training sessions. The findings for the spatial secondary task supported expectations. Workload was initially higher (lowers scores) and remained higher for the more difficult cutting task and although the scores increased over sessions for both tasks, the improvements were modest. These Results show that the mental workload experienced by novices practicing laparoscopic tasks may be quite high. They also support findings obtained by Stefanidis et al. on a suturing task who observed high levels of mental workload by novices who had met their training goals.2 Collectively, these findings show that the spatial secondary task provides an objective index of mental workload, offering a broader picture of laparoscopic skill acquisition.