Spare Attentional Capacity Research Articles

Alcohol increases inattentional blindness when cognitive resources are not consumed by ongoing task demands

RationaleInattentional blindness (IB) is the inability to detect a salient yet unexpected task irrelevant stimulus in one’s visual field when attention is engaged in an ongoing primary task. The present study is the first to examine the impact of both task difficulty and alcohol consumption on IB and primary task performance.ObjectivesOn the basis of alcohol myopia theory, the combined effects of increased task difficulty and alcohol intoxication were predicted to impair task performance and restrict the focus of attention on to task-relevant stimuli. We therefore expected increases in breath alcohol concentration to be associated with poorer primary task performance and higher rates of IB, with these relationships being stronger under hard than easy task conditions.MethodsThis hypothesis was tested in a field study where alcohol drinkers in a local bar were randomly assigned to perform a dynamic IB task with an easy or hard visual tracking and counting task at its core (Simons and Chabris in Perception 28:1059–1074, 1999).ResultsIncreasing the difficulty of the primary task reduced task accuracy but, surprisingly, had no impact on the rate of IB. Higher levels of alcohol intoxication were, however, associated with poorer task performance and an increased rate of IB, but only under easy primary task conditions.ConclusionsResults are consistent with alcohol myopia theory. Alcohol intoxication depletes attentional resources, thus reducing the drinker’s awareness of salient stimuli that are irrelevant to some ongoing primary task. We conclude that this effect was not observed for our hard task because it is more resource intensive, so leaves no spare attentional capacity for alcohol to deplete.

Effects of a novel mental skills curriculum on surgical novices' attention

BackgroundSurgery is very cognitively demanding, particularly for novices. Novices are required to direct full attention on the procedure at hand, and additional demands can lead to cognitive overload. Through extensive practice, experts develop spare attentional capacity (SAC) for simultaneous tasks. However, little effort has been made to enhance novices' SAC. Mental skills may enhance attention management and increase SAC. The purpose of this study was to determine the efficacy of a novel mental skills curriculum (MSC) to enhance novices' attention management. MethodsSixty novice volunteers were randomly stratified to a control or MSC group based on baseline laparoscopic skill and mental skill use (assessed with the Test of Performance Strategies version 2 [TOPS-2]). All participants received laparoscopic training, whereas the MSC group received additional mental skills training. At all sessions, participants completed a secondary task during laparoscopy, which assessed SAC. Participants also completed the D2 Test of Attention and the TOPS-2 attention control subscale, which are valid attention measures. ResultsFifty-five novices completed the study. Both groups displayed significantly improved laparoscopic suturing ability (P < 0.001) and D2 performance (control: P < 0.005, MSC: P < 0.01), but there were no between-group differences in D2 or TOPS attention control scores. However, only the MSC group displayed significantly improved hit rate on the secondary task (P < 0.05). ConclusionsThe novel MSC implemented in this study enhanced surgical novices' SAC compared to controls, and it is clear that this curriculum may be effective at enhancing learners' ability to attend multiple task-relevant stimuli concurrently. Additional study of the impact of this MSC on learners' attentional capacity is currently underway.

Dilution, not load, affects distractor processing.

Lavie and Tsal (1994) proposed that spare attentional capacity is allocated involuntarily to the processing of irrelevant stimuli, thereby enabling interference. Under this view, when task demands increase, spare capacity should decrease and distractor interference should decrease. In support, Lavie and Cox (1997) found that increasing perceptual load by increasing search set size decreased interference from an irrelevant distractor. In three experiments, we manipulated the cue set size (number of cued locations) independently of the display set size (number of letters presented). Increasing the display set size reduced distractor interference regardless of whether the additional letters were relevant to the task. In contrast, increasing the cue set size increased distractor interference. Both findings are inconsistent with the load explanation, but are consistent with a proposed two-stage dilution account.

Conventional versus Moving-Map Navigation Methods

Thirty-eight male and female participants, aged 21 to 50 years, drove to three unfamiliar destinations using three different methods of navigation: Nav, an in-vehicle moving-map and route guidance navigation system; Free, the free use of paper maps or computer printouts, but without access to the navigation system; and Way, which was the same as Free, but with waypoints also provided. Each participant had a minimum of 6 weeks of prior experience using in-vehicle navigation technology. The routes were each designed to sample urban, rural, and highway road categories. Methods were counterbalanced across route and presentation order. An onboard experimenter administered the study. Data were gathered to assess navigational efficiency, workload, and safety-related driving errors. A peripheral detection task was included as a loading task to measure workload and spare attentional capacity objectively; the rating scale of mental effort was included as a subjective measure of mental effort. Use of the navigation system produced better results than either of the two conventional methods in terms of several key metrics related to driver workload, driving errors, and navigational efficiency. These results support the notion that an onboard, moving-map navigation system incorporating route guidance can play a meaningful role in enhancing navigational efficiency and safety for experienced navigation system users. Future research is recommended to examine eye glance and other driver behaviors further, such as lane excursions and headway maintenance, to gain additional insight into the effect of method of navigation on the primary driving task.

Do novices display automaticity during simulator training?

BackgroundThe objective of this study was to investigate whether novices improve their ability to develop multitask (ie, automaticity) with accumulating experience on a simulated laparoscopic task. MethodsIn this prospective study, novices (12 premed students) trained for 4 months in laparoscopic suturing. Simultaneously with suturing, participants performed a visual–spatial secondary task to assess their spare attentional capacity. Trainees were required to achieve expert-derived levels in both suturing (520 score) and the secondary task (target 73%). Their performance was assessed with objective scores, and their ability to multitask during training was examined. ResultsAfter 10 ± 5 hours and 84 ± 41 repetitions, participants demonstrated improvements in their suturing (70%, P < 0.001) and secondary-task performance (16%, P = 0.08) compared with their baseline scores. During the study period, 11 of 12 participants achieved suturing proficiency, but no one achieved secondary-task proficiency. Longer training times correlated with higher secondary-task scores (r = .68, P < 0.02), and participants who performed >100 repetitions (n = 4) achieved higher secondary-task scores (P < 0.03). CommentsThis study provides evidence for improved automaticity at advanced stages of simulator training. Although novices achieve simulator proficiency after relatively short training durations, the attainment of automaticity requires substantially longer training periods. Further study of this concept is warranted and is currently underway.

Miles away: determining the extent of secondary task interference on simulated driving

There is a seemingly perennial debate in the literature about the relative merits of using a secondary task as a measure of spare attentional capacity. One of the main drawbacks is that it could adversely affect the primary task, or other measures of mental workload. The present experiment therefore addressed an important methodological issue for the dual-task experimental approach–that of secondary task interference. The current experiment recorded data in both single- and dual-task scenarios to ascertain the level of secondary task interference in the Southampton Driving Simulator. The results indicated that a spatial secondary task did not have a detrimental effect on driving performance, although it consistently inflated subjective mental workload ratings. However, the latter effect was so consistent across all conditions that it was not considered to pose a problem. General issues of experimental design, as well as wider implications of the findings for multiple resources theory, are discussed.

Redefining simulator proficiency using automaticity theory

Background Automaticity is a characteristic of expertise defined by the ability to perform a task without significant demands on attention. Our objective was to assess whether a visual–spatial task that measures spare attentional capacity would distinguish among individuals with different levels of laparoscopic expertise. Methods The performance of novices (n = 10), surgery residents (n = 9), laparoscopy experts (n = 3), and individuals previously trained (n = 7) to proficiency in laparoscopic suturing on simulators but without operative experience (trained individuals) was measured under dual-task conditions. Participants performed laparoscopic suturing for 10 minutes on a video trainer simulator using the Fundamentals of Laparoscopic Surgery suturing model (primary task) while at the same time they responded to a visual–spatial secondary task. Results Experts and trained individuals outperformed both residents and novices on the suturing task ( P < .001). Although the performance of experts and trained individuals did not differ significantly based on suturing scores, experts achieved higher secondary-task scores ( P < .05). Conclusions A visual–spatial secondary task that assesses spare attentional capacity may help distinguish among individuals of variable laparoscopic expertise when standard performance measures fail to do so. Such automaticity metrics may improve current simulator training and assessment methods and warrants further investigation.

Technology and teen drivers

The rapid evolution of computing, communication, and sensor technology is likely to affect young drivers more than others. The distraction potential of infotainment technology stresses the same vulnerabilities that already lead young drivers to crash more frequently than other drivers. Cell phones, text messaging, MP3 players, and other nomadic devices all present a threat because young drivers may lack the spare attentional capacity for vehicle control and the ability to anticipate and manage hazards. Moreover, young drivers are likely to be the first and most aggressive users of new technology. Fortunately, emerging technology can also support safe driving. Electronic stability control, collision avoidance systems, intelligent speed adaptation, and vehicle tracking systems can all help mitigate the threats to young drivers. However, technology alone is unlikely to make young drivers safer. One promising approach to tailoring technology to teen drivers is to extend proven methods for enhancing young driver safety. The success of graduated drivers license programs (GDL) and the impressive safety benefit of supervised driving suggest ways of tailoring technology to the needs of young drivers. To anticipate the effects of technology on teen driving it may be useful to draw an analogy between the effects of passengers and the effects of technology. Technology can act as a teen passenger and undermine safety or it can act as an adult passenger and enhance safety. Impact on industry: Rapidly developing technology may have particularly large effects on teen drivers. To maximize the positive effects and minimize the negative effects will require a broad range of industries to work together. Ideally, vehicle manufacturers would work with infotainment providers, insurance companies, and policy makers to craft new technologies so that they accommodate the needs of young drivers. Without such collaboration young drivers will face even greater challenges to their safety as new technologies emerge.

The Effects of Modern Navagation on Driver Distraction

This study simulated modern in car navigation with video mapping cues and a low fidelity driving simulator. Forty one participants performed a simulated driving task while either free driving or navigating in conjunction with a standard additional task assessing their spare attentional capacity. The results showed that more lane deviations were made during the navigation than the non navigation task. These findings indicate the greater workload levels associated with the use of video navigation devices. These findings have major implications for driver safety and telematic systems design.

The Effects of Telematics on Driver Distraction

This study used both cellular phones and analogue radio to measure driver distraction and workload in a low fidelity driving simulator. Thirty-four participants performed a simulated driving task while using either a cell phone or a radio in conjunction with a secondary task assessing their spare attentional capacity. The results showed that more lane deviations were made during the cell phone and radio tuning use than both of the pre-allocation and Post-allocation phases. The secondary task errors were also higher during both the cell phone and radio tuning allocation phase than the pre-allocation and post-allocation phases. These findings indicate the greater workload load levels associated with the use of telemetric devices. These findings have major implications for driver safety and telemetric systems design.

Training in virtual environments: transfer to real world tasks and equivalence to real task training

Virtual environments (VEs) are extensively used in training but there have been few rigorous scientific investigations of whether and how skills learned in a VE are transferred to the real world. This research aimed to measure and evaluate what is transferring from training a simple sensorimotor task in a VE to real world performance. In experiment 1, real world performances after virtual training, real training and no training were compared. Virtual and real training resulted in equivalent levels of post-training performance, both of which significantly exceeded task performance without training. Experiments 2 and 3 investigated whether virtual and real trained real world performances differed in their susceptibility to cognitive and motor interfering tasks (experiment 2) and in terms of spare attentional capacity to respond to stimuli and instructions which were not directly related to the task (experiment 3). The only significant difference found was that real task performance after training in a VE was less affected by concurrently performed interference tasks than was real task performance after training on the real task. This finding is discussed in terms of the cognitive load characteristics of virtual training. Virtual training therefore resulted in equivalent or even better real world performance than real training in this simple sensorimotor task, but this finding may not apply to other training tasks. Future research should be directed towards establishing a comprehensive knowledge of what is being transferred to real world performance in other tasks currently being trained in VEs and investigating the equivalence of virtual and real trained performances in these situations.

Learning and Reminiscence as a Function of Target Predictability in a Two-Dimensional Tracking Task

Twenty subjects performed one of two types of a two-dimensional tracking task for two 5-min sessions, separated by a 10-min rest. In task I, both the horizontal and the vertical components of target movement were unpredictable. In task II, the horizontal component of target movement was predictable (sinusoidal), while the vertical movement was unpredictable. There was no change in level of performance throughout the 10 min of practice on task I. For task II's predictable component, there were marked within- and between-session improvements in performance; whereas for the unpredictable component there was only a between-session improvement. It is proposed that, in these tracking tasks, improvement with practice depends on the development of programmed sequences of movement which can only occur for predictable target movements. Only after a rest do these programmed sequences become automatic, releasing spare attentional capacity for improving the performance of any unpredictable components of the task.