Eye movements and hazard perception in active and passive driving

ABSTRACT

Differences in eye movement patterns are often found when comparing passive viewing paradigms to actively engaging in everyday tasks. Arguably, investigations into visuomotor control should therefore be most useful when conducted in settings that incorporate the intrinsic link between vision and action. We present a study that compares oculomotor behaviour and hazard reaction times across a simulated driving task and a comparable, but passive, video-based hazard perception task. We found that participants scanned the road less during the active driving task and fixated closer to the front of the vehicle. Participants were also slower to detect the hazards in the driving task. Our results suggest that the interactivity of simulated driving places increased demand upon the visual and attention systems than simply viewing driving movies. We offer insights into why these differences occur and explore the possible implications of such findings within the wider context of driver training and assessment.     

Suppression of brain activity related to a car-following task with an auditory task: An fMRI study

Driving a car in daily life involves multiple tasks. One important task for safe driving is car-following, the interference of which causes rear-end collisions: the most common type of car accident. Recent reports have described that car-following is hindered even by hands-free mobile telephones. We conducted functional MRI with 18 normal volunteers to investigate brain activity changes that occur during a car-following task with a concurrent auditory task. Participants performed three tasks: a driving task, an auditory task, and a dual task in an fMRI run. During the driving task, participants use a joystick to control their vehicle speed in a driving simulator to maintain a constant distance from a leading car, which moves at varying speed. Language trials and tone discrimination trials are presented during the auditory task. Car-following performance was worse during the dual task than during the single-driving task, showing positive correlation with brain activity in the bilateral lateral occipital complex and the right inferior parietal lobule. In the medial prefrontal cortex and left superior occipital gyrus, the brain activity of the dual task condition was less than that in the single-driving task condition. These results suggest that the decline of brain activity in these regions may induce car-following performance deterioration.     

The Swedish Hayling task,and its relation to working memory,verbal ability,and speech‐recognition‐in‐noise

Cognitive functions and speech‐recognition‐in‐noise were evaluated with a cognitive test battery, assessing response inhibition using the Hayling task, working memory capacity (WMC) and verbal information processing, and an auditory test of speech recognition. The cognitive tests were performed in silence whereas the speech recognition task was presented in noise. Thirty young normally‐hearing individuals participated in the study. The aim of the study was to investigate one executive function, response inhibition, and whether it is related to individual working memory capacity (WMC), and how speech‐recognition‐in‐noise relates to WMC and inhibitory control. The results showed a significant difference between initiation and response inhibition, suggesting that the Hayling task taps cognitive activity responsible for executive control. Our findings also suggest that high verbal ability was associated with better performance in the Hayling task. We also present findings suggesting that individuals who perform well on tasks involving response inhibition, and WMC, also perform well on a speech‐in‐noise task. Our findings indicate that capacity to resist semantic interference can be used to predict performance on speech‐in‐noise tasks.     

Effects of verbal and spatial-imagery tasks on eye fixations while driving

The consequences of performing verbal and spatial-imagery tasks on visual search when driving were studied. Twelve participants drove 84 km on 2 highways and 2 roads. On each route, they performed 2 verbal tasks and 2 spatial-imagery tasks while their eye movements were recorded. The same results were repeated on all routes. Pupillary dilation indicated similar effort for each task. Visual functional-field size decreased horizontally and vertically, particularly for spatial-imagery tasks. Compared with ordinary driving, fixations were longer during the spatial-imagery task. With regard to driving performance, glance frequency at mirrors and speedometer decreased during the spatial-imagery task. Results are interpreted in terms of multiple attention-resource theories; implications of internal distractions on road safety are discussed in terms of possible impairment in relevant information processing.     

Driving on familiar roads: Automaticity and inattention blindness

This paper describes our research into the processes that govern driver attention and behavior in familiar, well-practiced situations. The experiment examined the effects of extended practice on inattention blindness and detection of changes to the driving environment in a high-fidelity driving simulator. Participants were paid to drive a simulated road regularly over 3 months of testing. A range of measures, including detection task performance and driving performance, were collected over the course of 20 sessions. Performance from a yoked Control Group who experienced the same road scenarios in a single session was also measured. The data showed changes in what drivers reported noticing indicative of inattention blindness, and declining ratings of mental demand suggesting that many participants were “driving without awareness”. Extended practice also resulted in increased sensitivity for detecting changes to road features associated with vehicle guidance and improved performance on an embedded vehicle detection task (detection of a specific vehicle type). The data provide new light on a “tandem model” of driver behavior that includes both explicit and implicit processes involved in driving performance. The findings also suggest reasons drivers are most likely to crash at locations very near their homes.     

Effects of primary task predictability and secondary task modality on lane maintenance

The objective of this work was to investigate the effects of auditory and visuo-spatial secondary tasks on variability in lane position in predictable and unpredictable driving conditions. Sixty-six participants drove a simulated vehicle. Predictability was manipulated by adding wind gusts, and the secondary task load by either an auditory task (Experiment 1) or a visuo-spatial task (Experiment 2). Results demonstrated that in the predictable driving condition, lane position variability decreased when auditory secondary task load was given, but it was not affected by visuo-spatial secondary task load. In the unpredictable driving condition; however, while the auditory secondary task load did not affect lane position variability, visuo-spatial secondary task load increased it. The data suggests that the effects of cognitive load on lane maintenance may depend on the type of the secondary task beside predictability of primary task.     

Task-induced fatigue states and simulated driving performance

States of fatigue are implicated in driver impairment and motor vehicle accidents. This article reports two studies investigating two possible mechanisms for performance impairment: (1) loss of attentional resources; and (2) active regulation of matching effort to task demands. The first hypothesis predicts that fatigue effects will be accentuated by high task demands, but the second hypothesis predicts that fatigue effects will be strongest in "underload" conditions. In two studies, drivers performed a stimulated driving task, in which task demands were manipulated by varying road curvature. In a "fatigue induction" condition, the early part of the drive was occupied by performance of a demanding secondary task concurrently with driving, after which the concurrent task ceased. Post-induction driving performance was compared with a control condition in which drivers were not exposed to the induction. In both studies, the fatigue induction elicited various subjective fatigue and stress symptoms, and also raised reported workload. Fatigue effects on vehicle control and signal detection were assessed during and after the fatigue induction. The fatigue induction increased heading error, reduced steering activity, and, in the second study, reduced perceptual sensitivity on a secondary detection task. These effects were confined to driving on straight rather than on curved road sections, consistent with the effort regulation hypothesis. The second study showed that fatigue effects were moderated by a motivational manipulation. Results are interpreted within a control model, such that task-induced fatigue may reduce awareness of performance impairment, rather than reluctance or inability to mobilize compensatory effort following detection of impairment.     

Central interference in driving: is there any stopping the psychological refractory period?

ABSTRACT— Participants attempted to perform two tasks concurrently during simulated driving. In the choice task, they responded either manually or vocally to the number of times a visual or auditory stimulus occurred; in the braking task, they depressed a brake pedal in response to the lead car's brake lights. The time delay between the onset of the tasks' stimuli, or stimulus onset asynchrony (SOA), was varied. The tasks were differentially affected by the manipulations. Brake reaction times increased as SOA was reduced, showing the psychological refractory period effect, whereas the choice task showed large effects of the stimulus and response modalities but only a small effect of SOA. These results demonstrate that a well-practiced "simple" task such as vehicle braking is subject to dual-task slowing and extend the generality of the central-bottleneck model.     

Cognitive consequences of congenital deafness

Comparing congenitally deaf children with hearing children on a variety of information processing tasks provides a natural test of the developmental consequences accompanying the long term loss of a particular sensory input. In this experiment, two sequential and two spatial tasks were used to evaluate the way deaf and hearing individuals process these different types of information. When deaf students were asked to recall the order of a string of lights, they performed as well as hearing students. Deaf students were at a significant disadvantage, however, when processing sequentially presented digits. Deaf students performed as well as hearing students on two complex, standardized spatial tasks. The loss of a major sensory modality had minimal effect on three of the four tasks investigated in the present study. Explanations for the single task with a performance differential are considered.     

The impact of age on useful visual field deterioration and risk evaluation in a simulated driving task

The primary goal of this study is to evaluate whether the driver can estimate his performance and the deterioration of his state of alertness during a simulated driving task. The second goal is to study the relation between useful visual field (UVF) deterioration and the capacity to estimate performance in a visual task and the decrease of level of alertness as a function of age. In our experiment, two groups of subjects: 10 drivers between 21 and 34 years old and nine drivers between 46 and 57 years old were required to follow a vehicle in a simulated road traffic situation for 2 hours. In addition, the driver had to detect the change of colour of a signal located in the central part of his visual field or a peripheral signal appeared on the rear light of one of the vehicles in the traffic. The analysis of data collected during this visual task confirms that UVF deteriorates with the duration of the driving task and with the driver's age. The analysis of subjective data related to the state of alertness highlights an effect both of age and of the moment when this self-evaluation was carried out. However, self-evaluation of the subject's performance does not depend on driver's age. Finally, the study shows that the correlation between objective data (performance of visual task) and subjective data (state of drowsiness and self-evaluation of performance of the visual task) is low, and the implications with regard to road safety are discussed.     

The effect of the emotional state on driving performance in a simulated car-following task

Emotion is an important factor that influences driving behavior, but the mechanism is unclear. This research explored the effect of the emotional state on simulated driving behavior. Thirty-five licensed drivers participated in this study and completed a car-following task. The angry, happy and neutral states were manipulated during the task. The participants’ driving performance and risk perception were recorded under each emotional state. Trait anger and driving experience were also measured to explore the possible mediating effect. The results showed that the drivers in an angry or happy emotional state tended to maintain less time to collision and take a longer time to brake while following a lead vehicle than the drivers under the neutral condition, suggesting that drivers in emotional states are more dangerous those in neutral states. Moreover, the happy state rendered the drivers more dangerous, which manifested as a lower perceived accident risk than that among the drivers in the angry and neutral states. More specifically, experienced drivers in happy states performed worse with respect to vehicle lateral position control. Recommendations and implications for safety education and further research are discussed.     

Towards testing auditory–vocal interfaces and detecting distraction while driving: A comparison of eye-movement measures in the assessment of cognitive workload

Recently, there has been a growing need among researchers to understand the problem of cognitive workload induced by auditory–verbal–vocal tasks while driving in realistic conditions. This is due to the fact that we need (a) valid methods to evaluate in-vehicle electronic devices using voice control systems and (b) experimental data to build more reliable driver state monitoring systems. In this study, we examined the effects of cognitive workload induced by the delayed digit recall task (n-back) while driving. We used a high-fidelity driving simulator and a highway scenario with moderate traffic to study eye movements in realistic driving conditions. This study included 46 participants, and the results indicate that a change in pupil size is most sensitive for measuring changes in cognitive demand in auditory–verbal–vocal tasks. Less sensitive measures included changes in fixation location and blink rate. Fixation durations and the driving performance metrics did not provide sensitive measures of graded levels of cognitive demand.     

Anticipatory and control processes in the interaction with secondary tasks while driving

The paper describes an experiment where anticipatory processes in the interaction with secondary tasks while driving could be explicitly identified and contrasted to control processes during the engagement in the secondary task. A special experimental set-up in a driving simulator environment was created that allows drivers to deliberately decide whether they want to be distracted or not depending on the driving situation and the expected development of that situation. As indicators for a situation-adaptive interaction with secondary tasks parameters from driving behaviour, secondary task performance and visual behaviour were analyzed. A study with 24 test drivers revealed that drivers are, in general, able to interact with a secondary task in a situation-aware manner. For example, drivers rejected more secondary tasks in already highly demanding situations or tried to delay the beginning of the task. During secondary task performance drivers observed the situational development with short control glances back to the road and adapted their speed. The analysis of driving errors revealed that rejecting a task in an already highly demanding driving situation is an effective strategy to maintain an adequate level of driving safety. However, some critical factors were identified that might hinder the driver from executing such strategies. Several recommendations for supporting the driver on this issue are given.     

The effects of motion on in-vehicle touch screen system operation: A battle management system case study

The use of in-vehicle touch screen devices is currently common in both military and civilian vehicles; despite this, the effects of motion on touch screen device operation within vehicles remains largely unexplored. This article describes a study that examined, using driving simulation, the influences of motion on performance, workload and usability when using a touch screen in-vehicle battle management system. Acting in the role of battle management system operator, 20 participants undertook four simulated drives, two under high motion (representative of an unsealed road) and two under normal motion (representative of a sealed road), whilst performing various battle management tasks. In the high motion condition, lower accuracy and longer task completion times were found, along with greater levels of subjective and physiological workload and lower levels of perceived device usability, when compared to the normal motion condition. The findings indicate that, compared to normal motion, the high motion condition impaired key aspects of battle management system operation. In closing, the importance of considering motion and its effects during touch screen system design is discussed.     

Driving without awareness: The effects of practice and automaticity on attention and driving

This research examined the development of proceduralised “driving without awareness” in a driving simulator by paying participants to drive a simulated road regularly over 12 weeks of testing. This longitudinal research paradigm is a significant departure from previous studies which have examined drivers in a conscious attentional mode using short experimental sessions or cross-sectional designs comparing expert and novice performance. During each session, participants took two “trips” on the simulated road; sometimes travelling on a “to and from” journey on one half of the road, sometimes traversing the entire road in one direction. A range of measures, including driving performance, vehicle detection, perceptual speed regulation, and hazard reactions were collected. The results showed the development of driving patterns and changes in object detection performance indicative of proceduralised driving. Speed and lane position variability quickly decreased with practice, as did participants’ subjective experiences of driving difficulty. Performance on an embedded detection task appeared to become a proceduralised part of the driving task, becoming highly efficient in later stages of the experiment. The changes in attentional focus and driving performance over time provide new light on previous research findings and allow us to critically re-examine several established models of driver behaviour.     

Is Semantics Affected by Missing a Critical Period? Evidence from the Persian Deaf

The present study aims to explore the semantic knowledge of a group of Iranian deaf individuals who, due mainly to auditory deprivation did not acquire language normally in early years of their life. The participants were ten deaf and a matched number of hearing individuals as control group. A test of five tasks was administrated to assess their knowledge of vocabulary, collocation, semantic categorizations, semantic features, and proverbs. Although the results indicated a significant difference between the deaf and the hearing group, a between- group comparison of each task revealed no significant difference between the deaf and hearing participants in the number of errors in vocabulary, collocations, semantic categorization, and semantic features. The only task in which deaf participants did significantly worse than the control group was that of proverbs. Therefore, it could be argued that, language deprivation in early childhood does not have the same effect on different components of our linguistic knowledge and that the acquisition of semantics may well continue beyond puberty.     

Looking and thinking when driving: The impact of gaze and cognitive load on steering

Driving around bends at high speeds is a task performed by many on a daily basis but the underlying mechanisms of steering control remain largely unknown. Previous research has shown that when steering, gaze direction can be a critical component of success. However, with increased use of in-vehicle information systems (IVIS), there is growing competition over the same resources that are needed to steer (gaze as well as associated attentional resources). Although it can be argued that locomotor steering is an automatic task that can be performed without recourse to conscious “cognitive” control, much simpler locomotor-related tasks, such as judging one’s heading, have been shown to be affected by concurrent attentional tasks (Wann, Swapp, & Rushton, 2000). Here we examined whether an attentional task placed at an offset fixation point influenced concurrent steering performance along a computer simulated road. The experiments either used gaze-fixation points that had similar properties to real-world road signs (i.e. moved relative to the vehicle) or were more akin to IVIS (i.e. fixed to the vehicle). Results showed that gaze fixation eccentric to future path caused systematic steering biases. The degree or type of cognitive load did not change the degree of steering bias, but there was some evidence of decreased lane variability when viewing the IVIS-type displays. No differences in steering performance were found between the different types of cognitive task. We conclude that where you look is critical for safe driving, and IVIS-type displays might make drivers more susceptible to cognitive interference.     

Deterioration of the phonological processing skills in adults with an acquired severe hearing loss

Phonological processing was examined in a group of individuals with an acquired severe hearing loss and compared to a group of matched normal hearing individuals. The hearing-impaired group was significantly slower and less accurate when performing a visual rhyme-judgement task, and produced fewer rhyming word pairs on a rhyme-generation task than the normal hearing group. In contrast, the hearing-impaired group performed on a par with the normal hearing group on verbal working memory tasks. It is concluded that specific aspects of the phonological system deteriorate in this population as a function of auditory deprivation. In particular, the phonological representations are impaired and this impairment also affects the ability to rapidly perform phonological operations (i.e., analyse and compare). In contrast, phonological processing involved in verbal working memory is preserved in this population.     

Measurement of auditory cues in drivers' distraction

A driving simulator was used to examine the effects on driving performance of auditory cues in an in-vehicle information search task. Drivers' distraction by the search tasks was measured on a peripheral detection task. The difficulty of the search task was systematically varied to test the distraction caused by a quantified visual load. 58 participants completed the task. Performance on both search tasks and peripheral detection tasks was measured by mean response time and percent error. Analyses indicated that in-vehicle information search performance can be severely degraded when a target is located within a group of diverse distractors. Inclusion of an auditory cue in the visual search increased the mean response time as a result of a change in modality from auditory to visual. Inclusion of such an auditory cue seemed to influence distraction as measured by performance on the peripheral detection task; accuracy was lower when auditory cues were provided, and responses were slower when no auditory cues were provided. Distraction by the auditory cue varied according to the difficulty of the search task.     

Strategic changes in task performance in simulated car driving as an adaptive response to task demands

Car drivers appear to reduce their driving speed in high task demand situations. Summala's [Safety Sci. 22 (1996) 103–117]; [in: J.A. Rothengatter, & E. Carbonell Vaya (Eds.), Traffic and Transport Psychology: Theory and Application, Pergamon, Oxford, 1997, pp. 41–52] model of behavioural adaptation (MBA) also assumes that drivers increase speed in low task demand situations or attend to additional tasks more. The present study investigated the relation between driving speed and task demands in simulated driving. Participants were observed under three speed conditions, driving fast, driving as if taking a driving test, and following a fast-driving car. The same route was driven twice under each of these speed conditions: once with and once without the concurrent performance of an auditory short-term memory task. All other things being equal, driving fast required more effort than driving more slowly, which was not compensated for by better memory performance. This refutes one assumption of the MBA. When following a fast-driving car, participants invested less effort than when driving fast. As auditory route guidance messages were embedded within the memory task, participants were forced to attend the memory task in all rides of the Fast and Accurate conditions, but not in the Car Following conditions. This can also explain why the memory task had no effect on cognitive effort. It is concluded that car drivers prioritise their task goals.