This study was designed to empirically examine the effects of text-messaging on driver distraction. Thirty participants were required to perform a driving simulation task while text-messaging using a cellular phone device. Driving errors as measured by lane deviations, crossing the median, crashes, etc., were recorded and analyzed as a function of the distracter. Physiological measures (EEG) were also recorded during the driving phases to quantitatively measure the participant's level of cortical arousal. It was hypothesized that text-messaging would affect driving ability and the level of cortical arousal. The results indicated higher levels of arousal and a prevalence of the theta frequency (4–7 Hz), which is associated with distractibility as a result of text-messaging activity. In addition, participants showed an increased number of driving errors as a function of text-messaging distractibility. These results have major implications for in-vehicle systems design, traffic safety, and driver attention and workload.

The purpose of the present study was to use a newly-developed measure of reserve attentional capacity to evaluate unitary versus multiple resource theories of attention. Participants performed a primary visual monitoring task and were presented with visual, auditory, and tactile secondary loading tasks. The data indicate that participants maintained performance on the primary task, as instructed, and performed the secondary task with any remaining attentional reserve capacity. A significant difference was found on the basis of secondary task modality, wherein performance on the visual secondary task was significantly worse than that of secondary auditory and tactile tasks. This result was additionally supported by scores on a subjective workload questionnaire. Although the data do not preclude interpretation in terms of a unitary resource model, data trends offer potential support for a multiple resource model.

There are a variety of driver distractions that negatively affect driver workload and performance. These distractions range attempting to light a cigarette, and putting on make-up, to eating or drinking, tuning the radio, using a cellular phone, or using an in-vehicle navigation system. Of particular present interest are the distracting effects of telematic devices, which include traffic information systems, telecommunication, intelligent aid and control, and navigational systems. These devices can now be found on-board various types of U.S. and foreign automobiles. Despite having many potential benefits, there are also several behavioral problems resulting from poor use of these devices. The present research was designed to investigate the deleterious effects of telematics on driver performance. It was hypothesized that all the telematic systems used in this study would degrade driver performance and increase workload. A mixed-model factorial design (2x3) was used, with telematics being a between-subject factor and allocation phase a within-subject factor (repeated measures). All participants were required to drive three, four-minute simulated (pre, during, and post) allocation phases. In the preallocation phase, participants were required to drive while performing a secondary counting task, (counting and responding to a series of randomly presented visual signals). During the allocation phase, participants were required to drive and perform the secondary counting task while either talking on the phone or tuning a radio (distractibility task). In the post-allocation phase, participants were required to drive while performing the secondary counting task. Data from the counting task (number of correct, wrong, and misses) and driving errors (collisions, crossing the median, leaving the road, maintaining the speed limit, and lane deviations) were recorded and statistically analyzed. Thirty-four participants (nine males and 25 females) from the University of Central Florida participated in this study. A series of analyses of variance (ANOVA) were conducted to test for the effects of telematics and workload on each of the dependent measures. A significant main effect of phase on lane deviations was observed, F(2, 64) = 10.58, p < .001, indicating that more lane deviations were made during the cell phone and radio tuning use (M = 9.14) than during both of the pre-allocation (M = 4.14) and post-allocation (M = 5.88) phases. ANOVA also yielded a significant main effect of phase on crossing the median, F(3, 68) = 4.63, p < .05, indicating that more crossings were made during the allocation phase (M = 5.05) than during the pre-allocation (M = 3.05) and post-allocation (M = 4.47) phases. Similarly, the results also showed a significant effect of phase on the distraction task performance, F(2, 64) = 5.70, p < .01, indicating that more errors were made during the allocation phase (M = 6.50) than during the pre-allocation (M = 4.50) and the post-allocation (M = 3.38) phases. PROCEEDINGS of the Second International Driving Symposium on Human Factors in Driver Assessment, Training and Vehicle Design 68 The present findings indicate that both cellular phone and radio systems are capacity demanding. The counting task results demonstrate the increased level of workload associated with these telematic devices. In addition, driving performance errors were also higher for both the cellular phone and the radio systems. Our findings suggest the need to regulate the use of such devices in order to avoid overloading the driver’s attentional spare capacity.

The current research investigated the effects of aging on driving performance. Perceptual measures included far and near point acuity, stereopsis, a measure of lateral and vertical phoria, color vision; and spatial contrast sensitivity. Cognitive functioning was examined using the Useful-Field-of-View (UFOV) Test. In addition, each driver completed a Driving Habits Questionnaire (DHQ). Although older drivers tended to have fewer collisions and exhibited better adherence to speed limits in a simulated driving task than did younger drivers, older drivers appear to be at a greater risk of having a collision, resulting from degraded divided and selective attention compared to the younger drivers.

This paper introduces some of the research work on the effects of telematics, in this case a radio system, on driver's performance. Twenty-four undergraduate students participated in a series of simulated driving scenarios. In the pre- and post-allocation phases, all participants were required to drive two-four minute phases to establish their baseline scores. In the allocation phase, they were required to tune to a series of local radio stations while performing the same driving scenarios. The results indicated that participants committed more driving errors and violations during the radio-tuning phase than any of the other pre- and post-allocation phases. These errors were manifested in an increased number of crossing the median marking, leaving the roadway, and/or lane deviation. The implications of these results are also outlined in the present paper.

The utilization of head-mounted displays (HMDs) in high-end applications such as medical, engineering, and scientific visualization necessitates that the position of objects be rendered accurately and precisely. Accuracy and precision of rendered depth for near-field visualization were measured in a custom-designed bench prototype HMD. Experimental results were compared to theoretical predictions established from a computational model for rendering and presenting virtual images by Robinett and Rolland (1992). Such a theoretical model provided the necessary graphics transformations required so that rendered virtual objects be perceived at the rendered depth in binocular HMDs, Three object shapes of various sizes were investigated under two methodologies: the method of constant stimuli modified for random size presentation and the method of adjustments, Results show a 2 mm and an 8 mm performance for the accuracy and the precision of rendered depth in HMDs, respectively, Results of the assessment of rendered depth in HMDs for near-field visualization support employing the method of adjustments over the method of constant stimuli whether or not the method of constant stimuli is modified for random size presentation.

This research examined perceptual and cognitive functioning as a function of age. The results obtained are presented in this report. These results are now being analyzed and in a future report will be related to recommendations for training, rehabilitation, and automotive design, as well as assessment.

The goal of this research was to investigate the effects of foveal load on sensitivity in the peripheral visual field. Foveal load was manipulated by comparing the simple fixation of a cross vs. a first-order (i.e., rate) compensatory tracking task. Peripheral sensitivity was determined simultaneously for light flashes presented at different eccentricities along the horizontal meridian. The effects of training on the task were also evaluated in terms of changes in peripheral sensitivity. In general, the results showed no losses in peripheral sensitivity or a "tunnel vision" effect under the experimental conditions employed. These results are contrary to data obtained by previous investigators. Reasons for these findings are discussed.

Technological advances have signi-ficantly altered the nature of the man-machine inter-face. Notable changes include: 1) a redefinition of the role of the human from that of a manual operator to a monitor/manager of complex systems; and 2) the availability of large amounts of data, presented or updated at rapid rates. As a result of such changes, the human operator must monitor, integrate, evaluate, and utilize continually changing information from a large number of spatially separated displays. Such demands require complex scanning patterns among numerous displays, and maintaining large amounts of information in working memory. These requirements and demands often overload the human's limited processing capabilities, and lead to degraded performance and increased probability of error. One possible solution to this propagation of displays and consequent information overload is to make more efficient use of human visual capabilities by offloading some types of information from foveal vision to peripheral vision. If appropriate types of information are presented to each aspect of vision (foveal and peripheral), then the human operator's bandwidth of information intake may be usefully increased. However, significant issues must be addressed before attempts are made to design peripheral displays. Such issues may be grouped into three categories: 1) determine the characteristics of peripheral vision relevant to display design (e.g., luminance sensitivity, contrast sensitivity, and acuity); 2) determine the characteristics of peripheral information processing (e.g., the costs and benefits of covert orienting of attention, the effects of foveal load on peripheral processing and vice-versa, and events in peripheral vision that cause a saccade); and 3) determine what types of information structure provide useful information in peripheral vision, which would indicate what types of information should be displayed in peripheral vision. The answers to these issues will provide data that may help determine whether it is feasible to display useable information to both foveal and peripheral vision, and provide guidelines for the design of peripheral displays. The purpose of this symposium is to address theoretical and applied issues of peripheral vision. The description and evaluation of the properties and characteristics of peripheral vision will serve as fundamental knowledge in determining the feasibility and design of peripheral displays. The symposium will be empirical in nature, with the participants presenting experimental data relevant to the above issues.

The main objective of the research was to investigate the effects of load on peripheral sensitivity in the visual field. Foveal load was varied by using simple fixation of a vs. a first-order (rate) compensatory tracking task. Peripheral sensitivity was determined simultaneously for light flashes located at different eccentricities along the horizontal meridian. The effects of training on the tracking task were also examined. In general, the results showed no losses in peripheral sensitivity under the experimental conditions employed, contrary to data from previous studies.

Recent interest in the importance of visual displays within specified flight simulations and scenarios has led to increased emphasis on the identification of pertinent cues within these displays. Through the identification of these cues and their usage in altitude estimation, more effective simulation and hence training programs can be developed. The present explanatory study investigated the use of a psychophysical methodology in the evaluation of aerial perspective as a possible cue in altitude estimation. Specifically the effects of two levels of aerial perspective (present and reduced) and flight experience on estimations were examined. Based on the linear functions of log estimated vs. log actual altitude, differences were found between levels of flight experience in the aerial perspective-present condition. Subjective responses suggest that individuals are aware of the presence/absence of haze conditions and this information influences their altitude estimations.

A multiplication circuit that can facilitate generation of variable-contrast luminance gratings via a microcomputer is described. The circuit is inexpensive and easy to build.

Growing emphasis on simulation of low altitude and air-to-air tactical scenarios has greatly increased the requirement for simulator visual systems capable of providing the pilot high-fidelity out-of-the-cockpit cues. Evaluation of visual system performance through simulator flying studies has been the primary measure of system quality. Such studies can be costly and time consuming, and often they provide equivocal results. The present set of experiments was conducted to investigate the use of psychophysical measurement methodology to provide a quick, low-cost evaluation of the altitude cueing effectiveness of simulator visual displays. Experiment I examined altitude perception in several visual environments. Experiment II was a validation effort, in which flying performance was evaluated in selected visual environments. In Experiment I pilots made altitude estimates based on static and dynamic presentations of visual displays containing texture and varying sizes of 3-dimensional objects. Best-fitting power functions were used to relate perceived altitude to actual altitude. In Experiment II Air force pilots flew the Advanced Simulator for Pilot Training F-16 through five selected visual environments at 600 kt and 150 ft AGL. Reliable difference were found as a function of display variables. In environments which provided strong altitude cues, pilots were able to fly very close to the designated altitude. In environments which provided poorer cues, pilots flew substantially above designated altitude.