Assessing Cognitive Distraction in the Automobile.

OBJECTIVE: The objective was to establish a systematic framework for measuring and understanding cognitive distraction in the automobile. BACKGROUND: Driver distraction from secondary in-vehicle activities is increasingly recognized as a significant source of injuries and fatalities on the roadway. METHOD: Across three studies, participants completed eight in-vehicle tasks commonly performed by the driver of an automobile. Primary, secondary, subjective, and physiological measures were collected and integrated into a cognitive distraction scale. RESULTS: In-vehicle activities, such as listening to the radio or an audio book, were associated with a low level of cognitive workload; the conversation activities of talking to a passenger in the vehicle or conversing with a friend on a handheld or hands-free cell phone were associated with a moderate level of cognitive workload; and using a speech-to-text interfaced e-mail system involved a high level of cognitive workload. CONCLUSION: The research established that there are significant impairments to driving that stem from the diversion of attention from the task of operating a motor vehicle and that the impairments to driving are directly related to the cognitive workload of these in-vehicle activities. Moreover, the adoption of voice-based systems in the vehicle may have unintended consequences that adversely affect traffic safety. APPLICATION: These findings can be used to help inform scientifically based policies on driver distraction, particularly as they relate to cognitive distraction stemming from the diversion of attention to other concurrent activities in the vehicle.

Selective Changes in Complexity of Visual Scanning for Social Stimuli in Infancy.

In the 1st year of life, infants gradually gain the ability to control their eye movements and explore visual scenes, which support their learning and emerging cognitive skills. These gains include domain-general skills such as rapid orienting or attention disengagement as well as domain-specific ones such as increased sensitivity to social stimuli. However, it remains unknown whether these developmental changes in what infants fixate and for how long in naturalistic scenes lead to the emergence of more complex, repeated sequences of fixations, especially when viewing human figures and faces, and whether these changes are related to improvements in domain-general attentional skills. Here we tested longitudinally the developmental changes in the complexity of fixation sequences at 5.5 and 11 months of age using Recurrence Quantification Analysis. We measured changes in how fixations recur in the same location and changes in the patterns (repeated sequences) of fixations in social and non-social scenes that were either static or dynamic. We found more complex patterns (i.e., repeated and longer sequences) of fixations in social than non-social scenes, both static and dynamic. There was also an age-related increase in the length of repeated fixation sequences only for social static scenes, which was independent of individual differences in orienting and attention disengagement. Our results can be interpreted as evidence for fine-tuning of infants' visual scanning skills. They selectively produce longer and more complex sequences of fixations on faces and bodies before reaching the end of the 1st year of life.

Drivers' visual scanning behavior at signalized and unsignalized intersections: A naturalistic driving study in China.

INTRODUCTION: Intersections are the most dangerous locations in urban traffic. The present study aims to investigate drivers' visual scanning behavior at signalized and unsignalized intersections. METHOD: Naturalistic driving data at 318 green phase signalized intersections and 300 unsignalized ones were collected. Drivers' glance allocations were manually categorized into 10 areas of interest (AOIs), based on which three feature subsets were extracted including glance allocation frequencies, durations and AOI transition probabilities. The extracted features at signalized and unsignalized intersections were compared. Features with statistical significances were integrated to characterize drivers' scanning patterns using the hierarchical clustering method. Andrews Curve was adopted to visually illustrate the clustering results of high-dimensional data. RESULTS: Results showed that drivers going straight across signalized intersections had more often glances at the left view mirror and longer fixation on the near left area. When turning left, drivers near signalized intersections had more frequent glances at the left view mirror, fixated much longer on the forward and rearview mirror area, and had higher transition probabilities from near left to far left. Compared with drivers' scanning patterns in left turning maneuver at signalized intersections, drivers with higher situation awareness levels would divide more attention to the forward and right areas than at unsignalized intersections. CONCLUSIONS: This study revealed that intersection types made differences on drivers' scanning behavior. Practical applications: These findings suggest that future applications in advanced driver assistance systems and driver training programs should recommend different scanning strategies to drivers at different types of intersections.

Attentional biases to body shape images in adolescents with anorexia nervosa: an exploratory eye-tracking study.

Body image distortion (BID) plays an important role in the etiology and maintenance of anorexia nervosa (AN). Previous studies of BID in AN showed small biases in visual scanning behavior (VSB) towards images of body shapes. The aim of this study is to investigate biases in VSB when body shape images compete with images with a different theme (social interactions) for subjects׳ attention. When images of thin body shapes (TBS) were presented alongside images of social interactions, AN patients (n=13) spent significantly more time looking at TBSs rather than at social interactions, but controls (n=20) did not. When images of fat body shapes (FBS) were presented alongside images of social interactions, AN patients spent significantly more time looking at FBSs rather than at social interactions, but controls did not. When images of TBSs, FBSs and social interactions were presented alongside each other, AN patients demonstrated a hierarchy in their attention allocation, choosing to spend the most viewing time on TBS images, followed by FBS images and then images with social interactions. Under the three experimental conditions, AN patients demonstrated large biases in their visual scanning behavior (VSB). Biases in VSB may provide physiologically objective measures that characterize patients with AN.