Drew M. Morris

Lane heading difference: An innovative model for drowsy driving detection using retrospective analysis around curves

Driving while sleepy is a serious contributor to automobile accidents. Previous research has shown that drowsy drivers produce systematic errors (variability) in vehicle behavior which are detectable using vehicle monitoring technology. The current study developed a new methodological approach using a vehicle heading difference metric to detect drowsy driving more effectively than other more commonly used methods. Twenty participants completed a driving scenario as well as several measures of fatigue in five testing sessions across a night of sleep deprivation. Each simulated highway driving session lasted 20 min, and was analyzed for lateral lane position variability and vehicle heading difference variability with two statistical methods. Fatigue measures monitored reaction time, attention, and oculomotor movement. The results showed that examining lane heading difference using the absolute value of the raw data detected driving variability better across the night than other statistical models. The results from the fatigue measures indicated an increase in reaction time and response lapses, as well as a decrease in oculomotor reactivity across the night. These results suggest that in fatigued drivers the statistical model using the absolute value of lane heading could be an improved metric for drowsy driving detection that could accurately detect detriments in driving ability at lower levels of fatigue.

Interactions between sleep habits and self-control

Good sleep habits and effective self-control are important components of successful functioning. Unfortunately chronic sleep loss and impaired self-control are common occurrences for many individuals which can lead to difficulty with daily self-control issues such as resisting impulses and maintaining attentive behavior. Understanding how self-control is depleted and how good sleep habits may help replenish and maintain the capacity for self-control is an important issue. A sleep-deprived individual who has expended the necessary resources for self-control is at an increased risk for succumbing to impulsive desires, poor attentional capacity, and compromised decision making. To date, few studies have investigated how sleep and self-control are inter-related. The goal of this mini-review is to explore the intersection between sleep habits and self-control and encourage researchers to focus on a new area of research that integrates what are at present largely separate areas in psychology and human neurosciences.

The cold driver: Cold stress while driving results in dangerous behavior

Cool vehicle cabin temperatures can induce short-term non-hypothermic cold stress. The current study created a cold condition to examine the impact of cold stress on driving behavior. Forty-four participants drove a high-fidelity driving simulator during a thermal neutral or local torso cooled condition. Participants performed additional tasks to assess attention, psychomotor vigilance, and manual dexterity. Skin temperature was significantly lower in the cold condition while internal temperature was unaffected. Participants who had higher subjective ratings of cold followed lead vehicles closer and started to brake later. Participants in the cold condition followed the lead car 22% (0.82s) closer and started braking 20% (2.35s) later when approaching a stop sign during the car-following task. No change in attention, psychomotor vigilance, or dexterity was observed. The current results suggest that cold environmental conditions can contribute to dangerous driving behaviors. Measures of cold perception were also shown to predict changes in driving behavior.

Decreasing Sedentary Behavior: Effects on Academic Performance, Meta-Cognition, and Sleep

There is growing interest in using activity workstations as a method of increasing light physical activity in normally sedentary environments. The current study (N = 117) compared the effects of studying in college students while slowly pedaling a stationary bike with a desktop with studying at traditional desks across 10 weeks in an academic semester. The students were assigned to study either on the stationary bike or at a traditional desk located in the campus library for a minimum of 2 h a week. During the 10 weeks, the students studied for tests or worked on other required academic activities while working at their assigned desk. In addition, the participants completed a pre survey, weekly surveys, and a post survey. We found that although students studying at the traditional desks reported more ease of studying and more effective studying than those using the stationary bikes, the two groups performed equally well on tests in an introductory psychology course. Moreover, the students using the traditional desks reported a decrease in sleep quality later in the semester while those using the activity workstation reported stable levels of sleep quality. The current results indicate that activity workstations could be implemented in university settings to encourage light physical activity without negatively affecting academic performance while providing possible long-term health and well-being benefits. Furthermore, the results suggests that activity workstations could be a means of combating sedentary behavior in environments where individuals are expected to sit either while waiting (e.g., doctors waiting rooms, airports) or when completing a necessary task (e.g., the workplace, educational settings).

Performance awareness: Predicting cognitive performance during simulated shiftwork using chronobiological measures

Physiological tracers of circadian rhythms and a performance awareness index were examined as predictors of cognitive performance during two sleep deprivation conditions common to occupational shiftwork. Study 1: Thirty-three sleep-deprived participants completed a simulated nightshift. Study 2: Thirty-two partially sleep-deprived participants completed a simulated dayshift. A standardized logic test was used to measure cognitive performance. Body temperature and heart rate were measured as chronobiological indices of endogenous circadian rhythms. Performance awareness was calculated as a correlation between actual and perceived performance. These studies demonstrated a parallelism between performance awareness and the circadian rhythm. Chronobiological changes were predictive of performance awareness during the simulated nightshift but not dayshift. Only oral temperature was a significant independent predictor. Oral temperature predicted an individuals awareness of their own performance better than their own subjective awareness. These findings suggest that using circadian rhythms in applied ergonomics may reduce occupational risk due to low performance awareness.

Electrodermal Response and Automation Trust during Simulated Self-Driving Car Use

The integration of self-driving vehicles may expose individuals with health concerns to undue amounts of stress. Psychophysiological indicators of stress were used to determine changes in tonic and phasic stress levels brought about by a high-fidelity autonomous vehicle simulation. Twenty-eight participants completed one manual driving task and two automated driving tasks. Participants reported their subjective level of trust in the automated systems using the Automation Trust Survey. Psychophysiological stress was indexed using skin conductance and trapezius muscle tension. Results indicate that users show more signs of physiological stress when the vehicle drives autonomously than when the users is in control. Results also indicate that users show an additional increase in stress when the user reports low trust in the autonomous vehicle. These findings suggest that health-care professionals and manufactures should be aware of additional stress associated with self-driving technology.

Task-dependent cold stress during expeditions in Antarctic environments

ABSTRACT This study seeks to understand the degree of body cooling, cold perception and physical discomfort during Antarctic tour excursions. Eight experienced expedition leaders across three Antarctic cruise voyages were monitored during occupational tasks: kayaking, snorkelling and zodiac outings. Subjective cold perception and discomfort were recorded using a thermal comfort assessment and skin temperature was recorded using a portable data logger. Indoor cabin temperature and outdoor temperature with wind velocity were used as measures of environmental stress. Physical activity level and clothing insulation were estimated using previous literature. Tour leaders experienced a 6°C (2°C wind chill) environment for an average of 6 hours each day. Leaders involved in kayaking reported feeling colder and more uncomfortable than other leaders, but zodiac leaders showed greater skin temperature cooling. Occupational experience did not predict body cooling or cold stress perception. These findings indicate that occupational cold stress varies by activity and measurement methodology. The current study effectively used objective and subjective measures of cold-stress to identify factors which can contribute to risk in the Antarctic tourism industry. Results suggest that the type of activity may moderate risk of hypothermia, but not discomfort, potentially putting individuals at risk for cognitive related mistakes and cold injuries.

Antarctica Cold Stress Risks during Occupational and Leisure Activities

A growing tourism industry in Antarctica raises concerns about occupational health risks. Risks associated with cold exposure were explored during three voyages of an Antarctic cruise vessel. Eight expedition leaders were monitored for skin temperature, physical activity, and subjective cold perception and comfort during 35 excursions. Results showed that those participants involved in zodiac boat sightseeing excursions with low activity and high wind chill had significantly greater body cooling than other participants involved in kayaking or snorkeling (down 2°F). However those involved in kayaking reported the greatest cold awareness and subjective cold discomfort. Prior experience with the Antarctic occupations was not indicative of cold tolerance. Findings suggest that the type of activity engaged in will vary the amount of occupational risk associated with cold exposure. This study is one of the first of its kind to provide pragmatic information for the occupational safety sector of the Antarctic tourism industry.A growing tourism industry in Antarctica raises concerns about occupational health risks. Risks associated with cold exposure were explored during three voyages of an Antarctic cruise vessel. Eight...

Psychological Response not Physiological Response Predicts Aggression behind the Wheel during Cold Stress

Cold environments alter human behavior and limit performance through cold stress. Driving is commonly performed during cold winter months when vehicle cabin temperatures induce short-term cold stress. Skin temperature was experimentally manipulated to study the impact of cold stress on driving behavior. Forty-four participants drove a high-fidelity driving simulator during a thermal neutral or cooled condition. Results showed that participants who had higher subjective ratings of cold followed lead vehicles closer and applied brakes harder. Participants in the cold condition followed the lead car 22% (0.82 seconds) closer and applied the brakes 7% harder when presented with a stop sign during a following task. This behavior was predicted by subjective sensation and not by physiological response to cold. The current results suggest that drivers exposed to cold environmental conditions are more likely to display aggressive driving behavior.

The Impact of Cold Stress on Driving Performance

Exposure to cold environments can impact complex task performance due to increased error from cognitive and physiological stress. Few studies have examined the effects of cold stress on driving performance or the potential for advanced driver safety systems to detect error. The current study aims to examine the effects of cold stress by way of skin cooling on driving simulator performance, and evaluate vehicle behavior metrics for possible dangerous driving detection systems. Driving under cold stress is expected to result in systematic vehicle behavior and driving performance error, which can be utilized for future safety system research and development.