Site Loader

On average, drivers are distracted 50% of the time while driving (Dingus et al., 2016). It is not
uncommon for a driver to arrive at a destination, and then wonder how he or she made it there.
This phenomenon, first termed highway hypnosis, was thought to occur when “the monotony of
the surroundings and the necessity to attend only to a very small part of the visual field might
induce some kind of hypnotic trance” (Williams, 1963 as cited in Wertheim, 1978, p. 111). This
phenomenon is now commonly understood as mind wandering. Mind wandering is defined as “a
shift of attention away from a primary task toward internal information” (Smallwood &
Schooler, 2006, p. 946).

Several recent studies have evaluated how mind wandering affects driving performance
(Bencich, Gamboz, Coluccia, & Brandimonte, 2014; He, Becic, Lee, & McCarley, 2011; Yanko
& Spalek, 2014). Of these studies, the primary mind wandering detection methods were either
self-caught or probe-caught. Using the self-caught method, participants are instructed to press a
response button as soon as they notice their mind wandering (He et al., 2011). Alternatively,
using the probe-caught method, participants are instructed to press a response button to indicate
whether their mind was wandering when they hear a probe tone (Bencich et al., 2014; Yanko &
Spalek, 2014). If, at this time, the participant’s mind was not wandering, they are instructed to
press an alternative button to indicate a state of alertness (or task-related thoughts).

We Will Write a Custom Essay Specifically
For You For Only $13.90/page!


order now

He et al. (2011) used the self-caught method and found that variability in velocity increased
when drivers were alert compared to mind wandering. They also found that lateral control (i.e.,

79

PROCEEDINGS of the Ninth International Driving Symposium on Human Factors in Driver Assessment, Training and Vehicle Design

steering, lane deviation, lateral position variability) was unaffected by the driver’s state of
internal attention. Similarly, when using the probe-caught method, Bencich et al. (2014) found
that speed and speed variability increased when drivers were alert compared to mind wandering.
Conversely, Yanko and Spalek (2014), who also used the probe-caught method, found that
participants drove at greater speeds when mind wandering compared to alert.

Given these inconsistent results, the purpose of the present investigation was to examine
performance differences when drivers were actively thinking about the driving task (here
referred to as an alert state) versus experiencing task-unrelated thoughts (here referred to as mind
wandering) using two common detection methods, self-caught and probe-caught. Although
researchers (e.g., Yanko & Spalek, 2014) suggest that both detection methods are equally
reliable, to our knowledge this has not been previously explored, at least in regard to driving.

One issue with the use of the self-caught method is that drivers’ must be aware of their mind
wandering in order to report it. Numerous studies, however, demonstrate that people are often
not aware, at least for much of the time, that they are mind wandering (for a review see Schooler
et al., 2011). Therefore, using a self-caught method may result in reduced reports of mind
wandering relative to the probe-caught method. Further, those self-caught instances of mind
wandering (when people have the meta-awareness of their mind wandering) may differ
systematically from probe-caught instances. Specifically, providing probes are likely to bring
drivers’ awareness back to the task at hand, interferring with the overall nature of the task.

Based on the observation that focusing attention on automatized tasks frequently decreases
performance (referred to as choking; see Ehrlenspiel, Wei, & Sternad, 2010; Koedijker & Mann,
2015), it was hypothesized, as assessed by operational control metrics, that driving performance
would be less variable while mind wandering than alert. Specifically, it was expected that speed
variability, lane deviation, lateral position variability and steering reversal rate would be lower
when mind wandering. This finding would support the results of previous studies evaluating
mind wandering while driving (Bencich et al., 2014; He et al., 2011). It was also hypothesized
that performance decrements elicited by mind wandering would not differ using the two
detection methods, but the frequency of reported mind wandering would be reduced in the Self-
Caught Experiment.

SELF-CAUGHT EXPERIMENT
Method

Participants. Twenty students (9 men, 11 women) from George Mason University participated in
the study for research credit. All participants were at least 18 years of age, held a valid driver’s
license, and had normal or corrected-to-normal vision and hearing. Visual acuity of at least 20/20
was verified using the Rosenbaum near vision test (Rosenbaum, 1984). On average, participants
were 19.95 (SD = 4.43) years of age and had 4.00 (SD = 4.09) years of driving experience.

Apparatus. Participants completed a series of questionnaires assessing mind wandering and
inattention, a demographics and driving history questionnaire, and the Karolinska Sleepiness

80

PROCEEDINGS of the Ninth International Driving Symposium on Human Factors in Driver Assessment, Training and Vehicle Design

Scale (KSS; A?kerstedt & Gillberg, 1990). The KSS was administered twice, once prior to the
experiment (along with the other questionnaires), and once after the experiment.

A medium fidelity driving simulator with a 240o rotation steering wheel, and pedals was used in
this study. The independent variables evaluated were attentional state (alert, mind wandering)
and drive (drive one, drive two). As is common in previous studies (He et al., 2011), periods of
mind wandering and alertness were evaluated via pairs of 10-second windows pre and post self-
caught button press. Here, mind wandering was defined as the period of -13 to -3 seconds prior
to the onset of the button press, while alertness was defined as the period of 3 to 13 seconds
following the button press (see Figure 1).

Figure 1. Self-caught mind wandering detection times

The dependent variables were average speed (km/h), speed variability (standard deviation of
speed), lane deviation (root-mean-squared-error in meters from lane center), lateral position
variability (standard deviation in meters of each participant’s mean lateral position), and steering
reversal rate (see He et al., 2011).

Procedure. Participants signed an informed consent form and completed a series of surveys.
Participants then completed a practice drive (7 minutes), drive one (15 minutes), the sustained
attention to response task (SART; Robertson, Manly, Andrade, Baddeley, & Yiend, 1997) for 15
minutes, drive two (15 minutes), and then the second KSS. During the practice drive, participants
were instructed to maintain a speed of 96.56 km/h (60 mph), stay in the right lane, and when
prompted, to exit the highway and proceed back onto the highway in the opposite direction.
Following the practice drive, participants were instructed to read a mind wandering definition
adapted from Singer and Antrobus (1972). The instructions for the two experimental drives were
similar to the practice drive with one exception. Participants were instructed to press a button on
the steering wheel when they noticed they were mind wandering (He et al., 2011; Smallwood &
Schooler, 2015). Between the experimental drives, participants completed the SART to induce
cognitive fatigue (Robertson et al., 1997). Performance data on the SART is not presented here. 

Post Author: admin

x

Hi!
I'm Rhonda!

Would you like to get a custom essay? How about receiving a customized one?

Check it out