Abstract
This chapter reviews key findings since 2014 that are relevant to estimating the relative crash risk of conversing via a cell phone during real-world and naturalistic driving in passenger vehicles. It updates chapter 102 in the previous edition of this Encyclopedia (Young, 2015a). The objective is to determine if recent data confirms the conclusion in Young (2015a) that engaging in a cell phone conversation does not increase crash risk beyond that of driving without engaging in a cell phone conversation. In particular, a recent estimate is presented of the relative crash risk for cell phone conversation in the Strategic Highway Research Program 2 (SHRP2) naturalistic driving study data. This estimate is compared with five other estimates in a meta-analysis, which shows that cell phone conversation reduces crash risk (i.e., has a protective effect). A recent experimental study will also be discussed, which supports the hypothesis that driver self-regulation gives rise to the protective effect by compensating for the slight delays in event response times during cell phone conversation.
TopIntroduction
A few brief definitions of basic terms will facilitate understanding the research updates reviewed in this chapter. This chapter uses the same definitions of terms as in the corresponding article in Chapter 102 in the previous edition of this Encyclopedia (Young, 2015a), except for the following additions and enhancements.
Key Terms in this Chapter
Driver Distraction: “The diversion of attention away from activities critical for safe driving toward a competing activity, which may result in insufficient or no attention to activities critical for safe driving” ( Regan et al., 2011 , p. 1776).
Cognitive Load: The loading of cognitive resources, “which are the alerting, executive, and orienting attentional networks singly or in combination, as well as the memory and representational systems (e.g., working and long-term) from which information may be retrieved and in which it may be held and operated upon” (Foley et al., 2013 AU23: The in-text citation "Foley et al., 2013" is not in the reference list. Please correct the citation, add the reference to the list, or delete the citation. ). Same as Cognitive demand (see Introduction).
Crash Risk: The probability of crash occurrence.
Compensation: As used here, a synonym for self-regulation. For example, during a cell phone conversation, drivers tend to compensate for the 200-300 millisecond increase in their brake response time by increasing their headway times to a lead vehicle.
Self-Regulation: A change in tactical driving behavior to compensate for adverse effects on safety from a secondary task. A synonym for compensation.
Cognitive Distraction: “Any epoch of cognitive loading that competes with activities necessary for safe driving” (Foley et al., 2013 AU22: The in-text citation "Foley et al., 2013" is not in the reference list. Please correct the citation, add the reference to the list, or delete the citation. ).
Driver Attention: Attention is three entities, not one as commonly believed. The alerting, executive, and orienting attentional networks in the brain are separate networks that can be affected in opposite ways by cell phone tasks. For example, Talk improves alerting attention, while slightly diminishing orienting attention.
Cell Phone Conversation: Talking/listening on a wireless device. Abbreviated in this chapter as Talk.
Talk RR: The relative risk of cell phone conversation while driving.