The effects of conversing on the phone while driving are not simple, static,
or uniform. This is true for different driving conditions, different phone
tasks, different driving tasks, and different people. Despite the complexity
of the results, the following general conclusions can be made regarding the
driving conditions and tasks examined in this study:
- There is a learning process
that occurs for both the driving task and the distraction task. Over the
course of five sessions there was an improvement in the performance of most
of the driving measures and on the math distraction task. In parallel, the
subjectively evaluated workload decreased in a fairly monotonic manner.
in general, is poorest for the older drivers, and better for the two younger
groups of drivers, which generally do not differ from each other.
on the driving task is significantly affected by the required speed, being
generally poorer when required to drive at 65 mph than when required to drive
at 50 mph or follow another vehicle (also at speeds less than 65 mph).
the two phone distracting tasks used, the math operation is a much more difficult
task, as reflected in the poorer performance on the driving measures.
- An emotionally-involving
conversation is much less disruptive to driving than a math operation, and
in the case of many driving measures, it appears to be non-disruptive at
all (relative to the no distraction condition).
- The significant interaction
of the above conditions shows that the effects of the distracting task on
driving are greatest when the distracting task is difficult (math operations),
the driving demands are high (65 mph), the driver has no experience in performing
the dual tasks (Day 1), and the drivers are older (60-71 years old).
in accordance with the main hypothesis of this study, where learning is
observed, practice diminishes or completely eliminates the differences in
the performance on the driving task, between the no-distraction condition
and the two phone distraction conditions.