"Good" drivers turn bad when faced with poor driver etiquette, according to QUT research which has found many motorists are creating the problem they hate by responding aggressively to rudeness on the roads.
Lauren Shaw, from QUT's Centre for Accident Research & Road Safety - Queensland (CARRS-Q), said there was a widespread belief among drivers that their own on-road performance was good, and they expected other people's driving behaviour to be poor.
"It becomes a self-fulfilling prophecy when drivers respond aggressively to behaviour they think is bad," she said.
"My studies found common on-road events that trigger driver aggression from 'good' drivers were actions like poor merging, cutting off behaviours and tailgating.
"Although these behaviours are all dangerous, the reason they aroused anger was because the receiving driver thought it to be rude, inconsiderate and disrespectful. The offending driver had violated appropriate driver etiquette."
Ms Shaw said typical responses from 'good' but angered drivers, were to sound their horn, flash their lights or verbally vent their frustration.
She said the underlying motivation for these behaviours was to let drivers know they had behaved poorly, so that they would not repeat the behaviour in future.
"It's a contradiction. Good drivers are using rude and unpleasant bad behaviour to teach other drivers how to be better drivers," she said.
"All this does to the driver on the receiving end of the aggressive act is reinforce their own belief that the behaviour of other drivers is bad."
Ms Shaw said other research had also shown that expecting something to happen raises the likelihood that it will happen.
"In this context, drivers become more alert to instances of bad driver behaviour that meet this expectation," she said.
She said almost 40 per cent of drivers surveyed reported verbally venting their frustrations through actions such as name calling and while this might seem physically harmless, research had shown yelling increased driver danger.
"When drivers scream and shout they don't let the negativity go and it actually increases negative emotions and that increases crash risk," Ms Shaw said.
Ms Shaw said the good news was not all drivers reacted aggressively to poor etiquette.
"There are definitely those drivers who feel a level of superiority and perceive themselves as better than the offending motorists, and therefore refuse to respond aggressively," she said.
"These drivers feel that an aggressive response would be lowering their driving standards to that of the bad driver."
Ms Shaw's study focused on looking at the thought processes that promote driver aggression rather than the personality traits that make drivers behave aggressively.
"Driver aggression cannot be blamed on gender or age, it is widespread and linked to how we think about others' behaviours on the road," she said.
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