Motorists are being warned about the dangers of talking on the phone while driving after a study revealed mobile users meander more while walking and are less aware of their surroundings.
A total of 317 people were observed crossing a university campus square by America's Western Washington University researchers. Some in the study were talking on phones, listening to music and walking in pairs.
Another 151 others were watched walking across the square after the team asked a clown dressed in bright purple and yellow, large shoes and a shiny red nose to ride a unicycle nearby.
Those using mobile phones "made more direction changes, displayed more weaving, and were less likely to explicitly acknowledge other people", the research, led by Professor Ira Hyman, revealed.
Only 25% of mobile phones users said they saw the clown, compared with 71% of those in pairs, 61% of people listening to music and 51% of those alone.
Prof Hyman said mobile phone users were less likely to acknowledge others, illustrating "inattentional blindness".
"Unfortunately, when driving a car while talking on a cell phone, people may be unaware of what they are missing until it is too late," he added.
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