We've all been told off, quite rightly, for 'distracted driving' - but distracted walking?
But according to researchers at the University of Maryland School of Medicine, the number of serious injuries to pedestrians listening to headphones has more than tripled in six years.
In many cases, cars or trains are sounding horns that the pedestrians can't hear, leading to fatalities in nearly three-quarters of cases, they say.
"Everybody is aware of the risk of cell phones and texting in automobiles, but I see more and more teens distracted with the latest devices and headphones in their ears," says lead author Richard Lichenstein.
"Unfortunately, as we make more and more enticing devices, the risk of injury from distraction and blocking out other sounds increases."
The team examined case reports from 2004 to 2011 from the National Electronic Injury Surveillance System, the US Consumer Product Safety Commission, Google News Archives and Westlaw Campus Research databases, looking for reports of pedestrian injuries or fatalities from crashes involving trains or motor vehicles.
There were 116 accident cases between 2004 and 2011 in which injured pedestrians were documented as wearing headphones. Seventy percent of the pedestrians were killed. More than two-thirds of victims were male and under the age of 30.
More than half of the vehicles involved were trains, and 29 percent reported sounding some type of warning horn prior to the crash.
And the rise in accidents over the years closely corresponds to the rising popularity of music players with headphones, says the team.
They suggest two possible causes: distraction and sensory deprivation, with the train or car warning signal drowned out by the music player's sound.
Dr. Lichenstein says the study was initiated after reviewing a tragic pediatric death where a local teen died crossing railroad tracks. The teen was noted to be wearing headphones and did not avoid the oncoming train despite auditory alarms. Further review revealed other cases not only in Maryland but in other states too.
"As a pediatric emergency physician and someone interested in safety and prevention I saw this as an opportunity to - at a minimum - alert parents of teens and young adults of the potential risk of wearing headphones where moving vehicles are present," says Lichenstein .