The researchers observered whether passers by were talking on a cell phone, listening to an MP3 player, walking in a pair or walking without any electronic devices. In the first study, they noted that cell phone users walked slowly, frequently changed direction and were less likely to acknowledge other people than the participants without cell phones.

In the second study, researchers arranged for a clown on a unicycle to pass by the participants. Only 25% of the cell phone users noticed this bizarre occurence, compared to over 50% of the non-cell phone users.

The fact that cell phone users had difficulty walking is particularly alarming because walking is not a particularly demanding activity, whereas tasks like driving have high cognitive demands. This explains why talking on a cell phone while driving is one of the leading causes of road accidents in the UK.

"If people experience so much difficulty performing the task of walking when on a cell phonejust think of what this means when put into the context of driving safety. People should not drive while talking on a cell phone.", said Dr Ira E. Hyman, Jnr., head researcher of the study.