New York, June 1 (PTI): Everyone knows that talking on a cellphone while driving is not safe. Now, a study establishes biologically the interference which takes place while carrying out the two tasks simultaneously.

A team at South Carolina University, led by an Indian origin researcher Amit Almor, has found that planning to speak and talking put far more demands on the brain’s resources than mere listening.

Their findings are based on two experiments which involved nearly 50 people. One required participants to detect visual shapes on a monitor and the other needed them to use a computer mouse to track a fast-moving target on screen.

In both the experiments, the participants performed the visual tasks while listening to narratives and responding to the narratives.

“We measured their attention level and found that subjects were four times more distracted while preparing to speak or speaking than when they were listening,” Almor said.