8:06am UK, Friday April 22, 2005

Workers' IQs are damaged more by the bombardment of emails, texts and phone calls than they would be by marijuana, says a report.

The constant interruptions from electronic communications were said to reduce productivity and leave people tired and lethargic.

Are emails worse than drugs?

Trying to respond to all these messages and carry out normal work took its toll on workers.

In 80 clinical trials, psychiatrist Dr Glenn Wilson, from King's College London University, monitored the IQ of workers throughout the day.

He found the IQ of those who tried to juggle messages and work fell by 10 points - the equivalent to missing a whole night's sleep.

This is considerably more than the four point fall detected after smoking marijuana.

Dr Wilson said: "This is a very real and widespread phenomenon.

"We have found that this obsession with looking at messages, if unchecked, will damage a worker's performance by reducing their mental sharpness."

David Smith, from Hewlett Packard which commissioned the research, said: "The research suggests that we are in danger of being caught up in a 24-hour 'always on' society."