It seemed like wild science fiction when characters in the 1997 film Men In Black erased people's memories with a device called a "neuralyzer". But a breakthrough by Israeli scientists means that memory erasing could become a reality.

The difference is that while Men In Black agents had dubious objectives, Hebrew University researchers are finding ways of erasing specific memories in order to free drug users from their addiction.

Rami Yaka of the university's Institute of Drug Research got a pack of rats hooked on cocaine over a two-week period, and then managed to wipe their memories of their high, meaning that they no longer hankered after the drug.

The rats lived in a cage that contained one chamber with a supply of saline solution and another with a supply of cocaine. During the fortnight that Dr Yaka spent offering the drugs, they were drawn to the cocaine chamber. He then gave half of the druggie rats a peptide - a compound of amino acids - called ZIP. He injected it directly into a part of the brain that controls pleasure and reward.

The injected rats were no longer drawn to the chamber of the cage where cocaine had been, while the non-injected rats were.

"This concept could save lives," said Dr Yaka, explaining that currently 90 per cent of recovered drug addicts relapse within a year, and a relapse for somebody on hard drugs can prove fatal.

Craving for a drug actually increases, instead of easing off, over time, and is triggered by various "cues" - visual, emotional, or even smells and sounds.

Dr Yaka says that his injection inhibits the growth of proteins which feed cravings.

He believes that it will eventually be usable in humans to treat a range of addictions, including drugs, alcohol, gambling, sex and obsessive eating. "It's just a matter of time before we can test it on different behavioural models," he said.