Anaesthetic could be used to help people forget traumatic memories, scientists believe, after proving they could weaken the strength of recollections in human trials.

Researchers have known for some time that when people undergo anaesthesia during surgery, it can have implications for their memory.

They wanted to test whether administering a dose at a crucial period of memory formation could get rid of thoughts of stressful past events.

For the experiment, 50 volunteers were asked to watch two slide shows, both of which showed upsetting content.

A week later they returned and were reminded of the content of one of the second slideshow, before being given the anaesthetic propofol intravenously, which sedated them for an average of 12 minutes.

The results showed that those who had been asked to remember the second slideshow 24 hours later struggled to recall the details after the anaesthetic, but could still recall the first.

Stress-related disorders are often associated with the vivid remembering of traumatic experiences.

The researchers hope that it will be possible to develop a therapy which combines memory reactivation and anesthetic for disorders like post-traumatic stress disorder (PTSD).

They believe the therapy may work by preventing the firing of neurons which consolidates memories over time.