The research said people suffering from the emotional after-effects of traumatic experiences such as terrorist attacks or natural disasters could benefit from such a treatment.
A fearful memory was created by a team of Dutch researchers who associated pictures of spiders with a mild electric shock delivered to the wrists of 60 participants.
A day later the volunteers were shown the spider pictures and had their 'startle' response - a measure of fear - assessed by testing their eyeblink reactions.
The researchers saw a marked reduction in the startle response among those who had been given the beta-blocker drug propranolol before reactivation of the fearful memory, meaning they were much less disturbed by the spider pictures than those not given the drug.
Professor Merel Kindt and colleagues from the University of Amsterdam wrote in the journal Nature Neuroscience: 'Our findings may have important implications for the understanding and treatment of persistent and self-perpetuating memories in individuals suffering from emotional disorders.'
But British expert Dr Daniel Sokol, lecturer in Medical Ethics at St George's, University of London, has questioned the ethics of meddling with a person's mind in this way.
'It may perhaps be beneficial in some cases, but before eradicating memories, we must reflect on the knock-on effects that this will have on individuals, society and our sense of humanity,' he said.
Nature Neuroscience, 15 Feb 2009
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