In the future, we might be able to choose our memories and delete the bad ones. Now that might sound like something from science fiction, indeed it’s the plot to films like Eternal Sunshine of the Spotless Mind, but could it actually happen?

Researchers at Columbia University have been using snails to try and single out memories in their brains and block the routes used to access them, essentially deleting or clocking certain memories. They say in the future the research could be used to treat human patients who suffer from PTSD or anxiety.