Have you repressed the memory of a traumatic experience from childhood? Is it now a leaking toxin, exerting a malevolent influence on you from your deep unconscious - explaining perhaps your attachment to alcohol or irrational mood swings? And, if so, what will it take for you to recover that memory and set yourself free?
According to a significant proportion of UK therapists, the chances that adult depression is linked to an episode of sexual abuse in childhood are relatively high. Estimates of the extent of childhood sexual abuse vary wildly from one in four to one in 100. But a substantial proportion of mental health professionals and other therapists signed up to the message in the late 80s and early 90s that 'just because you don't remember being abused, doesn't mean you weren't'.
Over the past 10 years, this theory has been challenged, not least by the British False Memory Society (BFMS) set up to represent the thousands of adults who say they've been falsely accused by children whose 'repressed' memories were 'recovered' in therapy.
A 1995 study of the British Psychological Society's 38,000 members found that four out of 10 of them use 'recovered memory work' in therapy. Following bitter internal disagreements, the Royal College of Psychiatrists failed to adopt as policy a 1997 report by Professor Sydney Brandon which dismissed 'recovered memory' as lacking evidence, denounced the 'unscientific' practices that were being widely used to achieve them, and warned that expectation of finding memories of sexual abuse in childhood, could be self-fulfilling.
Perhaps the single characteristic that identifies these 'extractions', is the length of time they take. The BPS reported that clients on average begin to have flashbacks after four months of therapy - with full recovery taking roughly 50 weeks. It can take longer.
Take the case of Linda Caine, co-author of the recently published Out of the Dark with her psychiatrist, Dr Robin Royston. The book documents the 'unravelling of the secrets of her childhood'.
'There's something she wants to tell us, but she can't get it out,' Dr Royston notes a year into therapy. A sinister, 'dark-haired man' starts to figure in Caine's dreams, six months later, however, the crucial memory refuses to materialise. 'Whenever I think about the worst thing that could have happened to me, I can't.' Linda tells Dr Royston, 18 months into therapy. He reassures her: 'Your mind will deliver when it's ready.'
When it does emerge, a full 32 months after the start of her therapy, the memory is indeed horrifying. The dark-haired man, a boyfriend of Linda's mother, not only raped the five-year-old child repeatedly but chillingly silenced her, terrifying her into repressing her memories.
'The evidence suggests that a high proportion of people who have been sexually abused as children will have no memory of that abuse,' says Dr Royston, 'though they may well have other problems with alcohol, sexuality and depression. And many will only recover those memories through therapy.'
But another book, due out in May, puts forward new evidence suggesting that if the phenomenon cannot be entirely ruled out, it can be shown to be highly unlikely. Remembering Trauma by Richard McNally, Professor of Psychology at Harvard University, describes innovative research into the phenomenon. Using 'behavioural, imaging and psychophysical methods', the research is the first to study people with various experiences of remembering sexual abuse in childhood, rather than playing word memory games with 'healthy' students, as most previous research has done.
'What we found,' he says, is that most people remember horrific experiences all too well. Victims of abuse are seldom incapable of remembering their trauma, in fact they're far less likely to forget traumatic than everyday events and if anything, would prefer to remember them less well,' he says.
Of course there are cases of people forgetting about unpleasant events. 'A common pattern is that something happens that you know was wrong. You don't mention it to your parents or friends because you don't want to worry them. Then you get on with your life and it seems to disappear from your memory.'
People do recover those memories, he says. Something happens - they see a TV programme that brings up the memory or a friend talks about a similar experience. 'What happens, though, is that they remember immediately. There's never any question of them remembering slowly bit by bit, or requiring therapy to help them remember.'
Equally significantly, Professor McNally's research has also shown up the ease with which memories can be created. A recent investigation of people who claim to have been kidnapped by aliens showed that many believe in these experiences 'so deeply that they display real stress symptoms similar to those of traumatised battlefield veterans'.
'This research underscores the power of emotional belief, particularly in vulnerable people who have a tendency to believe in fantasies,' McNally says. 'It's the beginning of an explanation of how people "recover" memories, and it's very worrying.'
Mark Pendergrast, author of Victims of Memory and a consultant to BFMS, estimates that 10 years ago, around 5,000 British therapists specialised in extracting abuse memories. 'I believe that such therapists urged clients to unearth what they thought were real incest memories. But the evidence continues to stack up that this type of therapy is flawed. It is startling that inspite of the numbers involved, there are no corroborated cases of massive repression in which people supposedly forgot years of traumatic events only to recall them much later in life. And the stories of people who recovered memories and subsequently retracted their allegations are chilling testimony to the harmful effects of this type of misguided therapy.'