Comments on: Perceptual distortions are common in population

By: michael

michael — Thu, 27 Oct 2005 15:57:14 +0000

Then is correct than bush was talking with God, because he is insane, otherwise it could be electric signal interpret by our mind
http://www.freepatentsonline.com/6011991.pdf

By: Vaughan

Vaughan — Wed, 26 Oct 2005 21:33:13 +0000

Hi Christian,
This sounds like a fantastic paper and one that addresses exactly the problem I mentioned earlier. I was totally unaware of it, so I’ll look forward to reading it as anything that tells us more about how unusual experiences become distressing is very valuable.
Thanks for the pointer!
Vaughan

By: christian

christian — Wed, 26 Oct 2005 21:11:36 +0000

Hi Vaughan
I don’t mean to be an all out apologist for the work of John Read and others, but one of their new papers (that I report on in a forthcoming issue of the BPS Research Digest) is a prospective study in the general population and does investigate the link between psychotic experiences and a history of trauma in people who have not visited a psychiatrist. Of thousands of people interviewed three years earlier, those who went on to develop psychotic symptoms were more likely to find them distressing if they had been traumatised as a child. That’s not to say the study is without problems! The paper I’m referring to is Bak, M. et al. (2005). Early trauma may increase the risk for psychotic experiences by impacting on emotional response and perception of control. Acta Psychiatrica Scandinavica, 112, 360-366.

By: Vaughan

Vaughan — Wed, 26 Oct 2005 18:04:50 +0000

John Read and others’ work, although highlighting the important role of childhood trauma in psychosis, often doesn’t directly address whether this contributes to perceptual distortions or perceptual distortions that become distressing and / or impairing.
This work, like much other work on psychosis, looks at the history or features of patients diagnosed with psychosis. To be diagnosed, patients have at some point turned up in front of a psychiatrist, usually because either they’ve become distressed or other people are worried about them.
This is a sample bias, in that it ignores all the people who may have very unusual experiences, perhaps that would otherwise be diagnosed as psychotic, were it not for the fact that they never get distressed and impaired by them.
In other words, there may be people who suffer childhood trauma, who also have intense perceptual distortions as adults, but remain functional and outside the mental health system as a result. Very little research has been done on this population, so it is very hard to say whether childhood trauma uniquely contributes to the disabling aspect of these experiences or just the presence of the experiences themselves.
My ex-colleague from Cardiff, Liz Andrews, was working with clairvoyants, mediums and other people who experienced voices, visions and so on. These people were generally not distressed or impaired by their experiences. Interestingly, Liz found higher levels of childhood trauma also in this population, suggesting trauma may not specifically be linked to adult disability and diagnosis, only to unusual experiences.

By: christian

christian — Wed, 26 Oct 2005 12:19:38 +0000

Regarding this bit: “It is not clear, however, why some people with high levels of unusual experiences become distressed and impaired by their experiences, often leading to a diagnosis of mental illness, while others are able to function and remain untroubled by them”, the papers published in the latest issue of Acta Psychiatrica Scandinavica (the subject of a previous post) argue that it is a previous traumatic experience(s), especially in childhood, that renders people vulnerable to finding such unusual sensory/perceptual experiences distressing, and thus likely to lead to illness. Look out for a forthcoming report on one of these studies at the BPS Research Digest (http://bps-research-digest.blogspot.com/).