Friday, July 24, 2009

Article from BBC about OCD brain activation

http://news.bbc.co.uk/2/hi/health/4900456.stm

Mistakes 'aid OCD understanding'
Everyone is familiar with the sinking feeling you get after deleting a computer file by mistake or leaving the house without your keys.

But such events also cause their own unique reactions in the brain.

US scientists writing in the Journal of Neuroscience found one area becomes more active after "costly" mistakes.

They say it may help explain obsessive compulsive disorder, where minor events appear to be enough to trigger an over-reaction in the same area.

An exaggerated perception of error is likely to be linked to the untoward anxiety about errors or failures
Dr Heather Sequeira, St George's Hospital,

In the study, the brains of 12 healthy adults were examined using a functional MRI (fMRI) scanner while they were undertook 360 computer tests, such as spotting the odd one out or picking pairs of letters.

Succeeding at some carried a small financial reward, while failing at others incurred penalties. Others carried no reward or penalty.

People were told they had a $10 (£5.70) "credit" to begin, and that they would receive real cash depending on their balance at the end.

The response to a mistake that cost them money was seen to be greater than the response to other mistakes and involved a part of the brain called the rostral anterior cingulate cortex (rACC).

That part of the brain did not show the same level of activity when the mistake did not carry a penalty, or had a neutral consequence.

The researchers had already found in previous research that the rACC area did become more active when there was no cost in people with OCD.

Therapy

OCD is often characterised by an untoward anxiety or fear about errors or failures in certain aspects of everyday life, with repetitive patterns of behaviour to ward off or prevent such events.

Stephan Taylor, who led the US research, said: "It's very interesting to us that the same part of the brain that responded in our OCD study on regular, no-cost errors also responded in healthy individuals when we made the error count more."

"It appears to us so far that OCD patients may have a hyperactive response to making errors, with increased worry and concern about having done something wrong," he says.

"We hope that this kind of research will help us get a handle on this condition and see which normal brain circuits have gone awry in people with OCD.

The next step is to study OCD patients using the same test as was used in healthy participants, and to see if "talking therapies" have any effect.

Stress link

Dr Heather Sequeira, a psychologist at St George's Hospital, London, said: "This is a very intriguing piece of research.

"In clinical practice we often find that OCD develops following a significant life event or increase in stress - particularly when it is associated with an increase in responsibility for the person, such as being promoted or having a baby.

"In a person who is susceptible to OCD, conceivably because of the rACC differences described by these researchers, these periods of increased stress may well be the very times when ' everyday mistakes' are perceived as carrying a greater penalty.

"An exaggerated perception of error is likely to be linked to the untoward anxiety about errors or failures and the associated compulsive checking, washing and other repetitive responses associated with OCD."

Thursday, July 16, 2009

Low B12 in 20% of OCD patients...

Though the title says most of it, below is the excerpt about the study, from diagnose-me.com article on OCD (full address http://www.diagnose-me.com/cond/C167910.html):

"In one study of OCD patients, 20% had abnormally low serum vitamin B12 concentrations compared to the two control groups. [Acta Psychiatr Scand 78(1): 8-10, 1988.]"

Tuesday, July 14, 2009

Inositol Reduces OCD symptoms

From lef.org article on OCD:

"In a trial that compared inositol supplementation to placebo, 13 patients with OCD took inositol or placebo for six weeks. Patients experienced a significant reduction in OCD symptoms while they were taking inositol compared with the weeks they were taking placebo (Levine J 1997)."

Reduced Melatonin levels in OCD

From lef.org article on OCD:

"An additional angle of interest involves the pineal hormone melatonin. Melatonin is well known to induce sleep in humans. At least one study has shown that people with OCD tend to have depressed melatonin levels, along with elevated levels of the stress hormone cortisol (Monteleone P et al 1995)."

Acute Tryptophan Depletion results in worsened symptoms...

From lef.org article on OCD:

"Another dimension to these findings was added by a double-blind, placebo-controlled study at McGill University in Montreal, in which researchers found that acute tryptophan depletion caused patients to experience significantly greater subjective distress when they were provoked with triggering situations (Berney A et al 2006)."

Folate Low, Homocysteine High in OCD

Résumé / Abstract

Previous studies have shown that folate deficiency, increased homocysteine, impaired metylation have been identified in depressive disorder. Recently, growing research has resulted in the biological association between obsessive-compulsive disorder (OCD) and affective disorders. Therefore, in the present study it was evaluated whether or not folate and homocysteine levels changed. Serum folate and homocysteine concentrations were measured in 23 patients with OCD and in same number of controls. In addition, all patients were assessed by Yale-Brown Obsession Compulsion Scale (Y-BOCS). Serum folate values were significantly lower in OCD patients than in controls, while homocysteine concentrations were higher in patients compared with controls. Serum folate values were significantly and negatively related to Y-BOCS scores. Total serum homocysteine concentrations were positively correlated to Y-BOCS scores and the duration of illness. There was a trend toward a negative correlation between the concentrations of serum folate and homocysteine. In conclusion, we identified that a group of patients with OCD might have folate deficiency, higher homocysteine levels and probable impaired metylation and monoamine metabolism.

Titre du document / Document title

Serum folate and homocysteine levels in patients with obsessive-compulsive disorder

Auteur(s) / Author(s)

ATMACA Murad (1) ; TEZCAN Ertan (1) ; KULOGLU Murat (1) ; KIRTAS Ozlem (1) ; USTUNDAG Bilal (2) ;

Affiliation(s) du ou des auteurs / Author(s) Affiliation(s)

(1) Firat University, School of Medicine, Department of Psychiatry, Elazig, TURQUIE
(2) Firat University, School of Medicine, Department of Clinical Biochemistry, Elazig, TURQUIE

Revue / Journal Title

Psychiatry and clinical neurosciences ISSN 1323-1316

Source / Source

2005, vol. 59, no5, pp. 616-620 [5 page(s) (article)] (28 ref.)

Langue / Language

Anglais

Editeur / Publisher

Blackwell Publishing, Carlton, AUSTRALIE (1995) (Revue)