New Research Idicates How OCD Behaviours Are Formed

New Research Idicates How OCD Behaviours Are Formed

Obsessive compulsive disorder (OCD) is a debilitating condition affecting millions everyday. It is estimated that, in the UK, 2% of people aged between 18 and 56 suffer from some form of obsessive compulsive behaviour. Despite this widespread occurrence, however, there is much we do not know about the condition.

Historically, OCD has been dismissed as having no physiological cause, but scientists have shown that there are underlying biological factors in the condition. Functional magnetic resonance imaging studies have shown that the ventromedial prefrontal cortex, normally responsible for goal-based decisions, is implicated in the condition. Neurologists have also suggested several other areas play a role.

But how these physiological deficits manifest themselves is only just beginning to be understood. A recent study carried out in the Department of Experimental Psychology at Cambridge University indicates that the compulsions are due to overactive habit forming mechanisms.

Clair Gillan, a lead researcher in the study, said: ‘The goal was to look at the habit hypothesis of OCD, to see if [sufferers] had a greater predisposition to habit formation than control subjects’. The researchers were able to analyse this by comparing the abilities of control and OCD participants. Each subject was trained to use a computer programme to gain points by clicking on the correct boxes of fruit that appeared on screen. The fruits that gained the participants points were then changed. The OCD patients showed they were significantly less able than the controls to change the habit they had learned. They did not achieve their goals as successfully and thus gained fewer points. One participant, ‘Mr J’ (a severe OCD sufferer), commented that when he saw the fruits it was as if his ‘hands knew what to do’ and followed the earlier training goals, not the newer goals.

There are several different techniques currently used to treat OCD. These include the drastic (such as surgery), the experimental (such as psychedelic drugs) and the psychological (such as behavioural therapy). ‘I think it’s a very important validation of cognitive behavioural therapy’ said Gillan commenting on her study. She highlighted in particular the ‘exposure and response prevention technique’, also known as Pavlovian extinction. Patients undergoing this therapy are exposed to their feared situation.

Whilst our knowledge of OCD has no doubt improved, there is still much to discover.

ResearchBlogging.org
Gillan CM, Papmeyer M, Morein-Zamir S, Sahakian BJ, Fineberg NA, Robbins TW, & de Wit S (2011). Disruption in the Balance Between Goal-Directed Behavior and Habit Learning in Obsessive-Compulsive Disorder. The American journal of psychiatry PMID: 21572165

Science Hoax of the Week – The Nipple Transplant Slimming Technique

Science Hoax of the Week – The Nipple Transplant Slimming Technique

This was originally printed in Felix however, has been expanded on here.

The ficticious Dr. Jonas Zizlesse, M.D., P.A., F.A.C.S.

“Why would you want to diet? It’s hard! You can’t eat what you want when you want!” It’s an appealing case made by the website of Dr Zizlesse. However, this hoax website (viewable here) gives a rather unappealing alternative to dieting, nipple transplants. The theory is that by transplanting nipples onto rolls of fat you tap into societies fixation with breasts, turning the obese into multi-mammary jordan-esque glamour models. It declares in their emails that “FAT IS ONLY UGLY UNTIL YOU PUT A NIPPLE ON IT!”.

Thankfully Dr Zizlesse and the ‘Nipple Addition Surgery’ are completely fabricated having been made up by persistent internet satirist and prankster Hyperdiscordia.

Here are a few before and after shots from the “treatment”

Before

After

New Gene Therapy Idea Brings Hope of Possible New HIV Treatment

A new study aimed to aid the progression of HIV/AIDS gene therapy published in Nature Biotechnology has shown promising results. The study involved the genetic disruption of the CCR5 gene in mice, following this the mice were observed to have normal T cell counts and there were no further medical complications.

Researchers have known about the presence of the HIV ‘aiding’ gene CCR5 for many years. The CCR-5 gene encodes for a receptor protein of the same name found in a variety of immune cells which is thought to play a role in the inflammatory response to infection. In HIV-1 the virus binds to the CCR-5 receptor protein, facilitating the infection of the immune cell, enabling the spread of the disease. There is a naturally occurring null allele for CCR-5 protein which 1% of the Caucasian population are homozygous for. These individuals express resistance to the HIV-1 strain.

The study carried out at the University of South California, used genetically altered human stem cells for injection into mice.  One group of mice was injected with CCR-5 disrupted stem cells whilst the others were given wild type stem cells. Following infection with HIV the control mice showed vast disruption of the immune system due to infection. However, the CCR-/- mice showed ‘significantly’ lower HIV levels and the human stem cells were found throughout the tissues of the body.

This is not the first time the CCR-5 receptor has been therapeutically targeted, pharmaceutical companies have been developing drugs to interrupt the interaction between viral HIV and CCR-5 for many years with varying success. Maraviroc (made by Pfizer) has recently been approved for treatment, whilst Alpaviroc (made by GSK) failed its clinical trials and Vicriviroc (made by Schering-Plough) is still being tested.

Whilst CCR-5 remains a good target for therapeutic intervention it is not likely to bring about a cure. The second main HIV strain, HIV-2, targets a different receptor CXCR-4, for which there has been no naturally occurring null allele yet found in the general population. The use of similar targeting techniques using a CXCR-4 knock out stem cell line could be promising for treatment of this strain. However, the fast mutation rate of both the HIV virus strains means that means that the window of no resistance may be limited.

In such a complex and challenging disease it is common that the slightest new discovery be heralded as the key scientific breakthrough. However, this new treatment does shown genuine promise and whilst not the vaccine or cure that is so desperately sought after it could prove to be a valuable weapon in humanities arsenal against the AIDs epidemic.

Ben Good

Study: http://www.nature.com/nbt/journal/vaop/ncurrent/abs/nbt.1663.html