Mouse Model That Replicates Human OCD Can Point To More Effective Treatments

Jack Dikian

September 2011

Researchers at the University of Chicago are using a new model of obsessive-compulsive disorder (OCD) that mirrors both symptoms of the disease and the timing of its treatment in humans. In the paper published in Biological Psychiatry the researchers report that they have been able to use the model to isolated a single neurotransmitter receptor in a specific brain region responsible for their model's OCD-like symptoms, offering new insight into the cause of the disorder.

Having a model that seems to mimic the disorder so well, especially in terms of the time course of treatments that work in humans, is potentially very useful for researching novel therapeutics. It’s possible that with further research the model may point the way to new treatments for both OCD and autism.

With a model that replicates aspects of OCD, researchers can dig deeper into the specific neurotransmitters and systems involved in the disorder. A drug that is used to treat migraines, but also known to have the unintended effect of increasing anxiety and compulsions in people with OCD was shown to bring about highly repetitive patterns of locomotion in mice.

The drug-treated mice also exhibited deficits in prepulse inhibition, a form of startle plasticity thought to measure the brain's ability to filter out intrusive thoughts, which plague OCD patients. To determine whether these drug-induced behaviors reflected the neurobiology of OCD, the researchers tested the same drugs used to treat the disorder in humans. After four weeks of pre-treatment with SRIs - the same duration required to see therapeutic effects in humans - drug-induced OCD behaviors were reduced in the mice.

The researchers then looked for a specific brain region where activation of 1b serotonin receptors creates OCD-like symptoms. In humans, scientists have identified a region called the orbitofrontal cortex that is more active in OCD subjects. Again matching the human data, selectively activating 1b receptors in the orbitofrontal cortex with the drug was sufficient to produce the OCD-like symptoms in the mice.

The results offer promising ideas about developing new treatments for OCD. A drug that blocks the serotonin 1b receptors may be effective in reducing OCD symptoms; however, no such chemical is currently available according to the researchers.

Researchers

Stephanie Dulawa, PhD, assistant professor in the Department of Psychiatry and Behavioral Neuroscience at the University of Chicago Medical Center and senior author of the study

Nancy Shanahan, PhD, lead author of the paper in Biological Psychiatry

Yawning may cool the brain

Jack Dikian

September 2011

Yawning may be more than a marker for boredom or fatigue; it may be a way of cooling the brain. A study by researchers at Princeton University and the University of Arizona report in the journal Frontiers in Evolutionary Neuroscience that yawning frequency varies with the season. People are less likely to yawn when the heat outdoors exceeds body temperature - indicating that yawning could serve as a method for regulating brain temperature.

They found that participants in the study were more likely to yawn in the winter, as opposed to the summer when ambient temperatures were equal to or exceeding body temperature. The researchers concluded that warmer temperatures provide no relief for overheated brains, which, according to the thermoregulatory theory of yawning, stay cool via a heat exchange with the air drawn in during a yawn.

Third Sex

Jack Dikian

September 2011

Sex and Gender Diverse Passport Applicants

Perusing the revised policy on Sex and Gender Diverse Passport for applicants on the Australian Government Department of Foreign Affairs and Trade, I see it is now possible for a passport to be issued to sex and gender diverse applicants in M (male), F (female) or X (indeterminate/unspecified/intersex). To be perfectly honest, I’m not really sure how new this is. I came by it quite by chance.

We know that biology determines genetically whether a human being is male or female (on the basis of the XX or XY or a variation thereof chromosomes), the state of being neither a man or a woman is sometimes considered in relation to the individual's gender role in society, gender identity, sexual orientation or any other characteristic.

The passport office website informs that a medical practitioner certifies that the person has had, or is receiving, appropriate clinical treatment for gender transition to a new gender, or that they are intersex and do not identify with the sex assigned to them at birth. Of course, applicants must meet all other normal passport requirements, such as providing proof of identity documents to support their identity in the wider community.

Eternal love and marital happiness

Jack Dikian

September 2011

Family therapists began to look at new ways of understanding and explaining human behavior - proposing that psychological problems were developed and maintained in the social context of the family.

This shifted the contextual perspective, relocating the responsibility for the problems and the focus of treatment from the internal world of the individual patient to the entire family. Family therapy is today not only a household term, but a popular and effective intervention.

There is in nature a strange delicate flower that in some cultures, such as to the Japanese, symbolises eternal love and marital happiness - The Venus flower basket.

This is a creature that only grows on the deep ocean floor in the warm tropical waters and seldom seen. This extremely beautiful, intricate, and dainty has the shape of a tube and made of an intricate fine lace expertly spun in glass fibers no thicker than human hair. The smaller, tapered end is anchored to the ocean floor by a multitude of fine glass-like fibers. The larger end has a lacey looking cap over it.

When the Venus flower basket is small, tiny shrimp swim in and out of it. However, as the Venus Flower Basket grows it seals off the open upper end, and at the same time the shrimps grow so that they cannot swim through the side of the Venus flower basket. As this happens, a pair of shrimps, one male and one female, will stay inside the Venus flower basket and become trapped there. This pair of shrimps will spend the rest of their lives inside that Venus flower basket x.

A deep male voice helps women remember

Jack Dikian

September 2011

Barry White made women all over the world swoon when he sang….And now research proves that men with deeper voices are actually more appealing to women.

According to a new study by David Smith and colleagues from the University of Aberdeen in the UK, published online in Springer's journal, Memory & Cognition, a man’s low masculine voice is important for both mate choice and the accuracy of women's ability to remember. The study indicates that if you want women to remember, speak to them in a low pitch voice. Depending on what they remember about you, they may or may not rate you as a potential mate.

In a series of two experiments, Smith and colleagues show that memory in women is sensitive to male voice pitch, a cue important for mate choice because it can indicate genetic quality as well as signal behavioural traits undesirable in a long-term partner. These could include antisocial traits and lack of emotional warmth for example. In order to evaluate potential partners, women appear to rely on their memories to rapidly provide information about the attributes and past behaviour of potential partners.

Smith concludes: "Our findings demonstrate that women's memory is enhanced with lower pitch male voices, compared with the less attractive raised pitch male voices. Our two experiments indicate for the first time that signals from the opposite-sex that are important for mate choice also affect the accuracy of women's memory."

This may be a significant factor in mate choice because it can hint at testosterone levels and genetic quality, evolutionary psychologists suggest. “Lower-pitched men’s voices are not only rated as more attractive, but are associated with a greater number of reported sexual partners, and greater reproductive success than are higher-pitched men’s voices,”.

Dr. Kevin Allan, who supervised the research, said, "We think this is evidence that evolution has shaped women's ability to remember information associated with desirable men. Good memory for specific encounters with desirable men allows women to compare and evaluate men according to how they might behave in different relationship contexts, for example a long-term committed relationship versus a short-term uncommitted relationship. This would help women to pick a suitable partner, and that's a particularly important ability to have because the costs of poor mate-choice decisions can be severe."

Reference

Smith D et al (2011). A modulatory effect of male voice pitch on long-term memory in women: evidence of adaptation for mate choice? Memory & Cognition. DOI 10.1007/s13421-011-0136-6

The location of meaning

Jack Dikian

September 2011

Lately my work as a practitioner, and a clinical supervisor, has prompted me to think a lot about meaning, and more so the location of meaning. I’m aware the premises of a phenomenological psychology is one that focuses on meaning, or, more precisely, on the human preoccupation with meaning, and that for a long time has been, by in large an academic concept. But re-reading Gödel, Escher, Bach: An Eternal Golden Braid by Douglas Hofstadter, I’m appreciating a subject-matter that I perhaps overlooked many years ago.

Another part to this is the influence Paul Davies’ book, The Eerie Silence, and the search for Alien Intelligence. Not so much whether we are alone, or there are other beings out there in the vast universe, but more, how might Aliens’ find meaning in our broadcasts even if they were to intercept them.

Hofstadter examines whether meaning can be said to be inherent in a message, or whether meaning is always manufactured by the interaction of a mind or a mechanism with a message. He invites the reader to consider a thin plastic platter with a hole in the middle (we know this to be an old fashioned record containing music) is hurled into deep space. It has lost all context, music, record-player, etc. How much meaning does it carry? If an alien civilization were to encounter it, they would almost certainly be struck by its shape, and would probably be very interested in it. Thus immediately its shape, acting as a trigger, has given them some information: that it is an artifact, perhaps an information-bearing artifact.

We can imagine that if such a record had arrived on Earth in Bach's time (1600’s and 1700’s), no one would have known what to make of it, and very likely it would not have gotten deciphered. If we imagine for a minute that we are bathed by a sea of radio messages from other civilizations, messages which we do not yet know how to decipher – a deep problem is the question, "How will we recognize the fact that there is a message at all? How to identify a frame?"

In these examples of decipherment of out-of-context messages, we can separate out fairly clearly three levels of information: (1) the frame message; (2) the outer message; (3) the inner message. The one we are most familiar with is the inner message. It is, after all, the message which is supposed to be transmitted: the emotional experiences in music, the phenotype in genetics, the royalty and rites of ancient civilizations in tablets, etc. To understand the inner message is to have extracted the meaning intended by the sender. The frame message is the message "I am a message; decode me if you can!".

The three levels are very clear in the case of a message found in a bottle washed up on a beach. The first level, the frame message, is found when one picks up the bottle and sees that it is sealed, and contains a dry piece of paper. Even without seeing writing, one recognizes this type of artifact as an information-bearer. Next, one opens the bottle and examines the marks on the paper. Perhaps, they are in Japanese; this can be discovered without any of the inner message being understood. It merely comes from a recognition of the characters.

It is in the nature of outer messages that they are not conveyed in any explicit language. It is always the listener's burden to understand the outer message and the success of that lets him break through into the inside, at which point the ratio of triggers to explicit meanings shifts drastically towards the latter. This is a bit like recognizing in a sea of radio signals that a particular signal is a frame – a bottle carrying an inner message.

Autism, siblings and gender

Jack Dikian

September 2011

According to the latest Medical News Today, which uses sources including JAMA, BMJ, Lancet, and BMA reported that parents of a child with autism face a risk of almost one in five that their next child will also develop the disorder.

The risk is higher than previous estimates, and goes even higher if the second child is a boy. In fact, the risk rises to over 26% if the second child is male, and over 32% for infants with more than one older sibling with autism.

The Centre for Autism & developmental Disabilities Epidemiology (CADDE) at Johns Hopkins Bloomberg School of Public Health report, amongst other things, that there are 4 boys for every 1 girl with autistic disorder.

Scientists are working hard to narrow down the regions on chromosomes 7 and 15 to identify the specific gene(s) related to autism on these chromosomes. They are also expanding their searches to investigate other chromosomes for which there is preliminary suggestive evidence.

A report commissioned by Autism Advisory Board on Autism Spectrum Disorders notes that while there is considerable degree of variation in prevalence figures depending on the sources of data, using the Commonwealth Government’s Centrelink data, the core finding estimates the prevalence of autism spectrum disorders across Australia of 62.5 per 10,000 for 6-12 year old children. This means there is one child with an ASD on average in every 160 children in this age group which represents 10,625 children aged between 6 and 12 years with an ASD in Australia.

A similar study just released in the United States by the Centre for Disease Control and Prevention1, found a similar, although slightly higher prevalence of 1 in 150 [66.5 per 10,000] children among eight year olds. Researchers noted that this was consistent with previously published studies.