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What ‘Bad Dogs’ Can Teach Humans About Compulsive Behavior

Casey was diagnosed with canine compulsive disorder. He’s now on Prozac. (Courtesy)

Casey was diagnosed with canine compulsive disorder. He’s now on Prozac. (Courtesy)

When Casey, a 6-year-old German Shepherd, gets anxious, she chases her tail.

But it’s not the kind of endearing, once-around-and-it’s-done kind of tail-chasing we’ve all seen. Left unchecked, Casey circles around and around, pursuing her tail until she can bite it. Then, even when the blood starts flowing, the dog is driven to continue the chase.

“It’s upsetting,” says Paula Bagge, a Hopkinton, Mass. business owner who has been living with Casey since puppyhood. “And it’s damaging. She hurls herself around the house, and it’s like a big bloody paintbrush spraying the walls.” Once, Bagge tied the dog’s leash to a coffee table in an attempt to control the chasing. But Casey, who weighs about 85 pounds, just started dragging the coffee table around with her. Now, she’s on Prozac.

Dogs, it turns out, can have obsessive-compulsive disorder, just like people. And in a new study, Dr. Nicholas Dodman, a professor of clinical sciences at the Cummings School of Veterinary Medicine at Tufts University, found that structural brain abnormalities in dogs, in this case Doberman pinschers, with canine compulsive disorder (CCD) are similar to those of humans with OCD.

In an earlier study, Dodman, a leading researcher on repetitive behavior in animals, found a specific gene associated with canine OCD.

Studying anxiety disorders in dogs, Dodman says, may ultimately help scientists come up with better therapies and medications to treat OCD and related conditions in people. Current drugs for OCD, such as SSRI’s (or for dogs, a beef-flavored form of Prozac) are notoriously ineffective for many sufferers. Indeed, Dodman says, only around 43 to 60 percent of people suffering from OCD show a postive response from an SSRI; the average reduction of symptoms in people taking these drugs is only about 23 to 43 percent. “Certainly not a panacea,” he says.

So, to further this research, Dodman spends time thinking about bears who pace obsessively, for instance, or parrots unable to stop preening and picking their feathers and beagles who overeat to the point of exploding,

Dodman calls the latest dog-brain imaging study, conducted in collaboration with researchers at McLean Hospital, in Belmont, Mass., “another piece of the puzzle, another brick in the wall.”

He says while more research must be done, it’s becoming increasingly evident that dogs with OCD are a great model for exploring human psychopathology: they show similar behaviors, respond to drugs in comparable ways and now, at least in this small study, seem to have the same brain abnormalities as people with the condition. “When you know what your dealing with it’s much easier to create targeted approaches,” to treatment, Dodman says. “If you don’t know what you’re dealing with it’s just kind of like going with your sense of smell.”

OCD afflicts about 2 percent of the population and often goes untreated or undiagnosed. People suffering from the disorder, marked by intrusive thoughts and repetitive behaviors such as hand washing, locking and unlocking doors, counting, or repeating the same steps, feel these impulses as uncontrollable. And the compulsive rituals, often triggered by stress or trauma, can be incredibly time-consuming, interfering with daily life.

Famously, Lena Dunham, the star and creator of the HBO series “Girls” came out with her own OCD on air, with repetitive tics, obsessive counting and painfully compulsive use of Q-tips. Continue reading

Studies Show How Physical, Emotional Neglect Harms Children’s Brains

It’s not surprising but it is alarming: physical and emotional neglect has a harmful effect on children’s developing brains, new research shows.

(Southworth Sailor/flickr)

Children’s Hospital Boston’s blog Vector pulls together several studies that detail the various levels of damage that can be done to children’s brains when they are subject to trauma, neglect and social isolation:

Sheridan, Nelson and colleagues obtained brain MRIs from three groups of 8- to 11-year old children: 29 had been reared in an institution, 25 had left the institution for a high-quality foster home (where they spent 6 to 9 years), and 20 typically developing children who were never institutionalized served as controls.

The findings were mixed:

–Children who had spent their entire lives in an institution had significantly lower volumes of white matter—necessary for making connections in the brain—in the cortex of the brain than did the controls. But if they were transferred into foster care, their white matter volume became indistinguishable from that in controls. Continue reading

Study: Brain Differences Detectable In Autistic Children At Six Months Old

A new study suggests that differences in the brains of children at-risk of developing autism are detectable as early as six months of age.

Here’s some of the news release from Autism Speaks, one of the groups that funded the research:

The changes in brain development that underlie autism spectrum disorder (ASD) may be detectable in children as young as 6 months, according to research reported online today in the American Journal of Psychiatry. While core behaviors associated with ASD (impaired social communication and repetitive behaviors) tend to be identified after a baby’s first birthday, researchers found clear differences in brain communication pathways as early as 6 months in infants who later received a definitive diagnosis of ASD.

As part of the Infant Brain Imaging Study (IBIS), senior author Joe Piven, M.D., director of the University of North Carolina’s Carolina Institute for Developmental Disabilities in Chapel Hill, and his colleagues studied early brain and behavior development in 92 infants. These infants had older siblings on the autism spectrum and, so, were at elevated risk of developing ASD themselves.

“These results offer promise that we may one day be able to identify infants at risk for autism before the behavioral symptoms are present,” says study co-author Geri Dawson, Ph.D., Autism Speaks chief science officer. “The goal,” she adds, “is to intervene as early as possible to prevent or reduce the onset of disabling symptoms.” One promising area of follow-up research is to identify the specific genetic and biological mechanisms behind the observed differences in brain development. Continue reading

Stoners Dumber If They Start On Pot Younger, Small Study Finds


Or as Harvard’s McLean Hospital puts it, marijuana users show greater cognitive deficits if they start smoking at a younger age. McLean researcher Staci A. Gruber is presenting those findings today at the huge Society for Neuroscience annual meeting in San Diego — and she’ll be featured today on Radio Boston’s 3 p.m. show. (Call in! If you can focus long enough to remember your question, that is…)

Dr. Gruber and her team found that on tests of “executive function” — higher-order brain skills that include planning and carrying out mental tasks — pot-users who started smoking before age 16 made twice as many mistakes as those who started later.

They also found that users who started younger tended to smoke far more than the later starters — three times as much pot, and twice as often — and that their brains “lit up” differently in the scanner, suggesting significant neural change.

This from McLean:

“We have to be clear about getting the message out that marijuana isn’t really a benign substance,” [Dr. Gruber] said. “It has a direct effect on executive function. The earlier you begin using it, and the more you use of it, the more significant that effect.”

The study included 33 chronic marijuana smokers and 26 control subjects who did not smoke marijuana. They were given a battery of neurocognitive tests assessing executive function, including the Wisconsin Card Sorting Test, which involves sorting different cards based on a set of rules given. During the test, the rules are changed without warning and subjects must adjust their responses to the new rules. Continue reading