When good habits go bad: Neuroscientist seeks roots of obsessive behavior, motion disorders

Learning, memory and habits are encoded in the strength of connections between neurons in the brain, the synapses. These connections aren't meant to be fixed, they're changeable, or plastic.

Duke University and neuroscientist Nicole Calakos studies what happens when those connections aren't as adaptable as they should be in the basal ganglia, the brain's "command center" for turning information into actions.

"The basal ganglia is the part of the brain that drives the car when you're not thinking too hard about it," Calakos said. It's also the part of the brain where neuroscientists are looking for the roots of obsessive-compulsive disorder, Huntington's, Parkinson's, and aspects of .

In her most recent work, which she'll discuss Saturday morning, Feb. 16 at the American Association for the Advancement of Science annual meeting in Boston, Calakos is mapping the defects in circuitry of the basal ganglia that underlie compulsive behavior. She is studying mice that have a synaptic defect that manifests itself as something like obsessive-compulsive behavior.

Calakos' former colleague Guoping Feng developed the mice at Duke before moving to the McGovern Institute for at MIT, where he now works. Feng was exploring the construction of synapses by knocking out genes one at a time. One set of mice ended up with facial lesions from endlessly grooming themselves until their faces were rubbed raw. When examining synaptic activity in the of these mice, Calakos' group discovered that metabotropic glutamate receptors, or mGluRs, were overactive and this in turn, left their synapses less able to change. Scientists think overactivity of these receptors can cause many aspects of the Fragile X mental retardation.

"It's an example of synaptic plasticity going awry," Calakos said. "They're stuck with less adaptable ." Calakos is now using the mice to determine whether drugs that inhibit mGluRs can be used to improve their behavior and testing whether the circuit defects are a generalizable explanation for similar behaviors in other mouse models. This work may then lead to new understandings for compulsive behaviors and new treatment opportunities.

add to favorites email to friend print save as pdf

Related Stories

Re-creating autism, in mice

Mar 21, 2011

(PhysOrg.com) -- By mutating a single gene, researchers at MIT and Duke have produced mice with two of the most common traits of autism — compulsive, repetitive behavior and avoidance of social interaction.

Positive feedback in the developing brain

May 16, 2012

(Medical Xpress) -- When an animal is born, its early experiences help map out the still-forming connections in its brain. As neurons in sensory areas of the brain fire in response to sights, smells, and sounds, ...

Researchers uncover steps in synapse building, pruning

Nov 16, 2011

Like a gardener who stakes some plants and weeds out others, the brain is constantly building networks of synapses, while pruning out redundant or unneeded synapses. Researchers at The Jackson Laboratory led by Assistant ...

Scientists find molecular glue needed to wire the brain

Dec 08, 2010

(PhysOrg.com) -- Yale University researchers have found that a single molecule not only connects brain cells but also changes how we learn. The findings, reported in the December 9 issue of the journal Neuron, may he ...

Recommended for you

Helping autistic kids read, write and communicate

Dec 04, 2014

The boy is delighted. You can see it in his eyes—his enthusiasm for the task, his pride in his ability. Indeed, Max has good reason to be proud: At age three, he is reading. And at this precise moment, ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.