image: A family of prairie voles. view more
Credit: Todd Ahern
Almost everyone will experience the loss of a loved one at some point, whether it's the break-up of a romantic relationship or the death of a close friend or family member.
Most are able to climb out of their bereavement with time. But for the roughly 10 percent of people who suffer from what's known as "complicated grief," intense mourning can persist for years.
Zoe Donaldson wants to find out why.
"Imagine what it would be like to wake up every single morning and feel the same way you did the day after you found out you lost someone," explains Donaldson, an assistant professor of behavioral neuroscience at University of Colorado Boulder.
With help from a colony of 100 prairie voles and a $1.5 million High-Risk, High-Reward grant announced Tuesday by the National Institutes of Health, Donaldson hopes to shed new light on the precise neural mechanisms that allow us to form close social bonds and gradually recover - or not - when they're severed.
The findings could help inform treatment for people who have trouble forging emotional connections, such as those with autism, as well as those unable to rebound when those connections are cut.
"If you think about some of the most important events that take place in life, they fall around social relationships. We fall in love, we get married, we have kids, we lose someone close to us," says Donaldson. "These studies will help reveal the biological basis of the emotions that help maintain those relationships."
Donaldson focuses her research on prairie voles, small, furry rodents that - unlike mice, rats and about 97 percent of mammals - share a unique quality with humans: They tend to be monogamous.
"Prairie voles in the wild will meet, mate and stay together for a lifetime," she says.
Previous research by has already illuminated hormonal differences:
Prairie voles have more and differently distributed receptors for a hormone called vasopressin than their promiscuous cousins, the meadow and montane voles.
Oxytocin, a hormone associated with trust and empathy, has also been shown to play a key role in bond formation in both prairie voles and humans.
Donaldson now wants to take such research further, using cutting-edge imaging techniques and instruments that allow her to stimulate certain brain regions of the voles as they interact to study precisely which neurons are at play when the animals form a bond, or that bond is disrupted.
Such research is critically needed, says Katherine Shear, a professor of psychiatry at Columbia University who specializes in bereavement and reached out to Donaldson to suggest she study it.
Shear notes that current antidepressant medications seldom help people who have trouble getting over the loss of a loved one.
"Close attachments contribute importantly to many of the psychological problems individuals face, yet there is very little neurobiological research informing this question of what happens in the brain when we lose someone," says Shear.
Donaldson's award (#DP2MH119427) is among 58 NIH Director's New Innovator awards announced Tuesday to fund "extraordinarily creative scientists proposing highly innovative research to address major challenges in biomedical science."
"My hope is that by understanding what happens normally when we adapt to a loss we can gain insight into how we can facilitate or stimulate this normal adaptive process" she says. "Losing someone you love shouldn't mean losing out on joy for the rest of your life."
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