The science of a broken heart

Valentine's Day is a time to celerate the power of love, and all the joy it can bring. But Cupid's arrow is doubled-edged: We have all had our hearts broken, or know someone who has.

"It's a popular belief that the heart is the center of emotion and can actually break. There is some truth to that," says Viola Vaccarino, chair of epidemiology at Emory's Rollins School of Public Health. Watch the above video to learn more.

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The eternal tensions of religion and science

A painting titled "Astronomer Copernicus, Conversation with God," by artist Jan Matejko.

Why did the Catholic Church put Galileo on trial for heresy when he argued that the Earth revolves around the sun? Why do many people today not believe in evolution, despite overwhelming scientific evidence?

The tension between religion and science is not something new, nor is it likely to ever go away, despite accumulating knowledge about the natural world, says Robert McCauley, director of Emory’s Center for Mind, Brain and Culture. His latest book is called “Why Religion is Natural and Science is Not.”



“Religion is cognitively natural and comes easily to the human mind. It trafficks in the kind of ideas that minds like to think,” McCauley explains. “By contrast, science is always pulling together representations and models and ideas that are quite contrary to our normal assumptions about the world.”

In other words, science often butts heads with common sense.

“A classic illustration is, even though it’s the case that we think we are all Copernicans and everyone understands that the Earth circles the sun, the fact of the matter is when we look at the night sky, we don’t see the world as Copernican,” McCauley says. “Once you undergo the intellectual exercise to see the world as Copernican, it’s startlingly unnerving.”

"Galileo Facing the Roman Inquisition," a painting by Christiano Banti.

On the other hand, the seeds of religious belief may be inherent in our minds as far back as infancy.

“We are having to figure out what other people are thinking and why they’re doing what they’re doing in order to anticipate things that they might do, whether it’s for survival in a complex social setting or a more fundamental issue of detecting agents that may want to have you for lunch, ” McCauley says.

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Why religion is natural and science is not

Metaphors activate sensory areas of brain

Regions of the brain activated by hearing textural metaphors are shown in green. Yellow and red show regions activated by sensory experience of textures visually and through touch.

By Quinn Eastman, Woodruff Health Sciences Center

When a friend tells you she had a rough day, do you feel sandpaper under your fingers? The brain may be replaying sensory experiences to help understand common metaphors, new research suggests.

Linguists and psychologists have debated how much the parts of the brain that mediate direct sensory experience are involved in understanding metaphors. George Lakoff and Mark Johnson, in their landmark work "Metaphors we live by," pointed out that our daily language is full of metaphors, some of which are so familiar (like "rough day") that they may not seem especially novel or striking. They argued that metaphor comprehension is grounded in our sensory and motor experiences.

New brain imaging research reveals that a region of the brain important for sensing texture through touch, the parietal operculum, is also activated when someone listens to a sentence with a textural metaphor. The same region is not activated when a similar sentence expressing the meaning of the metaphor is heard.

The results were published online this week in the journal Brain & Language.

"We see that metaphors are engaging the areas of the cerebral cortex involved in sensory responses even though the metaphors are quite familiar," says senior author Krish Sathian, professor of neurology, rehabilitation medicine and psychology at Emory University. "This result illustrates how we draw upon sensory experiences to achieve understanding of metaphorical language."

Seven college students who volunteered for the study were asked to listen to sentences containing textural metaphors as well as sentences that were matched for meaning and structure, and to press a button as soon as they understood each sentence. Blood flow in their brains was monitored by functional magnetic resonance imaging. On average, response to a sentence containing a metaphor took slightly longer (0.84 vs 0.63 seconds).

In a previous study, the researchers had already mapped out, for each of these individuals, which parts of the students' brains were involved in processing actual textures by touch and sight. This allowed them to establish with confidence the link within the brain between metaphors involving texture and the sensory experience of texture itself.

"Interestingly, visual cortical regions were not activated by textural metaphors, which fits with other evidence for the primacy of touch in texture perception," says research associate Simon Lacey, the first author of the paper.

The researchers did not find metaphor-specific differences in cortical regions well known to be involved in generating and processing language, such as Broca's or Wernicke's areas. However, this result doesn't rule out a role for these regions in processing metaphors, Sathian says. Also, other neurologists have seen that injury to various areas of the brain can interfere with patients' understanding of metaphors.

"I don't think that there's only one area responsible for metaphor processing," Sathian says. "Actually, several recent lines of research indicate that engagement with abstract concepts is distributed around the brain."

"I think our research highlights the role of neural networks, rather than a single area of the brain, in these processes. What could be happening is that the brain is conducting an internal simulation as a way to understand the metaphor, and that's why the regions associated with touch get involved. This also demonstrates how complex processes involving symbols, such as appreciating a painting or understanding a metaphor, do not depend just on evolutionarily new parts of the brain, but also on adaptations of older parts of the brain."

Sathian's future plans include asking whether similar relationships exist for other senses, such as vision. The researchers also plan to probe whether magnetic stimulation of the brain in regions associated with sensory experience can interfere with understanding metaphors.

The research was supported by the National Institutes of Health and the National Science Foundation.

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African-Americans and the toll of AIDS

HIV-AIDS is the third leading cause of death among African-American men and women between the ages of 35 and 44. Today is National Black HIV/AIDS Awareness Day, which aims to lower that tragic statistic through education, testing, involvement and treatment of the disease.

African Americans face the most severe burden of HIV of all racial groups in the United States. They disproportionately represent both new infections and fatalities, says Drenna Waldrop-Valverde, an investigator with Emory's Center for AIDS Research, and a professor in the Nell Hodgson Woodruff School of Nursing.

"Unfortunately, in this country, race and socio-economic status are very closely tied together," says Waldrop-Valverde. She is conducting an NIH-funded study of the effects of health literacy on drug compliance in African Americans living with HIV-AIDS.

"Taking medications just as the doctor tells you to take them, day in and day out, can have a greater benefit on the health of those with HIV than nearly any other factor," Waldrop-Valverde says.

How is HIV/AIDS affecting your community? Click here to see an interactive AIDS map of the United States.

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On the trail of black flies and river blindness

The parasite that causes river blindness, Onchocerca volvulus, is transmitted through the bite of the black fly. In the above photo, the parasite can be seen emerging from the antenna of a black fly. (Credit: U.S. Department of Agriculture.)

Onchocerciasis, better known as “river blindness,” is one of the leading causes of preventable blindness in the world. More than 18 million people suffer from river blindness, the vast majority of them in Africa.

The disease is caused by parasitic worms that are spread to humans through the bite of the black fly. The symptoms include itching so severe that those infected have been known to claw their skin off – or even commit suicide. The disease can also harden the eye tissue, leading to permanent blindness.

A documentary called “Dark Forest Black Fly” is tracking the efforts of the Carter Center and its partners to wipe out river blindness in Uganda. If successful, Uganda may become the model for eliminating river blindness Africa-wide. (Watch the film's trailer, below.)

The filmmakers and scientists involved will describe their on-the-ground experiences of this historic public health effort on Tuesday, February 7, at the Carter Center in Atlanta. The program will include exclusive footage from “Dark Forest Black Fly,” to be completed this year. Click here for details of the event.

And click here to visit the Science Scene, where you can learn about more great science events at Emory and in metro Atlanta.