Dana Foundation Blog

New SfN Website, BrainFacts.org, Launches

The World Wide Web welcomes a new site today with the launch of BrainFacts.org. Created by the Society for Neuroscience, the site aims to present neuroscience information to the public in an accessible way. BrainFacts.org seeks to share what neuroscientists know, explore what they don’t yet know fully, and discuss how today’s research advances understanding.

The site provides a wide range of content about the brain, covering neuroscience basics as well as getting into more detail on topics like disease, memory, and language. There are sections of the site geared towards educators, policymakers, and the press. The content is reviewed by scientists for accuracy.

New Vocabulary

We love to learn, and the researchers and presenters at the Society for Neuroscience Annual Meeting give us more than we could possibly handle. Every year, along with developments in familiar areas like cognition, motor and sensory systems, and development, we also pick up on new areas of research—and new words.

Here's a short list from the news around this year's meeting. Are we behind the curve, or are they new to you, too?

Angiophagy: A cellular process small blood vessels use to clear clots. Vesicles envelop the clot and expel it through the cell wall. In a young brain, the vessels survive, but in older (mouse) brains, the vessels often die and surrounding vessels can suffer permanent injury. This may be why stroke recovery can be more difficult in older people, suggested Jaime Grutzendler of Yale during one of the press conferences. (abstract 891.17/DD23) 

Convergent science: When people pursuing two directions of research in a lab discover that each has a relation to (or complements) the other. Special lecturer Andrew Feinberg used this word to describe what happened in his lab when they investigated how gene expression varies in cancer cells and in a (they thought) different process in normal cell tissues.

Exposome: The soup your genome is in, what it affects, and what can affect it (environment, diet, social factors). These effects change over time and may explain how a person is predisposed to certain diseases at various stages of life. (The epigenome is changes to the genome itself due to environmental factors or your own thinking.) This comes from NIMH director Thomas Insel's post on "precision medicine"; we heard him talk at the NIH press conference during the meeting.

Pharmacogenetics: Applying genetic technologies (genome sequencing, methods of switching genes on and off) to the development of new drugs and the discovery of new uses for current drugs. We first saw this in a post about the History of Neuroscience lecture given by Dana Alliance member Anne Young on neurodegenerative diseases.

STEP: It’s a protein (full name: striatal-enriched protein tyrosine phosphatase) that regulates synaptic connections when working properly. It was the star of the press conferences this year: Levels of STEP are abnormally high in Fragile X, schizophrenia, and other neuropsychiatric disorders. In animal research, reducing STEP levels has led to positive behavioral differences. 

Telempathy: Ability to feel another's emotions through the use of brain technologies. We heard this during a talk by writer Michael Chorost at an auxiliary event, the International Neuroethics Society (INS) meeting. Chorost's latest book is World Wide Mind: The Coming Integration of Humanity, Machines, and the Internet.

-- Nicky Penttila

Generating Obesity

The obesity epidemic was the topic of the Public Advocacy Forum at the Society for Neuroscience annual meeting on Wednesday, and it was nearly two hours of scary data with a little bit of hope.

You've probably already heard many of the statistics: In the United States, 34 percent of adults over age 20 are classified as obese (body mass index score of 30+, normal is 18.5-25); their healthcare issues cost an estimated $270 billion each year. In the past 20 years, we went from no state having an obesity rate over 14 percent to no state having an obesity rate under 20 percent. Fifteen percent of kids today are overweight, with another 13 percent obese—and 4 percent obese II (BMI of 35+). And on and on.

But for me, the scariest data was on how a tendency toward obesity—and related risks for diabetes, hypertension, and other troubles—may be transmitted parent to child, and on to grandchild. And it's not all on the moms, either.

Research presented by Teresa Reyes of the University of Pennsylvania suggested that maternal obesity leads to the risk of higher BMI, fat accumulation, hyperglycemia, insulin resistance, and heart disease. "Some of the effects are brain-related," she said, "and relate to later risk of obesity." Researchers have found these results in rodents and other primates, as well as humans.

In rats, said Reyes, "A maternal 'junk food' diet in pregnancy and lactation promotes an exacerbated taste for junk food and a greater propensity for obesity in offspring," who show a stronger-than-average preference for sugar and fatty foods. On the other hand, in humans, mothers who drank carrot juice during pregnancy and lactation produced babies who, in the main, also preferred the taste of carrots.

A mother's prenatal food choices affect not only her child; the child's sperm or eggs also develop in the womb, and will pass the traits on to the grandchildren. In the rat studies, if the high-fat-eating mother has a boy, its offspring also will be fatter, no matter the size of his mate.

Reyes says there are a lot of questions still to be answered. Are these changes reversible? What is the critical period (before pregnancy, gestation, first trimester)? Is one sex more vulnerable to another for certain risk factors? "Nearly every study is finding important sex differences," she said.

Surgeon John Kral, a professor at SUNY Downstate Medical Center, described research in macaque monkeys that suggests that a pregnant mother's "food insecurity" can create brain changes that can lead to obesity. Monkey moms who were fed irregularly for only 14 days of their 165-day gestation period gave birth to baby monkeys who grew up to be obese. About 15 percent of people in the United States last year reported "food insecurity"; Kral suggested we might investigate whether the pattern fits for human offspring, as well. (See also the story of the Dutch Hunger Winter.)

"Acute and periodic undernutrition build adaptive mechanisms," Kral said. We have a lot of adaptive mechanisms, but not for obesity. "There are no physiological ways of getting rid of that excess."

Kral also described the effects of what he called "a low-fat diet imposed through surgery," involving gastric bands or diversion surgery. Researchers studied women who had given birth, had the surgery, then (usually years later) given birth again. Children born pre-surgery showed high BMIs and high rates of obesity, hypertension, and other metabolic problems. Children born after surgery showed only a small reduction in average BMI compared with their older siblings—but no higher risk for metabolic problems or obesity.

"We've followed them into their 20s," Kral said. "Obesity surgery improves maternal health, fetal outcome, and child health. It prevents obesity." He's not suggesting we run out and all get lap-banded, though: Obesity surgery carries health risks. (See more on pregnancy after bariatric surgery.)

Kral suggests that every fertile woman have pre-conception education, explaining how metabolism works and how her decisions will affect any future children. Women should start having prenatal visits as soon as they know they are pregnant, not wait three or four months for a first visit. Kral also suggests that as soon as possible after conception, women receive food vouchers until they give birth. "Then food insecurity is taken out of the equation."

Parents want their kids to do well, but they may not realize how their pre-natal food choices can affect the future.

"The kids who are the least fit score the worst on standardized tests," no matter their socioeconomic staus, said Antonio Convit of New York University, including tests of intellectual function, IQ, reading, spelling, working memory, attention, and focus. "I'm not suggesting that these kids are stupid, but they don't do as well on cognitive tasks. Who would want their kid to perform 10 percent less than his potential just because he's carrying extra weight?"

David S. Ludwig of Harvard and Bruce McEwen of Rockefeller University also took part in the forum, which was organized by McEwen. Video of the full 2-hour session is on SfN's YouTube page.

--Nicky Penttila

Sex and Brain Science

Is the study of sex differences gaining traction in neuroscience? It was the topic of the very first Social Issues Roundtable at the Society for Neuroscience, in 1983, and it was the topic again this year. Thirty years ago, it didn't seem to affect the crowd, though—research continued to focus on males (usually excluding females, whose additional monthly cycles were sometimes thought to dirty the results and be too complicated to take into account).

But now, "I'm starting to believe we've hit some sort of critical mass in the past decade," said Larry Cahill of the University of California, Irvine. "I think it's going to start changing rapidly."

Cahill is in a position to know. He's been talking about sex differences in research for decades, often to deaf ears, he said. Sex differences in the brain are real, and critically important, but news and information about them often gets misinterpreted. Media and careless people often overgeneralize from close studies to the greater population, to the point where "male brains" and "female brains" can seem different species.

Cahill said he has heard people who would never generalize the results of male-only rat studies to female rats, then go on and generalize them to people—both men and women.

In terms of behavior research, too, "there is a tendency for people to light up all their gender schemas," said Melissa Hines of Cambridge University. Just because non-human mammals show sex-typed preferences when they play with toys doesn't mean human boys are doomed to a truck-fixation, for example. Data from people who have gender identity disorder suggests that people are affected by hormones, but also how they are raised and where they were raised (and when—pink was considered the "boy" color in the U.S. 100 years ago).

Nevertheless, "there are sex differences at all levels of brain function... down to the molecular level," Cahill said. For example, a manner of apoptosis (how cells die and are cleared away) differs by sex. Another recent robust finding is in how emotional memories are processed. "It's just ubiquitous in brain science," he said.

Different also does not mean unequal, Cahill argued. For example, would you say "2 plus 3" does not equal the very different "10 minus 5"? Male and female brains certainly have some differences, but the results they produce, in cognition and behavior, may well be equivalent.

"If two populations are different and you want to treat them equally, you may have to treat them differently," Cahill said.

"I'm also against the misconceptions at this meeting, and I know about them because I shared them," Cahill said. It is not too hard to take sex differences into account when planning research—all research takes differences into account. And it doesn't always make things more complicated: "I am unaware that the average effect size in sex difference research is any different than any other area of brain reseach," he said

"The real peril... is that people will continue not to study sex differences. For me, it means the burden of proof has shifted. It's up to you to justify why you're not taking it into acount," he told the scientists in the room.

Searching the SfN database for posters, workshops, and sessions including the term "sex+difference," I got more than 150 hits, including sessions on neural development, immunity, stress, memory, antidepressant response, and obesity. On the other hand, there were more than 16,000 posters and sessions presented during the meeting.

Also speaking during the roundtable were Janet Hyde of the University of Wisconsin and  Maryjane Wraga of Smith College; the event was organized by Lise Eliot of Chicago Medical School of Rosalind Franklin University of Medicine and Science. I had to leave for another lecture halfway through the roundtable's Q&A session, but I heard later it got a bit heated (see more on Slate and at Psychneuro's blog). 

--Nicky Penttila

Advances in Stroke Research

Two presentations on stroke at a Society for Neuroscience press conference on Tuesday revealed a possible strategy to mitigate stroke’s effects and a brain mechanism at play.

Ron Frostig, at UC Irvine, described his lab’s research into using sensory and sound stimulation as a protective measure against stroke. As Dr. Frostig explained, 88 percent of strokes are ischemic, caused by a blockage of blood flow usually to the middle cerebral artery, or MCA.

Dr. Frostig and his colleagues began their experiment by stimulating the whisker of a rat for about five minutes. Then, they caused a permanent occlusion, or blockage, to the animal’s MCA. Within two hours of the occlusion, they again stimulated a whisker for less than five minutes.

The stimulation proved completely protective to brain injury in the rat.

Next, Dr.  Frostig replaced whisker stimulation with auditory stimulation. This, too, was completely protective. As Dr. Frostig concluded, “sensory-induced activation triggers compensatory self-protective mechanisms.”

Could this research translate to humans? Dr. Frostig pointed out that, with the notable exception of Salvador Dali, most of us don’t have whiskers. But he believes that auditory and sensory stimulation could have a protective effect.  Stimulation has to impact the area of the brain affected by the stroke—it’s not always possible to know where that is—and must occur within the two hour window. If done too late, stimulation could be harmful. But if you know when a stroke began, about five minutes of auditory and sensory stimulation could be beneficial while waiting for an ambulance to arrive.

Jaime Grutzendler and his colleagues at Yale University Medical School used confocal microscopy to identify a brain process that clears clots from small blood vessels.

By imaging a tiny vessel in a living mouse brain, Dr. Grutzendler saw a vesicle envelop a clot and expel it through the cell wall. In a young brain, the vessels survive. In an older brain, the vessels often die and surrounding vessels suffer permanent injury. This may be why stroke recovery can be more difficult in older people.

Dr. Grutzendler and his colleagues named the process angiophagy, and found that it begins one to three days post-stroke. He hopes that this finding—and future research into how the mechanisms involved work—could lead to new treatments for blockages in the brain, heart, retina, and other organs.

--Johanna Goldberg