Do women have the brains to be great scientists?

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Hopkins, an MIT professor, walked out when the president of Harvard implied that women scientists were innately less talented than male ones. Now, the Nobel Prizes give her the last laugh.

It’s been a spectacular week for women in science, and a bad week for “the Larry Summers hypothesis." In 2005, while president of Harvard, he suggested that women are inherently worse than men at math, science and engineering, particularly at the highest levels. This week three women won Nobel prizes in science: two in medicine and one in chemistry. That achievement should put the nail in the coffin of the question Summers raised: Can many women really be great scientists?

When I was a graduate student in biology at Harvard 40 years ago, my colleagues used to sit around discussing whether girls were capable of being great scientists. Could a woman really win a Nobel Prize in molecular biology? Men I knew wondered if women’s brains were so different from men's that they couldn’t make the creative breakthroughs that lead to the greatest discoveries. That’s what I wondered too. Sure, there was Madame Curie--but there were too few Madame Curies to convince us she was anything but an exception.

It turns out that back then, in the dark ages for women in science, we were asking the wrong question. Instead of asking if women's brains were inferior, we should have asked why there were so few women at the major research universities and laboratories that breed future Nobel laureates.

In the late 1960s there were essentially no women on the science faculties of places like Harvard, Cal Tech and MIT (where I now work as a professor of molecular biology). Things began to change dramatically in the early 1970s, thanks to affirmative action measures taken under Richard Nixon. Those included the “Shultz regs” (George Shultz was Nixon's Secretary of Labor), which required universities to hire women onto their faculties or risk losing their federal funding. The Nobel prizes in medicine this week are the end result of those laws. Nobelist Elizabeth Blackburn joined the Berkeley faculty in 1978 and Nobelist Carol Greider was her star graduate student. (The third new laureate is Ada Yonath, an Israeli.)

Until about 10 years ago, women still comprised only five percent of the science faculty at Harvard and eight percent at MIT, with similar numbers at other high-powered research universities. (Today 17 percent of the MIT science faculty are women, as a result of specific efforts by the MIT administration in collaboration with senior women faculty.) But even those paltry numbers from 10 years ago have been enough to start yielding female Nobelists. In fact, if we assume that female faculty win these prizes at the same rate as male faculty, then only in the past couple of years have there been enough women employed at MIT to begin producing Nobel laureates.

Brain Scans Reveal What You’ve Seen

Scientists are one step closer to knowing what you’ve seen by reading your mind.

Having modeled how images are represented in the brain, the researchers translated recorded patterns of neural activity into pictures of what test subjects had seen.

Though practical applications are decades away, the research could someday lead to dream-readers and thought-controlled computers.

“It’s what you would actually use if you were going to build a functional brain-reading device,” said Jack Gallant, a University of California, Berkeley neuroscientist.

The research, led by Gallant and Berkeley postdoctoral researcher Thomas Naselaris, builds on earlier work in which they used neural patterns to identify pictures from within a limited set of options.

The current approach, described Wednesday in Neuron, uses a more complete view of the brain’s visual centers. Its results are closer to reconstruction than identification, which Gallant likened to “the magician’s card trick where you pick a card from a deck, and he guesses which card you picked. The magician knows all the cards you could have seen.”

In the latest study, “the card could be a photograph of anything in the universe. The magician has to figure it out without ever seeing it,” said Gallant.

To construct their model, the researchers used an fMRI machine, which measures blood flow through the brain, to track neural activity in three people as they looked at pictures of everyday settings and objects.

As in the earlier study, they looked at parts of the brain linked to the shape of objects. Unlike before, they looked at regions whose activity correlates with general classifications, such as “buildings” or “small groups of people.”

Once the model was calibrated, the test subjects looked at another set of pictures. After interpreting the resulting neural patterns, the researchers’ program plucked corresponding pictures from a database of 6 million images.

Frank Tong, a Vanderbilt University neuroscientist who studies how thoughts are manifested in the brain, said the Neuron study wasn’t quite A pure, draw-from-scratch reconstruction. But it was impressive nonetheless, especially for the detail it gathered from measurements that are still extremely coarse.

The researchers’ fMRI readings bundled the output of millions of neurons into single output blocks. “At the finer level, there is a ton of information. We just don’t have a way to tap into that without opening the skull and accessing it directly,” said Tong.

Gallant hopes to develop methods of interpreting other types of brain activity measurement, such as optical laser scans or EEG readings.

He mentioned medical communication devices as a possible application, and computer programs for which visual thinking makes sense — CAD-CAM or Photoshop, straight from the brain.

Such applications are decades away, but “you could use algorithms like this to decode other things than vision,” said Gallant. “In theory, you could analyze internal speech. You could have someone talk to themselves, and have it come out in a machine.”

Where Does Sex Live in the Brain? From Top to Bottom.

Neuroscientists explore the mind's sexual side and discover that desire is not quite what we thought it was.

On April 11, 1944, a doctor named T. C. Erickson addressed the Chicago Neurological Society about a patient he called Mrs. C. W. At age 43 she had started to wake up many nights feeling as if she were having sex—or as she put it to Erickson, feeling “hot all over.” As the years passed her hot spells struck more often, even in the daytime, and began to be followed by seizures that left her unable to speak. Erickson examined Mrs. C. W. when she was 54 and diagnosed her with nymphomania. He prescribed a treatment that was shockingly common at the time: He blasted her ovaries with X-rays.

Despite the X-rays, Mrs. C. W.’s seizures became worse, leaving her motionless and feeling as if an egg yolk were running down her throat. Erickson began to suspect that her sexual feelings were emanating not from her ovaries but from her head. Doctors opened up her skull and discovered a slow-growing tumor pressing against her brain. After the tumor was removed and Mrs. C. W. recovered, the seizures faded. “When asked if she still had any ‘passionate spells,’” Erickson recounted, “she said, ‘No, I haven’t had any; they were terrible things.’”

Mrs. C. W.’s experience was rare but not unique. In 1969 two Florida doctors wrote to the journal Neurology about a patient who experienced similar spells of passion. She would beat both hands on her chest and order her husband to satisfy her. Usually the woman would come to with no memory of what had just happened, but sometimes she would fall to the floor in a seizure. Her doctors diagnosed her with epilepsy, probably brought on by the damage done to parts of her brain by a case of syphilis. More recently, in 2004, doctors in Taiwan described a woman who complained of orgasms that swept over her when she brushed her teeth. Shame kept her silent for years, until her episodes also caused her to lose consciousness. When the doctors examined her, they diagnosed her with epilepsy as well, caused by a small patch of damaged brain tissue.

Each of these stories contains a small clue about the enigmatic neuroscience of sex. A hundred years ago Sigmund Freud argued that sexual desire was the primary motivating energy in human life. Psychologists and sociologists have since mapped the vast variations in human sexuality. Today pharmaceutical companies make billions bringing new life to old sex organs. But for all the attention that these fields of research have lavished on sex, neuroscientists have lagged far behind. What little they knew came from rare cases such as Mrs. C. W.’s.

The case studies do make a couple of things clear. For starters, they demonstrate that sexual pleasure is not just a simple set of reflexes in the body. After all, epileptic bursts of electricity in the brain alone can trigger everything from desire to ecstasy. The clinical examples also point to the parts of the brain that may be involved in sexual experiences. In 2007 cognitive neuroscientist Stephanie Ortigue of Syracuse University and psychiatrist Francesco Bianchi-Demicheli of the Geneva University Psychiatric Center reviewed the case of Mrs. C. W. and 19 other instances of spontaneous orgasms. In 80 percent of them, doctors pinpointed epilepsy in the temporal lobe.

The temporal lobe is still a big piece of real estate, though. To zoom in on the regions associated with sexuality, neuroscientists needed to scan people’s brains while they were having sex-related thoughts. But using brain scans to study sex is not easy. Most brain imaging technology works the way cameras did in the 19th century: If you want a clear picture, you have to hold very still. Even then, brain scans provide meaningful information only in carefully designed experiments. If you want to find the parts of the brain that are crucial for reading, for instance, you can’t just take pictures of people’s brains as they read; the visual cortex carries out many functions other than reading. Scientists therefore have to craft experiments that allow them to compare what happens to brains during reading with what happens when people look at random strings of letters or checkerboard patterns. The same precision is required to study sex in the brain.

As a result, the first imaging studies of sex in the brain have appeared only in the past few years. Serge Stoléru, a neuroscientist at Pierre and Marie Curie University in France, published one on sexual desire in 2003. He and his colleagues showed a series of pictures and films—some erotic, some ordinary—to 15 men. To record the activity in the subjects’ brains, the scientists used PET scans: They injected radioactive tracers into the volunteers and then tracked how the tracers moved in the brain. The radioactive signal accumulated in areas where neurons became active, as their energy was replenished by the surrounding blood vessels.

Eight of the men were ordinary, sexually speaking. The other seven suffered from hypoactive sexual desire disorder. People with this condition rarely experience sexual desires or fantasies. Stoléru and his colleagues found clear-cut differences between the two groups. In particular, a patch of neurons near the front of the brain—a region called the medial orbitofrontal cortex—was active in the desire-impaired men but quiet in the normal ones. Among its jobs, the medial orbitofrontal cortex keeps our emotions from getting out of control. Perhaps men with hypoactive sexual desire disorder couldn’t feel desire because their brains were keeping their emotions bottled up.

Unfortunately, PET scans take several minutes to capture a single image. A lot can happen in that time, especially when sex is involved. So Stoléru and other scientists have switched to a faster method, functional MRI (fMRI), which monitors the flow of blood to active neurons by measuring levels of oxygen in the brain. This technique can capture an image of the working brain in just a couple of seconds and locate areas of activity down to a millimeter or so—about one-twentieth of an inch.

The parts of the brain that light up during sexual experiences are associated with some of our most sophisticated forms of thought.

Using fMRI, scientists have pinpointed a number of regions of the brain that kick in when people feel sexual desire. As expected, several of them are in the temporal lobe. One of those regions, the amygdala, orchestrates powerful emotions. Another, the hippocampus, manages our memories. It may become active as we associate sights and smells with past sexual experiences. But despite what Freud thought, sexual experiences are not just a matter of primal emotions and associations. The parts of the brain that light up in the fMRI scans include regions that are associated with some of our most sophisticated forms of thought. The anterior insula, for instance, is what we use to reflect on the state of our own bodies (to be aware of the sensation of butterflies in the stomach, say, or of lightness in the head). Brain regions that are associated with understanding the thoughts and intentions of other people also seem linked with sexual feelings.

Even fMRI studies are not fast enough to catch the flow of activity, however. They cannot tell us which regions of the brain become active first, which later. So Ortigue and Bianchi-Demicheli are updating one of the oldest brain-monitoring technologies. For decades scientists have taped electrodes onto people’s scalps to record their brain activity and create a readout called an electroencephalogram, or EEG. In the past this approach offered a blurry picture of what was going on in the subject’s brain. An electrode on the scalp can pick up electrical activity only after it has spread beyond the skull, getting weakened and smeared along the way. But the EEG process is fast; it can capture 1,000 snapshots a second.

Human Brain Could Be Replicated In 10 Years, Researcher Predicts

A model that replicates the functions of the human brain is feasible in 10 years according to neuroscientist Professor Henry Markram of the Brain Mind Institute in Switzerland. "I absolutely believe it is technically and biologically possible. The only uncertainty is financial. It is an extremely expensive project and not all is yet secured."

The apparent complexity of the human mind is not a barrier to building a 'replica' brain claims Professor Markram. "The brain is of course extremely complex because it has trillions of synapses, billions of neurons, millions of proteins, and thousands of genes. But they are still finite in number. Today's technology is already highly sophisticated and it allows us to reverse engineer the brain rapidly." An example of the capability already in place is that today's robots can do screenings and mappings tens of thousands of times faster than human scientists and technicians.

Another hurdle on the path to a model human brain is that 100 years of neuroscience discovery has led to millions of fragments of data and knowledge that have never been brought together and exploited fully. "Actually no one even knows what we already understand about the brain," says Professor Markram. "A model would serve to bring this all together and then allow anyone to test whatever theory you want about the brain. The biggest challenge is to understand how electrical-magnetic-chemical patterns in the brain convert into our perception of reality. We think we see with our eyes, but in fact most of what we 'see' is generated as a projection by your brain. So what are we actually looking at when we look at something 'outside' of us?"

For Professor Markram, the most exciting part of his research is putting together the hundreds of thousands of small pieces of data that his lab has collected over the past 15 years, and seeing what a microcircuit of the brain looks like. "When we first switched it on it already started to display some interesting emergent properties. But this is just the beginning because we know now that it is possible to build it. As we progress we are learning about design secrets of our brains which were unimaginable before. In fact the brain uses some simple rules to solve highly complex problems and extracting each of these rules one by one is very exciting. For example we have been surprised at finding simple design principles that allow billions of neurons to connect to each other. I think we will understand how the brain is designed and works before we have finished building it."

The opportunities for this neuroscience research challenge are immense explains Professor Markram: "A brain model will sit on a massive supercomputer and serve as a kind of educational and diagnostic service to society. As the industrial revolution in science progresses we will generate more data than anyone can track or any computer can store, so models that can absorb it are simply unavoidable. It is also essential to build models when it comes to treating brain diseases affecting around two billion people. At present, there is no brain disease for which we really understand what has gone wrong in the processing, in the circuits, neurons or synapses. It is also important if we are to replace the need for the millions of animal experiments each year for brain research."

Source & Credits: Sciencedaily.com