A group of researchers in San Francisco published a paper in this week's Nature that explores one of the many mysteries about pain: Why do light touches near a recent injury feel so painful? The answer is more complicated than you might think. These post-trauma pains, called "mechanical pain," may be caused by a different mechanism than pain associated with injury itself. The researchers discovered that mechanical pain sensations are delivered from the injury site to the spinal cord via a chemical process that can easily be interrupted - just by blocking production of a protein called VGLUT3.

They based their analysis on experiments that proved mice lacking VGLUT3 experienced far less mechanical pain than their VGLUT3-producing cohort.

What this finding suggests is that we might be on the verge of discovering a new breed of painkillers that don't depress the entire nervous system (and fuzz out your brain), but instead interrupt specific pain pathways. In essence, you'd have a highly-targeted painkiller that would prevent your injuries from hurting while they heal. You could dull that pain without dulling your mind - and hopefully without addiction.

The researchers have yet to test on humans, but they do suggest that this could be a promising area of research for pain management.

via Nature

Image of VGLUT3 in inner ear cells (it's in red) via Human Molecular Genetics

Chorost's article is about the dawning of the age of "optogenetics," a field where scientists stimulate neurons (such as those in your brain) to fire or stop firing by genetically-engineering those neurons to respond to light. Thus, optogenetics: optics plus genetics. An inserted algae gene makes neurons fire when exposed to blue light; an inserted bacterial gene stills them when they're exposed to yellow light. Imagine being able to make the neurons responsible for chronic depression or Parkinsons stop firing with the flick of a switch. That's the dream of the scientists who are working in this field.

You've probably heard about a few optogenetic experiments over the past couple of years. Chorost describes one of the more famous ones, where students got a mouse to run counterclockwise by exposing a few neurons in its brain to blue light using fiber optic wires. He writes:

The counterclockwise-running mouse was something new - a triple fusion of animal, plant, and technology - and the students knew it was a harbinger of unprecedentedly powerful ways to alter the brain. For curing diseases, to begin with, but also for understanding how the brain interacts with the body. And ultimately for fusing human and machine.

Mice with Parkinsons symptoms who underwent optogenetic treatment also saw dramatic improvement.

And Chorost is quick to point out that Parkinsons treatments are just the beginning. Optogenetics open the door for two-way traffic between computers and the human brain. He explains:

No matter how good they get, one-way prostheses can't close the loop. In theory, two-way optogenetic traffic could lead to human-machine fusions in which the brain truly interacts with the machine, rather than only giving or only accepting orders. It could be used, for instance, to let the brain send movement commands to a prosthetic arm; in return, the arm's sensors would gather information and send it back. Blue and yellow LEDs would flash on and off inside genetically altered somatosensory regions of the cortex to give the user sensations of weight, temperature, and texture. The limb would feel like a real arm. Of course, this kind of cyborg technology is not exactly around the corner. But it has suddenly leapt from the realm of wild fantasy to concrete possibility.

Of course, there are darker fantasies that lurk here too, of perfect mind control and memory suppression. Indeed, optogenetic devices could one day lead to the consumer-grade memory-eating devices in Eternal Sunshine of the Spotless Mind. Or to Google implants in your brain.

You have to read this mind-blowing, brilliantly-written article.

via Wired

A Duke University study, conducted on November 4th, 2008, measured voters' testosterone levels before and after the winner was announced. Participants were asked to chew a piece of gum at 8pm, when the polls in North Carolina closed, and then again at 11:30pm after Obama's election was announced. By analyzing the spit samples in the gum, the researchers were able to analyze the testosterone levels of the participants.

Men generally experienced a slight drop in testosterone over the course of the night, but the participants who voted for Obama did not experience a drop in testosterone. Male voters who voted for McCain or Libertarian candidate Robert Barr, however, experienced a significantly greater drop in testosterone than would be expected. Female voters did not show a significant change in testosterone, regardless of whom they voted for.

Duke neuroscientist Kevin LaBar was excited by the indication that voters are physiologically so affected by election outcomes, and plans to perform a similar experiment involving sports instead of politics. He figures studying Duke basketball fans is a good place to start.

[Physorg]

A team led by Gero Miesenbock of the University of Oxford has been working to identify and manipulate brain cells linked to associative learning, where an animal learns to associate a certain cue with a specific outcome. There are just 12 cells in the fly brain linked with associative learning.

To determine which cells are associated with bad memories, the researchers sought to trigger those cells and, at the same time release an odor. If the fly avoided the odor in the future, they new that they had successfully rewritten the fly's memory to associate that odor with a bad experience.

They modified neurons in the flies' brains by adding a receptor that is activated by ATP. They then injected the brains with ATP placed inside a light-activated cage. They then targeted a laser at the appropriate cells, causing the release of the ATP and activating the receptors. At the same time they flashed the laser, the researchers released the odor.

Sure enough, when presented with two odors placed at equal distances from the flies, the flies who had received the laser flash avoided the odor they had been programmed to associate with bad memories. The flies effective "remembered" that something bad was associated with the smell, even though they had never experienced it themselves.

And Miesenbock believes that this could have implications for human brains as well. Researchers may be just understanding how animals learn from and adapt to mistakes, but he has every expectation that the mechanism for humans will be, on a fundamental level, the same as the mechanism for flies.

Bad memories written with lasers [BBC]

In the most recent issue of Neuron, Jack Gallant and Thomas Naselaris of the University of California, Berkeley describe their process for reconstructing images from brain scans. While previous studies have used fMRI technology to identify an image a subject has recently viewed, those studies involve a subject viewing a specific picture from a limited set and then showing them all the pictures in that set to see which one they previously viewed. Gallant and Naselaris' research is focused on reconstructing visual information based solely on readings from the brain.

The researchers have worked on identifying which parts of the brain are associated with certain types of visual information. For example, different regions are active when viewing a face or a crowd of people or a building. They believe as their understanding of these regions grow more sophisticated, they will better be able to pin point from fMRI scans what a subject has seen. Currently, they are able to get a rough idea of what a subject is looking at and then pull a corresponding image from a vast database of images. It's not quite a reconstruction yet, but it is close and will improve with further research.

An article from Wired notes that full visual reconstruction is still decades away, but could have implications for devices that read dreams or machines controlled through thought. However, as fMRI technology is so often used now in court cases (arguably prematurely given the current technology), it seems likely that one of the first applications we could see from this technology will be in justice system.

[Wired]

The report, published by Alzheimer's Disease International, is based on research carried out by a team led by Professor Martin Prince from the Institute of Psychiatry at King's College London. It predicts that 35 million people will suffer from dementia by 2010, but that that figure will rise to 65.7 million by 2030, and then to upwards of 115 million by 2050, and calls upon the World Health Organization to make dementia a priority for research, in the hopes of lessening pressure on sufferers and caregivers, according to Marc Wortmann, ADI's executive director:

The crisis of dementia and Alzheimer's can no longer be ignored. Unchecked Alzheimer's will impose enormous burdens on individuals, families, healthcare infrastructures and the global economy... There is hope yet, if action is taken now to fund improvements in dementia care services, and to increase investment in research.

Dementia cases to double in next 20 years, say researchers [Guardian.co.uk]

Psychologists at the University of California in Santa Barbara and the University of British Columbia have been studying the effects of reading on cognitive functions. They had one group of subject read Franz Kafka's short story "The Country Doctor," a strange and surreal tale, and had a second group read the same story, but structured in a way that made more traditionally logical sense to readers. After reading the story, the subjects were then given a grammar learning test in which they were asked to identify patterns within strings of letters.

Subjects who read the original Kafka story identified more letter strings than those who read the more logically structured version, and were actually more accurate in their identifications, suggesting that they had better learned the patterns. The researchers believe that, in reading a story without a readily identifiable logic or structure, the subjects' brains began actively looking for patterns:

"You get the same pattern of effects whether you're reading Kafka or experiencing a breakdown in your sense of identity," [study co-author Travis] Proulx said. "People feel uncomfortable when their expected associations are violated, and that creates an unconscious desire to make sense of their surroundings. That feeling of discomfort may come from a surreal story, or from contemplating their own contradictory behaviours, but either way, they want to get rid of it. So they're motivated to learn new patterns."

The rub, though, is that the surreal experience must be unexpected to get the desired cognitive boost. Going in knowing you are going to read a strange and surreal story might not have the same effect.

Reading Kafka 'enhances cognitive mechanisms', claims study [Guardian]

[University of California, Davis, neuroscientists] Deborah Hannula and Charan Ranganath first trained volunteers by showing them images of faces paired with background scenes. Then they ran tests in which the volunteers were shown one of the scenes, to cue their memories, followed by the same scene superimposed with three previously learned faces.

The volunteers correctly identified the face previously paired with the scene nearly two thirds of the time. But careful analysis of the volunteers' eye movements, combined with measurements of brain activity using functional magnetic resonance imaging, revealed that the hippocampus was often retrieving memories even if these recollections didn't make it to the level of consciousness.

Somehow the hippocampus is able to retreive memories without that acitivity making it into your conscious mind. This work suggests a number of future areas of research. First of all, could we figure out a way to make the activity of the hippocampus touch the conscious mind, and improve our memories? And second, is it possible that we're acting on unconscious memories all the time, letting them color our decisions and calling them "intuition" or "just a feeling"?

This research is forthcoming in Neuron.

In a paper published in this month's Neuroscience, philosopher Adam Shriver suggested that genetically engineering cows to feel no pain could be an acceptable alternative to eliminating factory farming. And some neuroscientists are on their way to making Shriver's suggestion a very real possibility. Zhou-Feng Chen, a neuroscientist at Washington University, has been working on identifying the genes that "affective" pain, the unpleasantness associated with painful sensations. Chen and his team have identified a gene called P311, and have found that mice who lack P311 do not have negative associations with pain, although they do react negatively to heat and pressure. Chen believes that, with the removal of the same P311 gene, livestock like pigs and cows could be engineered to feel no pain.

So what are the ethicists saying? Peter Singer, the famed bioethicist and author of Animal Liberation, has often advocated vegetarianism and veganism to avoid animal suffering, but says if livestock could be bred to feel no pain, he would not take issue with the cruelty aspect of factory farming. However Singer, and other ethicists note that, even with pain-free meat, the environmental impact of factory farming cannot be ignored.

Pain-free animals could take suffering out of farming [New Scientist]

Apparently when this woman had seizures, she felt that her voice had become deeper and her arms were hairy. Once, when a female friend of hers with her as a seizure came on, she thought her friend was turning into a man too. The woman had no history of mental illness, nor did she have symptoms of gender identity disorder.

After imaging her brain, the researchers discovered that she had some damage to her amygdala, and weird electrical activity in her right temporal lobe during seizures. Had they discovered some gender identity center of the brain, which when damaged results in the feeling of changing sex? Absolutely not. In fact, there is no such center in the brain.

Instead, the researchers believe that this unusual case is simply one flavor of a more general experience of self-alienation that comes during epileptic attacks.

Reports ScienceNow:

More likely, [New York University neurologist Orrin Devinsky] says, the amygdala is one node in a network of brain regions essential for self-identity. When neural activity in this network goes haywire, a range of bizarre experiences can result, Devinsky says. The Russian novelist Fyodor Dostoyevsky wrote of feeling the presence of God in the moments preceding a seizure. More common, Devinsky says, are feelings of déjà vu or its opposite, jamais vu, the sense that a familiar environment has become unfamiliar. "In epilepsy, you can experience these intense and extreme emotions and in some cases misidentification of yourself and where you are in relation in the world," he says.

via Science Now

Specifically, dopamine is responsible for making you remember frightening experiences in the long term, rather than forgetting them right away.

Researchers studied the effect of dopamine on rats who had been terrified by having their paws electrically shocked. What the scientists discovered was that dopamine had no affect on the rats' memories if it was given shortly after the shock. But if the rats were given chemicals that reduced the amount of dopamine absorbed by their neurons about 12 hours later - roughly the time it takes for the brain to consolidate long-term memories - they forgot the painful experience quickly and walked right onto the foot-shocking device again. However, rats who received chemicals 12 hours later that enhanced the amount of dopamine absorbed remembered the foot-shocking device far longer than they might have otherwise. Their fear of foot shock remained quite vivid.

Let this be a lesson to all authoritarian regimes who want to rule with fear and drugs. Feed your population with dopamine promoters 12 hours after the public executions. Their terror and awe will last a lot longer, and you'll get a bigger bang for each buck you pay your death squads.

via Science

A team led by Lawrence Livermore Lab scientists Nipun Misraa and Julio A. Martinez worked on the discovery, and their results were published earlier this week in PNAS. According to a release about the research:

[The researchers] created a biomechanical hybrid in which nanowires are coated in a lipid bilayer-the same type of membrane that envelopes cells and controls the passage of molecules in and out of the cell. The authors incorporated gated channels in this membrane, and used molecular transport through these channels to trigger an electric signal. The researchers show that the nanowire circuit can be used to make the channels open and close as they would in a biological cell. Although their work is currently in an early stage, later versions of the nanowire technology could find applications in biosensing, neuroscience, and medicine.

There are two things that are very exciting about this early-stage research. One, it means that cellular membranes could be incorporated into computerized devices that are designed to respond to molecules in the environment. Essentially, you could have a cellular sensor at the end of a nanowire.

But the applications for neuroscience and medicine are even greater. The membrane that these researchers have learned to manipulate is part of the same system that controls cell-to-cell communication in the human body. Proteins that arrange themselves on the surface of cells serve as signal transducer, conveying information between genetic material inside each cell to proteins or chemicals in the blood (and vice versa). For example, when a cell malfunctions, it usually sends out a signal asking to be destroyed by the cells around it. In cancer and AIDS, however, this signal is interrupted so that the diseased cells continue to thrive and infect more of the body. Being able to control those cellular signals with nanowires could potentially help contain some cancers.

It would also open up a very weird area of medicine whose consequences we can't know for certain. What would it mean if you could control cellular signals, sending very precise messages to cells or cell groups? Obviously it would be great for controlling healing, but could it also be a method of physical enhancement? A way to lose weight by telling fat cells to die? It's possible.

via PNAS

Reuters' FaithWorld blog has been covering the University of Pennsylvania's Neuroscience Boot Camp, going on now, and one message has become clear:

You can forget about the "God spot" that headline writers love to highlight (as in "‘God spot' is found in Brain" or "Scientists Locate ‘God Spot' in Human Brain"). There is no one place in the brain responsible for religion, just as there is no single location in the brain for love or language or identity. Most popular articles these days actually say that, but the headline writers continue to speak of a single spot.

"There isn't a separate religious area of the brain, from what we can tell from the data," said Dr. Andrew Newberg, an associate professor of radiology and psychiatry at the Penn university hospital and author of several books on neuroscience and religion. "It's not like there's a little spiritual spot that lights up every time somebody thinks of God. When you look at religious and spiritual experiences, they are incredibly rich and diverse. Sometimes people find them on the emotional level, sometimes on an ideological level, sometimes they perceive a oneness, sometimes they perceive a person. It depends a lot on what the actual experience is."

The image above shows two different brain scans, one from someone who is singing, and the other one from someone who is speaking in tongues. They look almost entirely identical, but you can just about glimpse a slight difference in blood flow to the frontal lobe, and specifically to the left caudate, among the "speaking in tongues" brains. (Thanks to The NeuroCritic for the image, and for pointing out that the study's authors admit their "results were hypothesis driven.")

The FaithBlog quotes neurological researcher Geoff Aguirre as pouring cold water on the idea that an fMRI scanner is like a mind reader, and calls the idea that you could use an fMRI to catch terrorists "science fiction, science fantasy." Adds Aguirre:

There's definitely an esthetic in the presentation of this data. People see this as a natural aspect of the brain, not the result of tests. Some groups made a very wise investment in the display technology for how neuroimaging results were reported. Those were the images that got displayed on the covers of the top scientific journals and made a splash.

I also love his comments about "Cartesian dualism," in which people try to claim that someone's actions weren't his fault because "his brain did that." (As if he and his brain are two separate beings.)

[Reuters and The NeuroCritic]

Neuroscientists have discovered that the amygdala - the part of the brain that senses fear and emotion - kicks into gear when people listen to scary music with their eyes shut. To prove this theory, volunteers in a study held at Tel Aviv Sourasky Medical Center in Israel were monitored while listening to pieces of music both with and without the benefit of visual stimulus. While more neutral music produced the same responses from those with eyes opened and closed, more unsettling music produced more neurotransmitter noradrenalin in subjects with closed eyes than open, as if responding to a threat. Talma Hendler, who ran the study, isn't surprised by the results:

A lot of time we do like to close our eyes when we listen to music, we feel like this is a more powerful experience... I suspect if we had music that was positive, we would get a similar effect.

Now all we need to do is fund a similar study on what happens to those who listen to Stan Bush's "The Touch."

Scary music is spookier with eyes shut [New Scientist]

About the study, New Scientist writes:

The researchers do, however, have suspicions about what the active chemical might be. The steroid androstadienone is the primary suspect, and [lead researcher Lilianne] Mujica-Parodi's team say it plans to synthesise it.

"I'm not naïve about the fact that some people will look at this study and say it was irresponsible," says Mujica-Parodi. There are obvious ethical issues about synthesising a chemical that could induce fear in other people, and the group's early research was funded by the US military.

I'm glad Mujica-Parodi isn't naive about what other people will think. But isn't she being a little naive about what other people will do with this stuff if she successfully recreates it?

via New Scientist

The Swiss scientists used a technology developed to kill uterine fibroids without surgery that an Israeli company modified for use in the brain, according to the MIT Technology Review. That company, Insightec, combined the high-intensity focused ultrasound technology used on the fribroids with CT scans and MRIs to allow doctors to focus on the part of the brain they wish to excise and see the results in real time. Eyal Zadicario, head of InSightec's neurology program, said:

You take a CT scan of the patient's head and tailor the acoustic beam to focus through the skull.

Technology Review elaborates:

The device also has a built-in cooling system to prevent the skull from overheating.

The ultrasound beams are focused on a specific point in the brain—the exact location depends on the condition being treated—that absorbs the energy and converts it to heat. This raises the temperature to about 130 degrees Fahrenheit and kills the cells in a region approximately 10 cubic millimeters in volume.

In effect, the high-intensity focused ultrasound cauterizes a specific, internal section of the brain, destroying the tissue completely.

The nine patients in the Swiss study suffered from chronic pain that couldn't be treated with medications; the ultrasound surgery successfully destroyed a small area of their thalamus, bringing relief from the pain without other, significant side effects. They hope to start testing the machine on Parkinson's patients, in an effort to bring them relief from some of the the physical side effects of that disease.

Brain Surgery Using Sound Waves [MIT Technology Review via Live Science]

So what has hip-hop done to incur the wrath of pediatric neurosurgeons? It gave the world car surfing, which involves one or more persons treating the head of a moving car as a surfboard. The paper points the finger at the Bay Area's Hyphy movement, in particular, for glamorizing an activity that tends to end in severe head trauma.

The study's authors don't lay exclusive blame on Hyphy, noting that the car-surfing meme (along with head injuries) spikes with each release of Grand Theft Auto, each YouTube video, and every incident of car surfing on the silver screen (Teen Wolf gets a mention, but Zoe Bell's nail-biting Death Proof stunt is conspicuously absent). But, unless they can travel back in time and kill the Hyphy movement's grandparents, it seems that these neurologists are stuck with the ages-old problem of keeping kids from doing stupid things.

Neurological injuries from car surfing [Journal of Neurosurgery]

While some people already think that brain-imaging lie detectors are a scam, others remain convinced that they're the wave of the future. A recent study by Joshua Greene and Joseph Paxton at Harvard University shows that the skeptics might be right.

Paxton and Greene bet their subjects money based on guessing a coin flip. While those who had to record their responses in advance had average success, those who didn't have to tell their guess until after they knew the result had a high success rate, indicating they were lying. More interestingly, those people who were even interested in lying showed brain activity when just offered the opportunity to cheat, while those who were more honest showed no difference in their brain activity regardless of the opportunity to cheat. Over time, Greene and Paxton were able to predict whether certain volunteers would lie at all. They expect that their machine could be developed not just to determine whether someone was lying or had lied, but if they were interested in doing so or would in the future.

You always knew your brain would eventually betray you. The question is, how useful is this information really? Doesn't everyone want to lie sometimes, including people who are honest?

Truthfulness Requires No Act of Will for Honest People [via Harvard]

[Image via the Arnold School of Public Health]

Philosopher Dan Lloyd uses functional MRIs — which track changes in brain activity by lighting up in different colors and intensities as the brain processes information — to create music, by assigning each area of the brain a note and each level of intensity a volume. A computer does the rest, analyzing the movements of the functional MRIs and creating musical pieces that correspond to the changes.

In the course of his work, Lloyd discovered that scans of patients with dementia and schizophrenia make audibly different music than those of people with normal brains: people with dementia have more erratic rhythms and less bright notes, while people with schizophrenia have more complex patterns in the music created by their brains.

Besides making their way onto the iPods of Lloyd's students, scientists think the application could allow them to better distinguish abnormalities in brain scans. According to New Scientist:

His colleague Didier Grandjean at the University of Geneva in Switzerland says that brain music might help identify temporal patterns in particular. "Melodies are a much better way to build complex mental representations over time than anything the eye can do," he says.

Of course, that's only if one takes the time to pay attention to the music that's being made, as opposed to how we think it ought to sound.

Eavesdropping On The Music Of The Brain [New Scientist]

Related: D.O.A. (Death of Auto-Tune) [YouTube]

[Image via the Centre for Educational Neuroscience]