Tag Archives: brain imaging

c. elegans nematode brain activity

What a worm’s brain looks like fired up

These aren’t Christmas lights, but the actual neural activity of Caenorhabditis Elegans, a parasitic nematode. The brain imaging was done by researchers at Princeton University, and no worm had to be cut open. Instead, the researchers used a special protein which  fluoresces in response to calcium.

c. elegans nematode brain activity

When scientists tap the brain, they’re looking for one prime indicator: electrical activity. When a neuron is active, it fires an action potential which is basically a depolarization made between a neuron’s axon to another neuron it signals to. Now, traditionally neuroscientists use a technique called electrophysiology to study the patterns of neuron electrical activity. It’s precise, yet the analysis is limited to a handful of neurons at a time. A more interesting method exploits the fact that when a neuron is active (again, depolarized), calcium flows into it. Using special dyes (proteins) that fluoresce in response to whether or not they bind to calcium, scientists can monitor these calcium dynamics and in turn the depolarization.

That’s exactly what the Princeton researchers achieved, allowing them to monitor in real time  77 of the nematode’s 302 neurons as they light up. These have been shared in this amazing video, split into four frames. In the upper left, we see the location of the neurons, while the upper right shows a simulation of the calcium signaling which is analogous to neural electrical patterns. In the lower two panels we zoom out: the worm itself (left) and the location of the brain (right).

Using this data, the researchers would like to devise a mathematical model that will allow them to simulate and control the worm’s brain. Previously, other efforts identified how C. elegans can identify magnetic fields, while a more ambitious team from Harvard  targeted laser pulses at the worm’s neurons, and directed it to move in any directions they wanted,  even tricking the worm in thinking there’s food nearby.

Brain fMRI study predicts efficiency of anti-smoking Ads

Using functional magnetic resonance imaging, scientists from the universities of Michigan and Pennsylvania scanned the brains of 50 smokers while they viewed anti-smoking ads. They recorded their neural activity spikes as they watched the sample of 40 images one at a time, looking for increase activity in the medial prefrontal cortex, the area that handles decision making processes.

The paper, titled “Functional brain imaging predicts public health campaign success,” is published in the journal Cognitive and Affective Neuroscience.

Then the images were sent via e-mail to New York smokers in a campaign named “Stop smoking. Start living,” with a link embedded under the ads to sources with help on quitting smoking. The team believed that the ads which stimulated the MPFC the most during the Michigan fMRI study would achieve the best results in the campaign, which they estimated by the number of clicks each ad would receive.

The researchers predicted the ads which showed the most brain activity in the MPFC area would achieve the best results in e-mail campaigns.

And indeed, during the test campaign, Michigan trial data correlated well with the results: ads that caused intense spikes in activity achieved the highest Click-Through Rate — with only opened e-mails counted, CTR ranged from 10 percent for the least successful images to 26 percent for the ones that caused the most significant spikes.

This means that, just by looking at brain activity, researchers were able to predict which images were the best suited for the ad campaign. Emily Falk, a professor at Pennsylvania’s Annenberg School for Communication, commented:

“If you ask people what they plan to do or how they feel about a message, you get one set of answers. Often the brain gives a different set of answers, which may help make public health campaigns more successful. My hope is that moving forward, we might be able to use what we learned from this study and from other studies to design messages that are going to help people quit smoking and make them healthier and happier in the long run.”

Most of the successful images used a negative tone, contradicting research which shows that negative messages que the participant to take a more defensive approach to the message.

 

 

 

Einstein's brain, photographed in 1955, is about 15% wider than that of most people and, rather than being egg-shaped, it's almost perfectly round.

Einstein’s brilliance might have been due to strong brain hemisphere connection

Einstein's brain was preserved after his death in 1955, but this fact was not revealed until 1986.

Einstein’s brain was preserved after his death in 1955, but this fact was not revealed until 1986.

Mere hours after his death in 1955, Albert Einstein‘s brain was removed, weighed and analyzed in a lab at Princeton Hospital by pathologist Thomas Stoltz Harvey. Bits of his brains were then sent to other pathologists around the country for analysis in hope that a connection between its physical attributes and the remarkable genius of Albert Einstein might be discovered. A large portion of these brain section were actually kept by Harvey himself for his personal use, until these were re-discovered in the 1980’s sparking a heated controversy. Nevertheless, several anomalies or differences from the typical brain were identified. A newly devised technique that measures the large bundle of nerve fibers that connects the two hemispheres of the brain may suggest another Einstein’s brain anomaly. Apparently, Einstein’s left and right hemispheres were particularly well connected, which may have aided his intellectual abilities.

Despite his best efforts, Harvey’s preservation technique wasn’t the finest. Most assumptions and hypotheses regarding Einstein’s brain are based on the myriad of photographs the pathologist took from multiple angles. For instance, some photographs showed Einstein’s brain was missing a part of a bordering region called the lateral sulcus (Sylvian fissure). “This unusual brain anatomy…[missing part of the Sylvian fissure]… may explain why Einstein thought the way he did,” said Professor Sandra Witelson who led the research published in The Lancet. Professor Laurie Hall of Cambridge University commenting on the study, said, “To say there is a definite link is one bridge too far, at the moment. So far the case isn’t proven. But magnetic resonance and other new technologies are allowing us to start to probe those very questions.”

Einstein's brain, photographed in 1955, is about 15% wider than that of most people and, rather than being egg-shaped, it's almost perfectly round.

Einstein’s brain, photographed in 1955, is about 15% wider than that of most people and, rather than being egg-shaped, it’s almost perfectly round.

Weiwei Men of East China Normal University used a novel technique to image the corpus callosum – large bundle of fibers that connects the two cerebral hemispheres and facilitates interhemispheric communication in the brain. Men thus came up with a high-resolution that measures and color-codes the varying thicknesses of subdivisions of the corpus callosum along its length. The thicker these fibers are, the more the nerves that cross these suggesting a stronger connection between the two hemispheres.

[NOW READ] Albert Einstein’s secret to learning anything

Einstein’s callosum was compared to two sample groups:  15 elderly me and 52 men Einstein’s age (26) in 1905 or his Annus Mirabilis (Miracle Year) when he published four ground-breaking papers that changed the world’s views about space, time, mass and energy. The findings show that  Einstein had more extensive connections between certain parts of his cerebral hemispheres compared to both younger and older control groups.

“This study, more than any other to date, really gets at the ‘inside’ of Einstein’s brain,” said lorida State University evolutionary anthropologist Dean Falk, who was also part of the study. “It provides new information that helps make sense of what is known about the surface of Einstein’s brain.”

The study was published in the journal Brain.

Tiny neuromicroscope can see inside a moving animal’s brain

A team of neuroscientists from Stanford University have managed to create a remarkably tiny device capable of monitoring brain activity in a rodent or other small animals. The device can be manufactured extremely cost-effective and might prove to be an invaluable tool for researchers of the new decade.

A fluorescence microscope of tiny proportions - it weights only 2 grams! Credit: Dan Stober, Stanford News Service

A fluorescence microscope of tiny proportions - it weights only 2 grams! Credit: Dan Stober, Stanford News Service

Mice have always been the lab subjects of choice, and besides running around mazes for cheesy treats, rodents have now a new reason to rejoice. I mean, what mouse wouldn’t love one of these beauts wrapped around its head? The tiny microscope, weighing only 2 grams, is capable of monitoring up to 200 individual brain cells as the subjects moves around its environment. That’s actually more than a very expensive lab-sized equipment can rend, which requires the subject not to move.

The device, in principle, works by detecting fluorescent light, often used in biological research to mark different cells. Due to its tiny size and weight it can be easily strapped on a mouse’s head and used to accurately determine its brain pattern. Mice could be drugged and thus researchers will be able to see at a cerebral level how it interacts with the subject, or better understand what regions of the brain are more active when a subject is performing a particular task. Applications are numerous.

The cost? Well, the development cost for the prototype is figured at $50,000, however future models could drop in price extremely. First of all, all its components are already mass-produced everywhere on the mobile market, especially its core component, a complementary metal-oxide-semiconductor (CMOS) sensor, which can be found in most modern cell phone’s camera.

“The massive volume of the cell-phone market is driving costs down while not sacrificing performance,” says Aydogan Ozcan, professor of electrical and biomedical engineering at the University of California, Los Angeles. “Scientists are realizing that with cost-effective compact architecture, they can have components that a decade ago would cost thousands of dollars, if you could find them.”

The team of researchers, lead by Mark Schnitzer, a neuroscientist at Stanford University, got the idea to create this device after they understood they need to manufacture their own microscope to study how the brain directs movement. In the process, they managed to create a highly feasible and lucrative device, which quite possible might become highly commercial appealling in the future. Schnitzer and colleagues have already established a small start-up with this in mind.

“The advancement in being able to make a fluorescent scope this compact is really significant,” says Daniel Fletcher, a bioengineer at the University of California, Berkeley, who was not involved in the research. “For the animal to be able to carry the whole microscope along with it opens a lot more possibilities in studying behavior.

The study was published in this week’s issue of Nature Methods.
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