Tag Archives: mri

Machine learning tool 99% accurate at spotting early signs of Alzheimer’s in the lab

Researchers at the Kaunas Universities in Lithuania have developed an algorithm that can predict the risk of someone developing Alzheimer’s disease from brain images with over 99% accuracy.

Image credits Nevit Dilmen via Wikimedia.

Alzheimer’s is the world’s leading cause of dementia, according to the World Health Organization, causing or contributing to an estimated 70% of cases. As living standards improve and the average age of global populations increase, it is very likely that the number of dementia cases will increase greatly in the future, as the condition is highly correlated with age.

However, since the early stages of dementia have almost no clear, accepted symptoms, the condition is almost always identified in its latter stages, where intervention options are limited. The team from Kaunas hopes that their work will help protect people from dementia by allowing doctors to identify those at risk much earlier.

Finding our early

“Medical professionals all over the world attempt to raise awareness of an early Alzheimer’s diagnosis, which provides the affected with a better chance of benefiting from treatment. This was one of the most important issues for choosing a topic for Modupe Odusami, a Ph.D. student from Nigeria,” says Rytis Maskeliūnas, a researcher at the Department of Multimedia Engineering, Faculty of Informatics, Kaunas University of Technology (KTU), Odusami’s Ph.D. supervisor.

One possible early sign of Alzheimer’s is mild cognitive impairment (MCI), a middle ground between the decline we could reasonably expect to see naturally as we age, and dementia. Previous research has shown that functional magnetic resonance imaging (fMRI) can identify areas of the brain where MCI is ongoing, although not all cases can be detected in this way. At the same time, finding physical features associated with MCI in the brain doesn’t necessarily prove illness, but is more of a strong indicator that something is not working well.

While possible to detect early-onset Alzheimer’s this way, however, the authors explain that manually identifying MCI in these images is extremely time-consuming and requires highly specific knowledge, meaning any implementation would be prohibitively expensive and could only handle a tiny amount of cases.

“Modern signal processing allows delegating the image processing to the machine, which can complete it faster and accurately enough. Of course, we don’t dare to suggest that a medical professional should ever rely on any algorithm one-hundred-percent. Think of a machine as a robot capable of doing the most tedious task of sorting the data and searching for features. In this scenario, after the computer algorithm selects potentially affected cases, the specialist can look into them more closely, and at the end, everybody benefits as the diagnosis and the treatment reaches the patient much faster,” says Maskeliūnas, who supervised the team working on the model.

The model was trained on fMRI images from 138 subjects from The Alzheimer’s Disease Neuroimaging Initiative fMRI dataset. It was asked to separate these images into six categories, ranging across the spectrum from healthy through to full-onset Alzheimer’s. Several tens of thousands of images were selected for training and validation purposes. The authors report that it was able to correctly identify MCI features in this dataset, achieving accuracies between 99.95% and 99.99% for different subsets of the data.

While this is not the first automated system meant to identify early onset of Alzheimer’s from this type of data, the accuracy of this system is nothing short of impressive. The team cautions that “such high numbers are not indicators of true real-life performance”, but the results are still encouraging, and they are working to improve their algorithm with more data.

Their end goal is to turn this algorithm into a portable, easy-to-use software — perhaps even an app.

“Technologies can make medicine more accessible and cheaper. Although they will never (or at least not soon) truly replace the medical professional, technologies can encourage seeking timely diagnosis and help,” says Maskeliūnas.

The paper “Analysis of Features of Alzheimer’s Disease: Detection of Early Stage from Functional Brain Changes in Magnetic Resonance Images Using a Finetuned ResNet18 Network” has been published in the journal Diagnostics.

After scanning canine brains: “Dogs are people, too,” says neuroscientist

Credit: Pixabay.

Most dog owners will tell you that their pets are awesome. They love their dogs, and their dogs seem to love them back. But do dogs genuinely feel love or any kind of positive emotion similar to how a human does for that matter? This is a question that has eluded scientists for a long time.

It’s easy to put a dog’s tremendous enthusiasm whenever their owner comes home as just as a form of attachment, viewing the human as a walking, breathing food dispenser and nothing more.

But a breakthrough research might change the way people view dogs forever. According to neuroscientist Gregory Berns,  “dogs are people, too.”

He reached this conclusion after performing MRI scans on over a dozen dogs, finding the same brain region responsible for positive emotions in humans is activated in dogs as well.

[Also Read: Do dogs dream?]

To infer animal sentience and other neurological traits, scientists rely on animal behaviorism. You can’t ask a dog how it feels, or what it’s thinking. As such, it’s been considered an extremely challenging area of research. By using brain scans, however, one can bypass having to directly ‘speak’ to an animal. Instead, you let the brain do all the talking.

But this doesn’t mean performing MRI on animals is straightforward. The machines are racketing, claustrophobic, and generally unpleasant even for humans. For them to work you have to stay completely still. You can imagine how difficult it is to get a hyper labrador to stay put while all kinds of machinery are diverting its attention. Typically, veterinarians perform anesthesia on dogs whose brain scans they need to perform, but this renders any kind of emotion monitoring useless.

Dog emotions, not too different from ours

Berns tackled this issue by training dogs using painstaking reward exercises to stay still when inside the operating MRI, and in doing so he has performed the first wake dog MRIs, as reported in PLOS ONE. Inside the scanner, the dogs’ brain activity was measured for a two-hand signal (which they learned to associate with food), as well as for scents of familiar and unfamiliar dogs and humans.

Both the human and dog brains are strikingly similar in function and structure in one key region: the caudate nucleus. Located between the brainstem and the cortex, the dopamine-rich caudate plays a key role in the anticipation of things we enjoy, like food, love, and money — things that are associated with positive emotions.

“Many of the same things that activate the human caudate [part of the brain], which are associated with positive emotions, also activate the dog caudate. Neuroscientists call this a functional homology, and it may be an indication of canine emotions,” Berns wrote in an article for the NY Times.

Berns with one of the dogs from his research. Credit: Gregory Berns.

In response to hand signals indicating food, as well as smells of familiar humans, the canine caudate activity increased. And in preliminary tests, it activated to the return of an owner who had momentarily stepped out of view. Neuroscientists call this a functional homology, and it may be an indication of canine emotions.

“The ability to experience positive emotions, like love and attachment, would mean that dogs have a level of sentience comparable to that of a human child. And this ability suggests a rethinking of how we treat dogs,” Berns said.

“DOGS have long been considered property. Though the Animal Welfare Act of 1966 and state laws raised the bar for the treatment of animals, they solidified the view that animals are things — objects that can be disposed of as long as reasonable care is taken to minimize their suffering.”

“But now, by using the M.R.I. to push away the limitations of behaviorism, we can no longer hide from the evidence. Dogs, and probably many other animals (especially our closest primate relatives), seem to have emotions just like us. And this means we must reconsider their treatment as property.”

So, do dogs truly love us? We can’t be sure, but next time you see your dog wag his tail you can be sure he’s happy, scientific proof included.

[NOW READ] Study proves humans can read a dog’s emotions just by looking at its face

Gregory Berns is a professor of neuroeconomics at Emory University and the author of “How Dogs Love Us: A Neuroscientist and His Adopted Dog Decode the Canine Brain.”

First MRI mapping of a squid’s brain reveals surprising complexity

New research at The University of Queensland (UQ) is peering into the neurology of squids, creating the first MRI model of their brains.

Arguably one of the best pictures you’ll see all day.
Image credits Wen-Sung Chung, Nyoman D. Kurniawan, N. Justin Marshall, (2020), iScience.

The research can help us understand how the squid’s abilities — their incredible camouflage for example — are handled by their central nervous system.

Brainy beasts

“Some cephalopods have more than 500 million neurons, compared to 200 million for a rat and 20,000 for a normal mollusc,” says Dr Wen-Sung Chung from UQ’s Queensland Brain Institute, first author of the study.

“This the first time modern technology has been used to explore the brain of this amazing animal.”

Cephalopods — a group whose name means “head foot” and includes cuttlefish, squid, and octopi — are intelligent animals with complex brains. We’ve been studying their brains for almost 50 years now, trying to map out all their neural connections, in order to understand how they work.

And work they do: cephalopods exhibit several complex behaviors, with their active camouflage being arguably the most famous. It’s even more impressive when you consider that cephalopods themselves are colorblind. They can also solve problems, count, recognize patterns, and communicate through various signaling processes.

The squid’s (Sepioteuthis lessoniana) multi-lobed brain.
Image credits Wen-Sung Chung, Nyoman D. Kurniawan, N. Justin Marshall, (2020), iScience.

We do know that cephalopod brains have evolved to have different subdivisions, and we do have a rough understanding of how they connect together. The team’s work focuses on understanding why this division emerged. They worked with the reef squid Sepioteuthis lessoniana, using techniques such as MRI to study and map the architecture of their brains. They report finding 145 new potential connections and pathways, more than 60% of which are linked to the squid’s vision and motor systems.

“We can see that a lot of neural circuits are dedicated to camouflage and visual communication. Giving the squid a unique ability to evade predators, hunt, and conspecific communicate with dynamic colour changes,” Dr Chung explains.

Dr Chung says that the present findings support a convergent evolution — the independent evolution of similar traits — between the nervous systems of cephalopods and that of vertebrates. These similarities, he adds, should allow us to make informed predictions about how the squid’s brain structure translates on the behavioral level. For example, the team considered that several of the new networks they found deal with locomotion and countershading camouflage (both abilities that rely on sight) based on their similarities to vertebrate brain networks.

“Our findings will hopefully provide evidence to help us understand why these fascinating creatures display such diverse behaviour and very different interactions,” the authors conclude.

The paper “Toward an MRI-Based Mesoscale Connectome of the Squid Brain” has been published in the journal iScience.

What’s an MRI and how does it work?

Magnetic resonance imaging (MRI) is a medical technique that can capture images from inside the living body by using powerful magnets and radio waves. Nowadays, MRIs are routinely used to examine internal body structures and diagnose diseases without having to cut anything open.

Credit: Wikimedia Commons.

The first MRI scanner for the human body was invented in 1977. Since then, the technology has proven revolutionary in medical practice and neuroscience.

The invention of X-ray imaging, which allows doctors to see bone fractures and dislocations, changed medicine forever. Later came ultrasound imaging, computed tomography (CT), and MRI. The latter came as a natural complementary technology, which allowed doctors to see the structure of cartilage, ligaments, muscles, joints, and other types of tissue that can’t be possibly shown by an X-ray.

How MRI works

MRI scan. Credit: Pixabay.

Unlike other imaging methods that employ radiation, MRIs rely on huge magnetic fields to scan living internal structures.

An MRI scanner is essentially a giant magnet. Most MRI scanners found in hospitals operate at 0.5 to 3 Tesla (the unit of measurement for magnetic field). For comparison, the planet’s magnetic field sits at around 0.00006 T — that’s 60,000 times weaker than a typical MRI’s magnetic field.

Generating a magnetic field of this magnitude entails quite the setup. Most MRI devices use a superconducting magnet which creates a magnetic field by passing electricity through many coils. Maintain a magnetic field up to 2 Tesla in strength requires a lot of energy, which is an MRI’s wires are bathed in liquid helium that cools them near absolute zero. At nearly minus 269°C, the wires achieve superconductivity, meaning electricity can flow through them with virtual no resistance.

In order to image the internal structure of biological entities, MRIs exploit the physical properties of water. The interaction between magnetic fields and radio waves generated by water (particularly its hydrogen atoms) can be used to map the location of water molecules.

Humans are about 65% made of water, so it’s fairly straightforward to generate images using this method.

Water molecules (H2O) are made of hydrogen protons and oxygen. And it’s the hydrogen atoms that are the most important part of the mechanism that enables MRI machines.

Like Earth, hydrogen protons spin on their own axis. Each spinning hydrogen proton is like a tiny magnet that spins around its own axis, a motion known as precession.

Our body contains billions of hydrogen protons all spinning differently on their axes in random positions.

However, when a person steps in an MRI machine, the very powerful magnetic field causes the hydrogen protons spinning axes to realign with the scanner’s magnetic field (also known as the B0 field). This is similar to how a compass needle aligns with Earth’s magnetic field.

Some of these protons will align “up” (parallel) and some will align “down” (anti-parallel). About half go each way, so the magnetic fields cancel each other. But due to quantum mechanical effects, there are slightly more “up” protons, only about a couple out of every million. Although that may not sound like a lot, the sheer number of hydrogen atoms found in the human body means there are enough unmatched protons to create a very detailed image.

At this stage of the scanning, the MRI machine fires a radio frequency pulse towards the area of the body that needs to be examined. The pulse is tuned such that only the hydrogen protons respond, causing the unmatched protons to absorb the energy and spin in a different direction — this is the resonance part of MRI.

During the same time, three additional magnets, known as gradient magnets, are switched on besides the main magnetic field. These additional magnets are turned on and off rapidly, affecting the local magnetic field. In each fraction of a second that the magnet is turned on, a “slice” of the area to be imaged is generated.

MR angiogram in congenital heart disease. Credit: Wikimedia Commons.

After the MRI’s magnetic field is switched off, the protons gradually return to their normal precession and release the energy absorbed from the radiofrequency pulse. The signal is picked up by the coils and sent to a computer which ultimately converts it into an image. Since different body tissues generate different radio signals, the MRI is able to distinguish various types of tissue.

In summary, the physical principles of MRI can be divided into three stages: magnetization, resonance, and relaxation.

Types of MRI

White matter connections obtained with MRI tractography. Credit: Wikimedia Commons.

There are many forms of MRI, but the two most common ones are functional MRI (fMRI) and diffusion MRI.

Diffusion MRI has only been around for no more than 20 years. This type of MRI imaging is based upon measuring the random Brownian motion of water molecules with a tissue. Certain diseases can restrict this diffusion, something that is particularly true for cancers. As such, this method can be a very effective diagnostic tool.

Functional MRI, or fMRI, doesn’t just provide structural imaging — it can also be used to visualize functional activity, in the brain. It works by measuring changes in blood flow to different areas of the brain. This is how scientists are able to determine which parts of the brain are responsible for certain functions, making fMRI an integral part of modern neuroscience research. It can also be used to assess damage from an injury or brain disease like Alzheimer’s.

What taking an MRI looks like

Before the procedure, a doctor will ask the patient to strip off all their jewelry, credit cards, phone, and anything with metal parts. Patients also have to answer questions about their medical history, especially if any surgery or operation took place that resulted in an implant.

During an MRI, a patient who requires an internal body scan will first lie on a movable table, which then slides into a doughnut-shaped opening of the machine.

Although the magnetic fields generated by an MRI are enormous, these pose no risks to human health. However, people undergoing an MRI might complain about loud sledgehammer-like noises that the machine produces during its operation.

Once the loud hammering noise starts, the person undergoing the MRI scan needs to lie perfectly still otherwise they might have to repeat the procedure all over again.

A typical MRI scan lasts 30 to 60 minutes. A certified radiologist will then look at the final images and report the results to your doctor.

The risks of using MRI

Credit: Wikimedia Commons.

MRI is considered one of the safest imaging procedures. Unlike X-ray machines or CT scanners, MRIs do not employ ionizing radiation. For this reason, for instance, MRI can be safely used to image a fetus during pregnancy or other vulnerable patients. A person will typically feel nothing out of the ordinary when undergoing a body scan (apart from the loud noise) and there are no known biological hazards for humans associated with the exposure to the strong magnetic field.

That being said, the procedure is not without any risks. An MRI generates a huge magnetic field — it’s basically a huge magnet. And we all know what’s attracted to magnets: metal.

In today’s age, many people have metal implants, from pacemakers to artificial joints and metal plates. These implants can heat up or move considerably inside a magnetic field. Fortunately, many implants performed today are designed to be MR-safe.

In any event, no metal objects should be inside the MRI room when the machine is turned on. Even a pen or paperclip can be turned into extremely dangerous projectiles that fly towards the opening of the magnet at very high velocity.

There’s also something to be said about the loud noise produced by the machine. Patients are always asked to wear ear protection when stepping inside an MRI.

Credit cards and anything with magnetic encoding will be erased, so that’s something to consider as well.

MRI study shows how Beatboxing really works — and it’s crazy

Beatboxing is an art form in which performers create percussive sounds using nothing but their vocal tract. Now, a team of scientists is using a real-time MRI machine to see how beatboxers create their magic.

Beatboxing techniques have been used as early as the 19th century, but true beatboxing is derived from the mimicry of early drum machines. Nowadays, beatboxing is mostly associated with hip-hop, though it is not limited to it.

Several studies have been carried out on beatboxers, but in the past, they’ve consisted of only one beatboxer with a particular native language. The new study looked at several beatboxers of different ages and genders and with different native languages.

The team used real-time MRI to observe the vocal tracts of beatboxers just before they make a sound to see how those movements differ from the movements associated with speech. Using real-time data offers a dynamic view of the entire vocal tract, at a high enough resolution to observe the movement and coordination of the different biological elements.

“Beatboxers may learn something different in preparing to make a sound than they do when they’re talking,” said Timothy Greer, a doctoral candidate at the University of Southern California. “Using real-time MRI allows us to investigate the difference in the production of music and language and to see how the mind parses these different modalities.”

Three different snare drum effects were demonstrated by the subject, each produced with different articulatory and airstream mechanisms. The technical names are: a click, an ejective affricate, and a pulmonic egressive dorsal stop-fricative sequence. Image credits: Timothy Greer.

The results surprised even Greer: beatboxers use movements not present in any known languages to produce a wide variety of sounds. Essentially, it’s a completely different way of moving the vocal tract.

“We found that beatboxers can create sounds that are not seen in any language. They have an acrobatic ability to put together all these different sounds,” said Greer. “They can hear a sound like a snare drum and they can figure out what they need to do with their mouth to recreate it.”

“As far as we know, some of the articulations that beatboxers can use are not attested in any language,” He added for ZME Science.

However, this type of study remains challenging, because existing algorithms to analyze the vocal tract movement are based on existing languages — and since beatboxing doesn’t seem to resemble any of them, different and new algorithms are needed.

“The vocal tract is amazing but it’s also incredibly complex. We need to keep creating better computer algorithms to understand how it all works together,” said Greer.

This is only the start, however — the group that acquired the data is already working on algorithms to analyze beatboxing is already working on ways to analyze and better understand this unusual form of art.

“The same group that collected the real-time MRI beatboxing videos–the Speech Production and kNowledge (SPAN) group at USC–has developed a set of region-of-interest (ROI) and segmentation algorithms that can be used on rtMRI data to determine how the different components of the vocal tract move in relation to each other. We are using these tools on our rtMRI data now to get more quantitative observations about beatboxing.”

However, this field of research is not only about beatboxing itself (though it will be a valuable resource for the community) — it can teach us a lot about speech patterns, and even shed some light on our vocal tract anatomy.

“This research has practical and theoretical benefits. Practically, this is one of the first looks at how the vocal tract moves during beatboxing; these videos offer the beatboxing community a tool to use in their art for teaching, exploration, and innovation. This work also benefits linguistic theory because it shows what the vocal tract can do when stretched to its limits. It addresses questions like “why do some sounds exist in speech, but not others?” and “which speech patterns exist only in language, and which speech patterns are grounded in broader cognitive capacities?”.”

Greer will present his findings at the Acoustical Society of America’s 176th Meeting.

Parents might soon watch their unborn babies grow up in 3D

Modern technology is impressive, extremely useful, and sometimes a bit disturbing. Thanks to a new development, parents might soon be able to see their unborn babies developing in realistic 3-D immersive visualizations.

3D virtual model MRI view of fetus at 26 weeks.
Credit: Image courtesy of Radiological Society of North America

Even if you’re not a parent you have to admit this is pretty cool. The new technology transforms MRI and ultrasound data into a 3-D virtual reality model of a fetus. Initially, sequential MRI slices are used as a scaffold for the model, and then the entire fetus baby is reconstructed in 3D. The accurate model includes the womb, umbilical cord, placenta and fetus, and researchers argue that the technology could even be used for educational purposes – not just for eager parents.

“The 3-D fetal models combined with virtual reality immersive technologies may improve our understanding of fetal anatomical characteristics and can be used for educational purposes and as a method for parents to visualize their unborn baby,” said study co-author Heron Werner Jr., M.D., Ph.D., from the Clínica de Diagnóstico por Imagem, in Rio de Janeiro, Brazil.

They key is the virtual reality which makes the visualization so spectacular. Dr. Werner and colleagues used the latest-generation Oculus Rift 2 headset. Oculus Rift is a virtual reality headset developed and manufactured by Oculus released earlier this year, one of the best virtual reality technologies available at the moment.

“The experience with the Oculus Rift has been wonderful,” Dr. Werner said. “It provides fetal images that are sharper and clearer than ultrasound and MR images viewed on a traditional display.”

But this is more than just a cool visualization technique, it could actually save lives. A big advantage is that it offers an assessment tool for fetal airway patency. Fetal airway patency is basically the way through which the unborn baby’s airways open and close, and this technology could highlight dangerous abnormalities. Researchers already report that the technology has proven useful in one case, where a baby suffered from an abnormality that required postnatal surgery. They hope to use this approach more broadly over the next year.

“The physicians can have access to an immersive experience on the clinical case that they are working on, having the whole internal structure of the fetus in 3-D in order to better visualize and share the morphological information,” Dr. Werner said. “We believe that these images will help facilitate a multidisciplinary discussion about some pathologies in addition to bringing a new experience for parents when following the development of their unborn child.”

Scientists quantify human intelligence for first time ever using MRI scans

Image credit Pixabay

Image credit Pixabay

Human intelligence is a tricky subject – many believe that the results of standard intelligence tests should be taken with a grain of salt due its various facets that are difficult to quantify, while others believe in using universal standards.

Now, for the first time ever, a team of researchers from the University of Warwick has defined and measured human intelligence using data from a study that quantifies the brain’s unique functions. The study identified the various parts of the brain, how they interact at different times, and how this information is related to intellect, revealing that variability in brain function is connected to higher levels of intelligence and creativity.

Using magnetic resonance imaging (MRI), the team behind the study examined resting-state brain scans from people all around the world and found that areas of the brain that are connected to intelligence show higher levels of variability compared to areas not associated with intelligence. In particular, the data showed that regions of the brain connected to intelligence experience frequent changes in their neural connections to other regions of the brain, with changes taking place in a matter of minutes or seconds.

“Human intelligence is a widely and hotly debated topic and only recently have advanced brain imaging techniques, such as those used in our current study, given us the opportunity to gain sufficient insights to resolve this and inform developments in artificial intelligence, as well as help establish the basis for understanding and diagnosis of debilitating human mental disorders such as schizophrenia and depression,” said Jianfeng Feng of the University of Warwick and senior author of the study.

In addition to presenting the possibility of better understanding human mental health, the data could also help us further advance artificial intelligence (AI) systems, which currently do not possess the level of variability and adaptability seen in the human brain. Further research could help us create AI systems with neural networks that can grow and adapt in a way that mirrors the human brain’s intelligence and learning capabilities.

Journal Reference: Neural, electrophysiological and anatomical basis of brain-network variability and its characteristic changes in mental disorders. 14 July 2016. 10.1093/brain/aww143

heart_metal_liquid

Heart injected with liquid metal imaged with unprecedented detail

Imaging the fine and intricate structures of blood vessels in the human body is paramount to modern anatomy. By knowing the body in greater detail, scientists are able to devise better treatments. Conventional imaging, however, is limited in how far it can peer through blood vessels. This may be set to change for the better after Chinese researchers have found an unconventional way to X-ray image blood vessels with unprecedented detail: filling the blood with liquid metal.

[ALSO READ] Scientists engineer heart that beats on its own 

A heart of metal

Typically, blood vessels are imaged by means of X-ray tomography, which produces strikingly beautiful 3D pictures of the heart hard at work. For it to work nicely, the X-rays need to be absorbed more aggressively, so a contrast agent that  absorbs X-rays more than the surrounding tissue is pumped in the heart. Usually, this contrast agent is iodine, which has a high electron density. Some other fluids, denser (these produce the most effective tomography) or otherwise, are also being used. Seems like everybody’s been missing the obvious, though: using a metal.

Researchers at Tsinghua University in Beijing  used gallium as a contrast agent – a metal which melts at about 29 degrees centigrade and so is liquid at body temperature.  What makes it perfect for the job, however, is that it’s chemical stable and doesn’t react with water. This way it flows easily even through the thinnest blood vessels. 

The image below shows two pig hearts, one injected with liquid gallium (left) and the other with a standard iodine-based contrast agent. The differences are striking – even capillaries with a diameter of only 0.07 millimetres can be seen. The researchers boast that using higher resolution techniques, even smaller blood vessels can be imaged. 

heart_metal_liquid

Image: Quantitative Biology

“The capillaries that used to be hardly detectable are now easily seen on the image with outstanding clarity,” the authors write.

Injecting metals in the heart doesn’t sound like the safest job in the world. In truth, gallium at this temperature is chemically inert and isn’t toxic for humans. Pumping out the metal is easy and doesn’t leave residues. More tests are required before any clinical trials are made. Soon enough, by the likes of it, we’ll have a new sharp look at the human body.

Journal article

baby_brain

Baby brains grow to half the adult size in just 90 days

baby_brain

Researchers performed MRI scans on babies to see how their brains developed from birth to later stages. Their findings reveal the explosive growth of the human brain following birth: in just 90 days, the baby brain grows by 64% its initial size reaching half the adult size.

[ALSO READ] Baby brains benefit from music, even before they walk

They grow up so fast

Traditionally, brain growth is followed the old fashioned way using a measuring tape. This way, doctors casually record skull, and consequently brain growth and if any deviations from a known patterns are encountered, they then further investigate. For instance, premature babies have a smaller brain and develop slower than those delivered at term. As we all know, skulls vary in shape and size and they’re not the best metric for gauging brain size.

[INTERESTING] Babies can tell two languages apart as early as seven months of age

Lucky for scientists, there are MRI scanners. Researchers at University of California scanned the brains of 87 babies, healthy and delivered at term, from birth until three months of age. They saw the most rapid changes immediately after birth – newborn brains grew at an average rate of 1% a day. This slowed to 0.4% per day at the end of the 90-day period. The highest growth rate among brain structures was for the cerebellum, an area of the brain involved in movement. Oppositely, the hippocampus which is responsible for memory formation and retrieval showed the least growth. Apparently, in its early stages the brain wants to concentrate resources on getting the heck out – ‘guh, guh, dadah’ is enough for now.

 

“This is the first time anyone has published accurate data about how babies’ brains grow that is not based on post-mortem studies or less effective scanning methods,” Dr Martin Ward Platt, a consultant paediatrician at the Royal Victoria Infirmary in Newcastle.

“The study should provide us with useful information as this is an important time in development.

“We know, for example, if there are difficulties around the time of birth, a baby’s growth can fall away in the first few months.”

[RELATED] Why you don’t have memories before age 3-4 

By closely following brain development in its early formation days, researchers hope to spot clues that might help them  identify early signs of developmental disorders such as autism.Scientists will now investigate whether alcohol and drug consumption during pregnancy alters brain size at birth. Findings appeared in JAMA Neurology.

 

Dogs’ Brains Respond to People’s Voices the Same Way We Do, MRI study shows

If you’ve ever had a nice fuzzy feeling whenever you heard the voice of a loved one, then, you’re not alone. If somebody’s ever told you that ‘we need to talk’ and out of their tone  you understood that something’s bad, then again, you’re not alone. A new study has shown that dogs have an uncanny ability of picking up our emotions only from our speech – seeming to sense our emotional currents through changes in the tone of our voice. Ask any dog owner, and they’ll confirm it; but for the first time, the science has been done to confirm this theory.

dogs-in-fmri2

It took a while to get there  though, and kudos to the researchers for getting conscious dogs to stay still enough during the MRIs – I have no idea how they managed to do this. Scanning other animals is normally very difficult, as they need to be both conscious and very still. Thankfully, dogs are very trainable and Attila Andics, a researcher in the MTA-ELTE Comparative Ethology Research Group in Budapest and his team, managed to train 11 dogs (golden retrievers and border collies) to rest in an MRI machine. That allowed them to observe the patterns in the dogs’ brains when they heard any of 200 different sounds and compare those responses to humans’. This is the first study which creates a neurological comparison between humans and non-primate animals.

However, we shouldn’t take these findings too far. It’s tempting to draw the conclusion that dogs and humans received their vocal-perception strategies from a common ancestor – but that’s pretty much impossible. If this were the case, then more mammals would also exhibit this – which isn’t happening. Evolutionary biologists are pretty clear on this one.

Andics argues that it’s possible that other mammals do have such a system, since recognition of emotional cues through vocalizations would have been beneficial to all of them. But the other camp claims that this is another simple case of convergent evolution – the same characteristic independently occurring in different animal groups.

Via PBS.

 

 

 

Meditation Could Slow the Progress of Alzheimer’s

Meditation has been shown to have an impact on brain activity, decreasing beta waves and impacting each part differently. Activity in the frontal and parietal lobe slows down, while the flow of information to the thalamus is reduced. This can lead to positive side effects such as improved focus, better memory, and a reduction in anxiety. According to a new study conducted at Beth Israel Deaconess Medical Centre, meditation’s impact on the brain could play an important role in slowing down the progression of Alzheimer’s disease and other cognitive disorders.

Stress, Anxiety, and Dementia

 

Image via Sukadev Bretz, @Flickr.

As people age, their cognitive ability may deteriorate. This can range from mild forgetfulness indicative of aging, to more serious signs of dementia. According to researcher Rebecca Erwin Wells, MD, MPH, approximately 50% of those diagnosed with a mild cognitive impairment may go on to develop dementia within five years of this diagnosis. There is also a link between stress and Alzheimer’s disease. This study was conducted to determine if the practice of stress reduction through meditation might help to delay or stop this progression.

The Study and its Results

The study evaluated 14 adults already diagnosed with mild cognitive impairment, who were broken into two groups. One group met for two hours each week to participate in meditation and yoga, over a period of eight weeks. They were also encouraged to practice at home each day, and participated in a day-long mindfulness retreat. The second group received normal treatment, without the meditation and mindfulness practice. All of the participants had an MRI at the beginning of the study, as well as after eight weeks to see if there were changes in brain activity.

Memory tests were also conducted at the beginning and end of the study. Although there were few differences between the two groups in memory, there was a difference in the MRI imaging results. Although both groups experienced some atrophy of the hippocampus, the area responsible for learning and memory, those who practiced meditation experienced this to a lesser degree. This suggests that an intervention with practices such as meditation and yoga could potentially impact the areas of the brain that are most vulnerable to cognitive disorders such as Alzheimer’s.

Future Implications

While this study was small in scope, it backs up what many alternative therapy practitioners believe; that meditation can improve brain function and significantly reduce stress. If you look at aged care courses at Now Learning or in many universities, meditation is often suggested as a possible therapy for aging patients. Meditation is a simple intervention, with extremely minimal negative side effects. If it could help delay the symptoms of Alzheimer’s even for a short period of time, this can improve the quality of life of aging patients. At the moment, there are no therapies to prevent the progression to dementia, which makes this link worth investigating in greater depth.

radiology

Some 90% of radiology services in the U.S. hospitals are outsourced. Moving health care overseas?

radiology

Photo credit: qbradiology.com

Generally, you can view services like any other commodity and apply strict goods economics. So if the same type of service is available elsewhere, even in another country, at a cheaper price it makes sense, economically, to outsource. Is health care a different matter, however? Apparently, if you took an X-ray in the past decade, there’s a 90% chance it was read by somebody elsewhere in the world, let alone in your hospitals’ vicinity.

“How may I help you?”

In the past two decades or so, outsourcing of US services has risen dramatically, in part lending to the weakening of the economy in the long term. Who hasn’t called customer support to be greeted by a non-native speaker who sympathizes with your problem even though he’s six thousand miles away. There are so many Indian outsourcing jokes that’s hard to keep up, but is there anything to joke about outsourcing health care services? How dangerous really can this be, and do the benefits outweigh the downsides?

The short answer is: it depends, according to  Jonathan Clark, assistant professor of health policy and administration at Penn State. Clark points out that besides radiology services, most hospital in the U.S. today outsource a variety of other medical services as well including anesthesiologist staffing and emergency physician staffing.

“Hospitals outsource the management of physicians from a physician management company. In other words, they buy physicians’ time from a management company. In this way, they get dedicated physicians who, for the most part, only work for their hospital. This is not necessarily the same thing as outsourcing radiological services, where hospitals send images out and it could be read by one of 1,000 radiologists,” Clark says.

Benefits of health care outsourcing

One can understand why hospitals would want to do this in the first place, and after all there are some overall benefits to the practice.

“Anytime health care organizations can get better at what they do, whether that involves outsourcing or not, that’s a good thing for our economy,” he says. “When it comes to U.S. health care — an industry with serious access problems — if we can become more efficient and thereby reduce those access problems, that is a good thing.”

Clark warns however that health care services can’t be outsources in the same way you would manufacturing, for instance.

“One of the assumptions people make is that outsourced services are like commodities in which one unit of service is the same as another unit of service,” he says. “With regard to radiological services, this would mean that providing a radiological read for a patient in Stockton, California, isn’t any different from providing a read for a patient in Miami, Florida.”

Can you outsource patient relationships?

After closely examining radiology performance, Clark found that the accuracy with which a radiologist reads an X-ray or MRI is directly dependent on how much experience the person has with the hospital the patient came in and not with the overall number of reads the radiologist made.

“Our results suggest that there is some customer specificity,” he explains. “If that is the case, someone might say why should we outsource? Shouldn’t we just employ them? But we found that customer specificity may also be transferrable to the outsourcing firm as a whole. So over time the outsourcing company may be able to turn that specificity into an organizational capability rather than a capability that’s embedded in one radiologist’s experience with a hospital.”

Overall, Clark believes there are some benefits to outsourcing radiology services in particular, but believes other health care services are more troublesome to outsource and should be closely followed.

“If you’re mixing and matching anesthesiologists and emergency physicians in a way that’s not permitting them to develop relationships with people at a specific hospital or to become familiar with the culture of the hospital and the team dynamics of the organization, that creates a little more concern, especially with professionals like anesthesiologists or emergency physicians who frequently deal with life and death situations,” Clark notes.

Brain scans of rappers offer valuable insight on creativity

Freestyle rapping is perhaps the most prized skill in hip hop – it is the ability to make rhymes on the fly, and it’s usually what rappers do to “duel” – the one who makes the better insults win.

But Siyuan Liu and Allen Braun, neuroscientists, didn’t go to a rap show – they brought the rap show to the lab. They and their team had 12 rappers freestyle in a magnetic resonance imaging (fMRI) machine. The artists were also asked to recite some memorized lyrics chosen by scientists. By comparing their brain when they were reciting from their memory to improvising, they were able to see which areas of the brain are used in improvisation – and are linked to creativity.

This study complements that conducted by Braun and Charles Limb, a doctor and musician at Johns Hopkins University in Baltimore, Maryland, who did the same thing to jazz musicians while they were improvising. Both sets of artists showed increased activity in a part of their frontal lobes called the medial prefrontal cortex. It can also be inferred that areas inactive in the process are unrelated to the creation process.

“We think what we see is a relaxation of ‘executive functions’ to allow more natural de-focused attention and uncensored processes to occur that might be the hallmark of creativity,” says Braun.

Rex Jung, a clinical neuropsychologist at the University of New Mexico in Albuquerque has also put a lot of effort into understanding the links between the brain and creativity, and he believes the highlighted areas are active in all creative processes, not only in music.

“Some of our results imply this downregulation of the frontal lobes in service of creative cognition. [The latest paper] really appears to pull it all together,” he says. “I’m excited about the findings.”

Michael Eagle, a study co-author who also raps in his spare time and provided inspiration for this study believes the creation process comes somehow outside of the “conscious awareness”:

“That’s kind of the nature of that type of improvisation. Even as people who do it, we’re not 100% sure of where we’re getting improvisation from.”

The next step in the research however will require something different than freestyle rapping; neuroscientists want to find out what happens after that first phase of creative burst.

“We think that the creative process may be divided into two phases,” he says. “The first is the spontaneous improvisatory phase. In this phase you can generate novel ideas. We think there is a second phase, some kind of creative processing [in] revision.”

This is a diffusion spectrum MR image of human brain showing curvature of two-dimensional sheets of parallel neuronal fibers that cross each other at right angles. (c) Massachusetts General Hospital

The Human brain might be organized a whole lot simpler than previously thought. Imaging reveals 3-D grid structure

This is a diffusion spectrum MR image of human brain showing curvature of two-dimensional sheets of parallel neuronal fibers that cross each other at right angles. (c) Massachusetts General Hospital

This is a diffusion spectrum MR image of human brain showing curvature of two-dimensional sheets of parallel neuronal fibers that cross each other at right angles. (c) Massachusetts General Hospital

The most complex object on Earth is the human brain. However, even though it’s intertwined by billions of nerve fibers almost in a chaotic fashion, scientists who have used sophisticated mathematical analysis of advanced imaging data found that the neural pathways that carry electrical signals through the brain are arranged in a very simple manner, resembling a grid. This counter-intuitive finding suggests that the neural structure is extremely simple, underlying the complexity of the brain.

“We found the brain is built from parallel and perpendicular fibers that cross each other in an orderly fashion. Finding this kind of simple organization in the forebrain of higher animals was completely unsuspected,” says Van Wedeen, MD, of the Martinos Center for Biomedical Imaging at Massachusetts General Hospital, who led the study. “Knowing there is a simple plan that, modified by evolution and development, gives rise to all brains has implications for researchers working to build an atlas of brain connections, for pursuing investigation of how the brain develops and for expanding theories of how the brain works.”

This staggering conclusion was made after the researchers, lead by Van Wedeen of Massachusetts General Hospital in Boston, employed a variation of  magnetic resonance imaging (MRI) that harnesses the diffusion of water in brain tissue. Previous research which tried to map the neural pathways of higher order animals, like primates, had been challenging because  each pathway crosses many others within a small space, making them difficult to interpret.

Mapping the brain’s grid

A detail of a diffusion spectrum MR image of rhesus monkey brain showing the sheet-like, three-dimensional structure of neural pathways that cross each other at right angles. (c) Massachusetts General Hospital

A detail of a diffusion spectrum MR image of rhesus monkey brain showing the sheet-like, three-dimensional structure of neural pathways that cross each other at right angles. (c) Massachusetts General Hospital

The method employed by the researchers in the present study basically tracks the movement of water molecules, which they used to brain brain nerves, but at the same time also highlight where these fibres cross. Four species of non-human primates (rhesus monkeys, owl monkeys, marmosets and galagos), together with human volunteers, have had their brains analysed using diffusion spectrum MR imaging. Mathematical analysis of all crossing or adjacent pathways in the brains showed that these were either perpendicular or parallel to the original pathway. Lower primates, like the Galago bushbaby, had a much more evident grid structure, revealing sheets of parallel fibres running at 90 degrees to each another, however moving up towards the primate tree showed that the pathways became progressively slightly more curved, still the grid-like structure was still preserved in humans as well.

This new grid structure finding might explain how the brain evolved progressively this well, considering a tangled up structure would make it difficult for mutations to  increment changes in connectivity.

“I don’t think anyone suspected the brain would have this sort of pervasive geometric pattern,” Wedeen says. “Although our findings could be described as a new longitude and latitude for the brain, they’re also leading us to an entirely new understanding of how and why the brain is organized the way it is. The old image of the brain as a tangle of thousands of discrete, unconnected wires didn’t make sense from an evolutionary standpoint. How could natural selection guide each of those wires into more efficient, advantageous configurations?

“The very simplicity of this grid structure is the reason why it can accomodate the random, gradual changes of evolution,” he continues. “It’s easier for a simple structure to change and adapt, whether we’re talking about the big changes that occur across evolution or the changes that can occur during an individual’s lifetime – both the normal neuroplasticity associated with development and learning or the damage that results from injury or disease. A simple grid structure makes both evolutionary and develomental sense.”

All extremely interesting, and if proven correct, the findings could have some important consequences on future brain studies. However, diffusion MRI can’t detect nerve fibres directly, instead it reconstructs images based on the movement of water molecules in a magnetic field. This makes the data interpretative and subjected to interference factors.  The present study is sure to stir controversy, but all for the best – more effort will be directed towards studying neural pathways.

The findings were published in the journal Science.

 

The interior spongy bone of a rabbit femoral head. (c) Yale University

New MRI technique allows 3-D imaging of non-living material

Researchers at Yale University have successfully mange to utilize a novel MRI technique to 3-D image the insides of hard and soft solids, like bone and tissue, opening the way for a new array of applications, like previously difficult to image dense objects.

 The interior spongy bone of a rabbit femoral head. (c) Yale University Typically, magnetic resonance imaging (MRI) can produce a 3-D image of an object by using an array of powerful magnets and bursts of radio waves which target hydrogen atoms in the respective object. These hydrogen atoms absorb the radio waves, and then emit them back, revealing their precise location. A computer then interprets these signals and “paints” a picture. It’s a very simple, yet highly productive technique, which is why MRI is so popular, especially in the medical field. However, it’s greatest disadvantage is that it needs a lot of hydrogen to read an object, and as such it only works on water-rich materials, like flesh or the human brain. Bones, very tough materials, rocks or basically almost anything that’s non-living can’t be imaged through MRI, until so far at least.

The Yale scientists have developed a new method for MRI imaging, which they call “quadratic echo MRI of solids,” that works by targeting phosphorus atoms instead of hydrogen atoms. A more complicated sequence of radio waves pulses are fired for them to interact with phosphorus, a fairly abundant element in many biological samples, allowing for high-spatial-resolution imaging.

In the paper published recently in the journal PNAS, the Yale team report on various experiments designed to generated 3D MRIs using the phosphorus technique. They thus performed high-resolution 3D images of ex vivo animal bone and soft tissue samples, including cow bone and mouse liver, heart, and brains.

“This study represents a critical advance because it describes a way to ‘see’ phosphorus in bone with sufficient resolution to compliment what we can determine about bone structure using x-rays,” said Insogna, a professor at Yale School of Medicine and director of the Yale Bone Center. “It opens up an entirely new approach to assessing bone quality.”

The researchers say this new type of MRI would complement traditional MRI, not supplant it. MRI of solids should also be possible with elements other than phosphorus, they say.

The researchers believe this new type of MRI imaging should be used to complement the traditional MRI already in place, and claim that MRI imaging of solids through other elements other than hydrogen or phosphorus should be possible. The quadratic echo MRI technique, however, can’t be used on living beings – for one it generates way too much heat. Immediate applications include archaeology, geology, oil drilling.

Scientists can color the MRI images to highlight organs. The heart is shown in lighter colors in the posterior part of the body. (c) Gavin Merrifield

MRI scan reveals tarantulas have double heartbeat

Scientists can color the MRI images to highlight organs. The heart is shown in lighter colors in the posterior part of the body. (c) Gavin Merrifield

Scientists can color the MRI images to highlight organs. The heart is shown in lighter colors in the posterior part of the body. (c) Gavin Merrifield

Biologists from Edinburgh University might have stumbled across a significant discovery, after strapping a tarantula to a magnetic resonance imaging scanner, which showed how its heart contracted in a unique double beat. The find might apply to a species of spiders.

If your curious to see the strange double heart beat for yourself, scientists have a video up on the university’s website.

“In the videos you can see the blood flowing through the heart and tantalizingly it looks as though there might be ‘double beating’ occurring; a distinct type of contraction which has never been considered before,” said Gavin Merrifield in a press release.

Previous spider cardiac research were either indirect or highly invasive, however the Scottish biologists came to more accurate results by measuring heart rate and cardiac output with an MRI scanner. Merrifield presented the research at the Society for Experimental Biology Annual Conference in Glasgow last month.

Although  MRI use is often medical in reason, it’s been known to have implications in study advancements of other branches of biology.

“One potential practical use of this research is to ascertain the chemical composition of spider venom,” says Mr. Merrifield. “Venom has applications in agriculture as a potential natural pesticide. On the more academic side of things if we can link MRI brain scans with a spider’s behaviour, and combine this with similar data from vertebrates, we may clarify how intelligence evolved.”

 

 

Brain solves problems when we daydream

As an old saying goes, time spent wishing is time wasted. I’m guessing day dreaming goes into the same category, right?? Wrong. According to a study published in the Proceedings of the National Academy of Sciences activity in numerous brain regions actually increases when our mind wanders off to a different place.

The study led by researchers from the University of British Columbia pointed out that brain areas associated with solving complex problems are highly active during this time, contrary to what was previously believed, that they were inactive.

“Mind wandering is typically associated with negative things like laziness or inattentiveness,” says lead author, Prof. Kalina Christoff, UBC Dept. of Psychology. “But this study shows our brains are very active when we daydream – much more active than when we focus on routine tasks.”

People can spend up to 1/3 of their wake time day dreaming (personally, I find it a bit of a stretch), so it was already known that this state is pretty important and should be studied and understood thoroughly, but as it turns out, it’s role as a cognitive state is much more important than previously believed.

“When you daydream, you may not be achieving your immediate goal – say reading a book or paying attention in class – but your mind may be taking that time to address more important questions in your life, such as advancing your career or personal relationships,” says Christoff.