Tag Archives: #movement

Newfound Ability to Change Baby Brain Activity Could Lead to Rehabilitation for Injured Brains (Neuroscience)

Researchers from King’s College London have identified the brain activity for the first time in a newborn baby when they are learning an association between different types of sensory experiences. Using advanced MRI scanning techniques and robotics, the researchers found that a baby’s brain activity can be changed through these associations, shedding new light on the possibility of rehabilitating babies with injured brains and promoting the development of life-long skills such as speech, language and movement.

Published recently in Cerebral Cortex, the researcher builds on the fact that learning associations is a very important part of babies’ development but the activity inside the brain that was responsible for learning these associations was unknown and unstudied.

Lead researcher, Dr Tomoki Arichi said it is the first time it has been shown that babies’ brain activity can be altered through associative learning – and in particular, brain responses become associated with particular stimuli, in this case, sound.

“We also found that when a baby is learning, it actually is activating lots of different parts of the brain, so it is starting to incorporate the ‘wider network’ inside the brain which is important for processing activity,” he said.

A total of 24 infants were studied by playing them a sound of a jingling bell for six seconds, coupled with a gentle movement induced by a custom-made 3D printed robot strapped to their right hand.

During this time, the resulting brain activity was measured using functional MRI (fMRI). After 20 minutes of learning an association between the two types of stimuli, the babies then just heard the sound on its own and the resulting brain activity was compared to that seen before the period of learning.

Dr Arichi said not only do the results provide new information about what is happening inside the normal baby brain when it is learning, but also have implications for the injured brain.

If a baby was not capable of processing movement, or movement is not associated with normal activity inside the brain (such might be the case in a baby with cerebral palsy), clinicians could then be able to induce that activity by learning an association with sound, and using the sound simulation to try and amplify and rehabilitate their movement.

“With our findings it raises the possibility of trying to do something to help with that through targeted stimulation and learning associations,” Dr Arichi said.

“It is possible to induce activity inside the part of the brain that normally processes movement, for instance, just by using a single sound. This could be used in conjunction with rehabilitation or to try and help guide brain development early in life.”

When babies are born, they have a new sensory experience around them that is completely different to what they would have been experiencing inside the womb.

They must then start to quickly understand their environment and the relationships between different things happening, which is even more important in babies that have injuries to their brain.

The researchers sought to understand how babies start to learn these key relationships between different kinds of sensory experiences and how this then contributes to the early stages of overall brain development.

“A baby’s brain is constantly learning associations and changing its activity all the time so that it can respond to the new experiences that are around it,” Dr Arichi said.

“In terms of influencing patients and interpreting it in a wider context, what it means is that we should be thinking about how we could help with disorders of brain development from a very early stage in life because we know that experience is constantly shaping the newborn brain’s activity.”

References: S Dall’Orso, W P Fifer, P D Balsam, J Brandon, C O’Keefe, T Poppe, K Vecchiato, A D Edwards, E Burdet, T Arichi. Cortical Processing of Multimodal Sensory Learning in Human Neonates. Cerebral Cortex, 2020; DOI: 10.1093/cercor/bhaa340 https://academic.oup.com/cercor/advance-article/doi/10.1093/cercor/bhaa340/5988757

Provided by King’s College London

Group Size And Makeup Affect How Social Birds Move Together (Biology / Zoology)

Scientists have used high-resolution GPS tracking methods to provide new insights into how differently sized animal groups move and interact with their environment.

Scientists have shown that the size and makeup of groups of social birds can predict how efficiently they use and move through their habitat, according to new findings published today in eLife.

This photo shows some of the vulturine guineafowl from the study by Danai Papageorgiou and Damien Farine. ©Damien R Farine (CC BY 4.0)

The study suggests that intermediate-sized groups of vulturine guineafowl – a ground-dwelling social bird found in east African savannahs – exhibit the most effective balance between a decreased ability to coordinate movements and increased accuracy of navigation.

These findings add to our understanding of a key question in animal sociality – namely, whether groups have an optimal size – by showing that the number of individuals in a group determines the ability of that group to make the most effective use of their environment.

“For many social animals, larger groups benefit from information pooling, where inputs from multiple individuals allow for more accurate decisions about navigation,” explains first author Danai Papageorgiou, IMPRS Doctoral Student at the Department of Collective Behaviour, Max Planck Institute of Animal Behavior, and at the Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Germany. “However, as groups become larger they start to face challenges in coordinating their actions, such as reaching a consensus about where to go next or maintaining cohesion as they move through vegetation.”

Papageorgiou and her PhD advisor, Professor Damien Farine, investigated the relationship between the size and collective movement of groups of vulturine guineafowl. They predicted that the optimal group size of these birds would be determined by the balance between their ability to coordinate movement and their ability to make accurate decisions when navigating.

The team fitted individual birds from 21 distinct social groups with GPS tags and collected movement data over five two-month-long seasons. They used these data to calculate the groups’ habitat use, including their home-range size, the distance that they travelled each day and their movement speed while ‘on the go’. By observing the groups each week, they could also measure the size of each group and record their makeup. Specifically, they recorded the number of chicks in each group, as they predicted that the birds’ movement abilities may be restricted when there are more chicks because they are slower and much more vulnerable to predators.

The researchers found that intermediate-sized groups, consisting of 33-37 birds, ranged over larger areas and achieved this by travelling shorter distances each day, compared to smaller and larger groups. They also explored the most new areas. These results suggest that intermediate-sized groups were more efficient in using the space, potentially encountering more resources while spending less energy and lowering their chances of being tracked by predators. Additionally, data collected on the birds’ reproductive success reinforced the fact that intermediate-sized groups benefited from these movement characteristics, as they also had more chicks.

However, the study also found interesting consequences of having a beneficial group size for movements. Groups with many chicks, despite being the optimal size, had more restricted home ranges. This was likely because the chicks needed more protection from predators, and therefore stayed in the protected vegetation for longer periods of time, and their small sizes slowed down the group while moving.

As a result, the study showed that intermediate-sized groups were in fact rarer than smaller and larger groups. Papageorgiou and Farine suggest this is because the benefits of being in an optimal-sized group makes the size of these groups less stable. For example, higher reproductive success inevitably pushes the group past its optimal group size.

“Our study highlights how all groups are not equal, with the effects of group size and composition playing a major role in shaping how social species use their habitat,” Farine says. “What is particularly interesting is that optimally sized groups are not expected to be common. Future studies should investigate whether these relationships change across different environmental conditions, and how animal groups cope with the different challenges that each season brings.”

References: Danai Papageorgiou, Damien Roger Farine, “Group size and composition influence collective movement in a highly social terrestrial bird”, Ecology, 2020. https://elifesciences.org/articles/59902

Provided by Elife

Study Finds 5 Distinct Dog Types From 11,000 Years Ago (Archeology)

Texas A&M Professor Anna Linderholm and a team of researchers examined dog DNA to learn about movement and patterns of ancient dogs and their relationship with humans.

An international team of researchers that includes a Texas A&M University professor has studied the lineage of dogs and found that there were at least five different types of dogs as far back as 11,000 years ago.

Research shows dogs were already splitting into different types 11000 years ago. ©gettyimages.

Anna Linderholm, director of the BiG (bioarchaeology and genomics) Laboratory and an archaeologist at Texas A&M, and a team of worldwide researchers have had their work published in the current issue of Science magazine.

The team studied dog DNA dating as far back as 11,000 years ago, immediately following the last Ice Age. By sequencing the DNA of 27 dogs found in Europe, the Near East and Siberia, team members discovered five different types of dogs with distinct genetic ancestries dating from before any other animal had been domesticated.

Linderholm was part of the genomics team that extracted DNA from skeletal material to see how dogs evolved from thousands of years ago when all humans were still hunters and gatherers.

“We examined dogs from across the old world, and they represent a period that stretches almost 11,000 years back in time,” she said.

“The dog samples have been gathered from museums, and other collections from across the world and by several members of this team. Since we don’t know when and where dogs were domesticated, we have collected most of the known dogs from the old world, going back as far in time as possible and using dog DNA that has been best preserved.”

Linderhom said that samples were taken from collected dog remains, such as a tooth or a piece of bone. From the samples, the DNA was sequenced, enabling the team to read the genetic code that explains the origins of each dog and how it might have been related to modern-day dogs.

“By looking at a dog’s genome, we can look at that dog’s history, look at his parents and their parents and so on,” she said. “It is much like today when people do an ancestry test for humans, trying to find out where they come from.”

Linderholm added that dogs look similar genetically, meaning they share a more recent common ancestor.

“The five linages from over 11,000 years ago is more diversity than we have been able to identify before,” she said. “Having said this, all dogs seem to have originated from one ancient wolf population, a wolf population that has since disappeared. We have no connection with our modern-day wolf populations with our first domesticated dogs.”

She added that the human-dog bond can now be seen a bit more clearly. When humans moved, they almost always took their dogs with them.

“We see this happening when farming was introduced into Europe and other areas such as the Steppes in Asia,” she said. “We note a clear link between the movement of people and the introduction of a new type of dogs. This is new, and we also don’t see this pattern repeating itself when we have another large population movement. So humans were not always consistent in their actions at this time, but we do see a much greater connection between humans and their dogs, more so than any other animal.”

References: Anders Bergström, Laurent Frantz, Ryan Schmidt et al., “Origins and genetic legacy of prehistoric dogs”, Science 30 Oct 2020:, Vol. 370, Issue 6516, pp. 557-564, DOI: 10.1126/science.aba9572

Provided by Texas A&M University

Primates Aren’t Quite Frogs (Neuroscience)

Spinal modules in macaques can independently control forelimb force direction and magnitude.

Researchers in Japan demonstrated for the first time the ‘spinal motor module hypothesis’ in the primate arm, opening a new pathway for recovery after disease or injury.

An experiment nearly 40 years ago in frogs showed that their leg muscles were controlled by simultaneously recruitment of two modules of neurons. It’s a bit more complex in macaques (The National Center of Neurology and Psychiatry).

The human hand has 27 muscles and 18 joints, which our nervous system is able to coordinate for complex movements. However, the number of combinations — or degrees of freedom — is so large that attempting to artificially replicate this control and adjustment of muscle activity in real time taxes even a modern supercomputer. While the method used by the central nervous system to reduce this complexity is still being intensely studied, the “motor module” hypothesis is one possibility.

Under the motor module hypothesis, the brain recruits interneuronal modules in the spinal cord rather than individual muscles to create movement; wherein different modules can be combined to create specific movements. Nearly 40 years ago, research in frogs showed that simultaneously recruiting two modules of neurons controlling leg muscles created the same pattern of motor activity that represents a “linear summation” of the two component patterns.

An international team of researchers, led by Kazuhiko Seki at the National Center of Neurology and Psychiatry’s Department of Neurophysiology, in collaboration with David Kowalski of Drexel University and Tomohiko Takei of Kyoto University’s Hakubi Center for Advanced Research, attempted to determine if this motor control method is also present in the primate spinal cord. If validated, it would provide new insight into the importance of spinal interneurons in motor activity and lead to new ideas in movement disorder treatments and perhaps even a method to “reanimate” a limb post-spinal injury.

The team implanted a small array of electrodes into the cervical spinal cord in three macaques. Under anesthesia, different groups of interneurons were recruited individually using a technique called intraspinal microstimulation, or ISMS. The team found that, as in the frog leg, the force direction of the arm at the wrist during dual-site simulation was equal to the linear summation of the individually recruited outputs. However, unlike the frog leg, the force magnitude output could be many times higher than that expected from a simple linear summation of the individual outputs. When the team examined the muscle activity, they found that this supralinear summation was in a majority of the muscles, particularly in the elbow, wrist, and finger.

“This is a very interesting finding for two reasons,” explains Seki. “First, it demonstrates a particular trait of the primate spinal cord related to the increased variety of finger movements. Second, we now have direct evidence primates can use motor modules in the spinal cord to control arm movement direction and force magnitude both efficiently and independently.”

In effect, using paired stimulation in the primate spinal cord not only directly activate two groups of interneurons, INa and INb, which recruit their target muscle synergies, Syn-a and Syn-b, to set the arm trajectory, but can also activate a third set of interneurnons that can adapt the motor activity at the spinal level to change the force of the movement, group INc. This would let the brain plan the path the arm should take while the spinal cord adapts the muscle activity to make sure that path happens.

One example of this “plan and adapt” approach to motor control is the deceptively simple act of drinking from a can of soda. The brain can predetermine the best way to lift the can to your mouth for a sip, but the actual amount of soda in the can — and therefore the can’s weight — is perhaps unknown. Once your brain has determined the trajectory the can should take — in this case INa and INb — the amount of force needed to complete that action can be modulated separately in INc, rather than redetermining which sets of muscles will be needed.

This study experimentally proves for the first time that primate arm movements may be efficiently controlled by motor modules present in the spinal cord. Based on the results of this research, it is expected that the analysis and interpretation of human limb movements based on the motor module hypothesis will further advance in the future.

In the field of robotics, this control theory may lead to more efficient methods to create complex limb movements, while in the field of clinical medicine, it is expected that new diagnostic and therapeutic methods will be created by analyzing movement disorders caused by neurodegenerative diseases and strokes.

References: Amit Yaron, David Kowalski, Hiroaki Yaguchi, Tomohiko Takei, and Kazuhiko Seki, “Forelimb force direction and magnitude independently controlled by spinal modules in the macaque”, Proceedings of the National Academy of Sciences of the United States of America, 2020. DOI】https://doi.org/10.1073/pnas.1919253117

Provided by Kyoto University

New Theory Predicts Movement Of Different Animals Using Sensing To Search (Biology / Animals)

Northwestern University research team has developed a new theory that can predict the movement of an animal’s sensory organs while searching for something vital to its life.

Whether its us, or an animals, or birds or an insect, we are relied on our senses that help us to navigate and survive in our world. But what drives this essential sensing?

Unsurprisingly, animals move their sensory organs, such as eyes, ears and noses, while they are searching. Take an example of cat, she swivel her ears to capture important sounds without needing to move its body. But the precise position and orientation these sense organs take over time during behavior is not intuitive, and current theories do not predict these positions and orientations well.

Now, the researchers in the current study developed a new theory called ‘energy-constrained proportional betting’ which provides a unifying explanation for many enigmatic motions of sensory organs that have been previously measured.

They applied this theory to four different species which involved three different senses (including vision and smell) and found the theory predicted the observed sensing behavior of each animal. The theory could be used to improve the performance of robots collecting information and possibly applied to the development of autonomous vehicles where response to uncertainty is a major challenge.

The algorithm that follows from the theory generates simulated sensory organ movements that show good agreement to actual sensory organ movements from fish, mammals and insects. The algorithm shows that animals trade the energetically costly operation of movement to gamble that locations in space will be informative. The amount of energy (ultimately food they need to eat) they are willing to gamble, the researchers show, is proportional to the expected informativeness of those locations.

The study focuses on South American gymnotid electric fish, using data from experiments performed in MacIver’s lab, but also analyzes previously published datasets on the blind eastern American mole, the American cockroach and the hummingbird hawkmoth. The three senses were electrosense (electric fish), vision (moth) and smell (mole and roach).

The theory provides a unified solution to the problem of not spending too much time and energy moving around to sample information, while getting enough information to guide movement during tracking and related exploratory behaviors.

The algorithm is a modified version of one Murphey and MacIver developed five years ago in their bio-inspired robotics work. They took observations of animal search strategies and developed algorithms to have robots mimic those animal strategies. The resulting algorithms gave Murphey and MacIver concrete predictions for how animals might behave when searching for something, leading to the current work.

References: Chen Chen, Todd D Murphey, Malcolm A MacIver, “Tuning movement for sensing in an uncertain world”, Computational and systems biology (eLife), 2020. DOI: 10.7554/eLife.52371 link: https://elifesciences.org/articles/52371

Side Stitches May Be Caused By An Organ You’ve Never Heard Of (Biology)

What causes that cramp in your side during exercise? It turns out that scientists don’t actually know. There have long been two prevailing theories. The first is that it comes from a cramp in your diaphragm, the muscle that enables your lungs to fill with air. This may seem likely on its face, but it doesn’t hold up when you think about the fact that side aches are a common ailment of horseback riders, who aren’t breathing heavily when it happens. The second theory is that the pain comes from a jostling of your organs during excessive movement. This doesn’t really hold up either, as anyone who has had a side stitch can tell you it’s in a single area, not all over.

Many experts are turning to another theory: irritation of the parietal peritoneum. You may have never heard of this membrane, which lines your abdominal and pelvic cavity, but scientists—including the authors of a 2003 paper in the British Journal of Sports Medicine—think it’s the most likely culprit of that mid-workout pain. Irritated by excessive movement? Check. Causes pain in a single area? Check. This organ also explains the other causes of side stitches, such as exercising after a large meal (a full belly puts pressure on the membrane), and fatigue in the middle of a long workout session (tired core muscles can make you slouch, and a slouching spine can irritate the membrane). The case isn’t closed on the side-stitch mystery, but the parietal peritoneum is definitely the biggest suspect.