Tag: Neurology

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Science

Stony Brook researchers build on U of R Alzheimer’s research

Photo: <a href="http://www.flickr.com/photos/edkohler/2712742904/sizes/l/">edkohler</a> @ Flickr.com

In August of last year, we reported on the recent discovery of a “Glymphatic Pathway,” which is essentially a waste-disposal system for the brain. This system, discovered by Jeffrey Iliff and Maiken Nedergaard of the University of Rochester, mirrors the role of the lymphatic system in other organs of the body. The system removes waste proteins from the brain and the effective running of this system, scientists believe, is the difference between a healthy brain and one with Alzheimer’s Disease.

Building on that research, boffins at the University of Stony Brook used tracing elements and MRI scanning to trace the entire glymphatic system, from the back of the brain to the nasal cavity, to better understand the pathway and what a damaged one might look like:

This advanced imaging technique has the potential to be used as a way to monitor the human brain to map brain waste clearance and access (sic) disease susceptibility. Theoretically, if clinicians were able to capture a defect in the glymphatic system where certain channels are malfunctioning, plaque formation would likely accelerate, Benveniste says.

This plaque buildup may be an early sign of disease susceptibility before evidence of any cognitive changes. Though there is no known way to repair malfunctions in the glymphatic system, the research team is investigating ways to repair or open malfunctioning channels.

Mapping out this system is part of a wider effort to understand “white matter” in the neurological system.

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Science

Heavy Petting: how nerve endings in your skin make petting awesome.

Photo: <a href="http://www.flickr.com/photos/nickwebb/3968719105/sizes/l/">Nick J Webb</a> @ Flickr.com

Petting. Your dog loves it. You love it. Which makes you watching your dog love it… a little weird. But the truth is, from humans to cats and dogs and beyond, social mammals adore being gently stroked down their bodies. Whether that body is furry or covered in the finest patina of hair, the results are the same.

California Institute of Technology researchers happened upon the reason for this phenomenon while studying a specific type of neuron commonly found in hairy or furry mammals’ skin. These cells had been discovered in 2007, but their usefulness to their possessors was not yet known.

The solution was to genetically modify mice so that these particular nerve cells would light up when stimulated. The researchers then used a microscope to see which type of stimulus would ring the bell, so to speak:

They tried various types of stimuli to see if they could get the cells to light up. For example, the scientists recorded each time they stroked the hindfoot of the mouse with an artist’s paintbrush. In this way, they could see if the touch was responsible for the nerve signal. Gentle stroking, but not poking or pinching with a tweezer, elicited a response, Anderson and his colleagues report online today in Nature.

Of course however pleasing and even amorous petting can be, science is not often romantic, and neurology even less so. To wit, the solution for determining whether the soft petting actually did feel good was – you guessed it – more genetic modification, rigorous testing and a healthy dose of drug abuse.

The researchers this time modified the mice so that an injection of a chemical would elicit the same response from the nerves as petting. Wow. Give me a shot of that.

So they put the mice in a three-chambered box. In one chamber, they’re shooting up and listening to the Velvet Underground. In the opposite chamber, diddley-shit and Pat Boone.

Guess what? After a few weeks of conditioning, the mice preferred the petting den. Whether this proves that mice prefer petting or have addictive personalities remains an open question in my mind.

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Science

Is Big Bird really teaching kids?

Photo: PBS

Is television really the brain rot your parents used to tell you it was? Well, the jury is still out about that, but one thing University of Rochester neurology researchers seem to have discovered is that the brain activity of a kid watching Big Bird generally mirrors that of adults. That is: the parts of the brain which are active in an adult watching Sesame Street and those of a child are similar, and also map to specific cognitive aptitudes in both groups.

The study conducted on 27 children and 20 adults used fMRI imaging to watch the brain activity of test subjects as they watched Sesame Street. The purpose of the experiment was to see if doing more natural tasks such as watching television would reveal more clues as to how the brain functions. Previous tests using simplified tasks failed to predict which parts of the brain governed which types of cognitive ability. However, when subjects watched The Bird:

Children whose neural maps more closely resembled the neural maps of adults scored higher on standardized math and verbal tests. In other words, the brain’s neural structure, like other parts of the body, develops along predictable pathways as we mature.

The study also confirmed where in the brain these developing abilities are located. For verbal tasks, adult-like neural patterns in the Broca area, which is involved in speech and language, predicted higher verbal test scores in children. For math, better scores were linked to more mature patterns in the intraparietal sulcus (IPS), a region of the brain known to be involved in the processing of numbers.

On the issue of whether watching television actually teaches children, well, the researchers are quick to point out that they’re not actually endorsing television as an educational tool. Heaven forfend. But the findings of the study do seem at minimum to suggest that the correct neural pathways are getting teased by the content of Sesame Street episodes.

Whether this is because kids are learning from television or simply responding to information they already understand based on some other means of learning is not clear. It is also entirely possible that, just as the simple task-based studies failed to reveal correlations, the current set of studies might be revealing genuine correlations that are not actually tied to the same cause.

But knowing that a correlation does exist opens up entirely new neurological pathways for the continued research of learning and learning disability. With more research and corroborating evidence from other disciplines, this could be a whole new suite of tools to get the best out of kids.

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Science VIDEO

Clean behind your ears. The glymphatic system will clean between them.

Photo: <a href="http://www.urmc.rochester.edu/news/story/index.cfm?id=3584">URMC</a>

Sometimes, there’s nothing more cathartic than taking out the garbage – even for your brain.

Neuroscientists at University of Rochester Medical Center have discovered a previously unrecognized system that drains waste from the brain. Dubbed the “glymphatic system” due to its similarities with the lymphatic system, but instead managed by brain cells known as glial cells, this new-found system brings hope for many brain conditions, including Alzheimer’s Disease, Parkinson’s Disease, stroke, and traumatic brain injuries, which are all attributed in some way to waste protein build up on the brain.

Here’s how it works – the highly organized system acts as a series of pipes, piggybacking off of the brain’s blood vessels to drain away waste products. Think of it as if the brain has two big garbage cans; the first one collecting waste through a gradual trickle, the second one under much more pressure, pushing large volumes daily to carry waste away more forcefully.

That’s a lot going on in our brains on a daily basis – so how were we unaware of all of this until now? According to scientists, the system only works when it’s intact and operating in a living brain, which had previously been extremely difficult. To study the living, whole brain, the team at U of R used a technology known as two-photon microscopy, which allows scientists to look at the flow of blood and other substances in the brain of living animals – in this case, mice.

This is not the first discovery to stem from this research at U of R.  Back in the spring, a similar study found that parts of the brain that were not cleaning properly could be to blame for ADHD.  This is all great news, though. Once a definitive  biological cause has been pinned down with certainty, then medicines can be created to treat the problem.

See? Your mom wasn’t kidding when she told you it’s important to clean!

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Rochester Science

U of R research into forgotten brain cells may shed light on the inner workings of epilepsy, schizophrenia

Photo: Digital Shotgun @ Flickr.com

People with ADHD may have a new part of their brain to blame. Neurons used to take much of the blame for mental disorders. Researchers believed that when neurons stopped doing their job mental disorders occurred. But now it seems there may be another cell in the mix – astrocytes.

Researchers used to consider astrocytes the lowly housekeepers of the brain. But now they’re finding that astrocytes are a much more crucial part to brain activity, may perhaps even play a factor in the development of mental disorders including epilepsy, schizophrenia, and ADD.

Maiken Nedergaard, a neurosurgery professor at the University of Rochester, and colleagues ran a study exploring astrocytes role in the brain. Nedergaard’s team used advanced lasers to look at astrocytes in rats and mice.

Researchers used to think that astrocytes simply absorbed Potassium so that the neurons could do their job. A neuron’s main job is communicating through electrochemical signals. Astrocytes had long been considered “brain glue,” whose main component was giving the brain structure.

Now astrocytes can be thought of more as moms. They clean and make sure neurons are doing everything they need to. It is when astrocytes do not do their job properly that mental disorders can develop. When an astrocyte isn’t doing it’s job of absorbing potassium, neurons start to fire erratically. When neurons fire erratically, they cannot communicate effectively with the rest of the brain.

Knowing that astrocytes are a cause behind some mental disorders, can help researchers develop better treatment. When a definitive biological cause is behind a disorder medicines can be developed to treat it.