New Hypothesis on how the Brain is Organized

Currently, the most accepted theory on the brain is organized by body part. For example, a specific part of the brain controls the feet and a another area controls the arm. However, this theory may come into question after new findings. In a study published in Current Biology, 17 people who were born with one hand were filmed doing everyday tasks and told to move specific body parts while having their brain scanned via MRI. They then repeated the experiment, except this time they used people with two hands. When they compared the results, they were shocked. The part of the brain that was supposed to control the “missing” hand lit up when they used something to replace the missing hand, such as a foot or elbow. For example, if the one armed person was picking something up and used their hand and their elbow, the same parts of the brain would light up as if the person was using two hands. Which led to the new hypothesis that there is no area that controls the hand. Instead, there is an area that controls what the hand usually does. However, this experiment was done with a very small sample size and more experiments will be done. If this new theory is correct, we will need to re-evaluate almost everything we consider to be true about neurological disorders and brain function. Despite this potential setback, this information could lead to a greater understanding of how the brain works which in turns results in greater understanding of disorders.

For more information: http://www.sciencealert.com/how-one-handed-people-are-completely-changing-our-understanding-of-the-brain

Nasal Spray “infiltrates” Blood-Brain Barrier

The Blood-Brain Barrier (BBB) is “highly selective” membrane that separates blood from the cerebrospinal fluid and interstitial fluid in the central nervous system. This barrier is imperative to our survival because it prevents toxins that get into the bloodstream from damaging the brain. This barrier also makes it hard for medicine to affect the brain. A team from the Washington University in St. Louis created a nasal spray that may allow drugs to reach the brain. They created an aerosol spray composed of gold nanoparticles that are small enough to cross through the BBB and fluorescent markers to track where the spray goes. The then sprayed locusts, which have a BBB and a similar olfactory (scent) network. The spray moved through the antenna, then through the olfactory nerves, past the BBB, and into the brain. They then tested the locusts’ olfactory neurons and did not notice any changes, suggesting that the delivery system doesn’t alter brain function. The next steps are to make the nanoparticles “carry” medication, and if successful, test the product on humans. If it does, it would change the way we deliver drugs to the brain. Pills are not precise and the medicine does not always cross the BBB. The other, seemingly more effective delivery system is through injections directly into the CNS, which comes with its own risks.

For more information: http://www.sciencealert.com/new-nasal-spray-crosses-the-blood-brain-barrier-to-deliver-drugs-directly

Scientists Discover How Naked Mole Rats Survive Without Oxygen

Naked mole rats have always been an interesting topic for biologists. They barely feel pain, they can’t get cancer, they live much longer than other rodents, and perhaps most interesting, they can last over 15 minutes without oxygen. Animals about the same size as naked mole rats will die under 45 seconds without oxygen and humans will only survive about 6 minutes without it. Scientists at the University of Illinois at Chicago discovered how these naked mole rats are able to survive such a long time without oxygen. In normal conditions their cells metabolize glucose (glucose metabolism uses oxygen) like every other mammal. However, when there is no oxygen present, they go into a vegetative state and their brain cells start using fructose, which does not require oxygen, to create cellular energy. The mole rats continue to use this pathway until oxygen is available. Once that happens, they wake up and move on as if nothing happened. This was discovered when they exposed the naked mole rats to low oxygen levels and found high fructose levels in their blood. Other mammals can metabolize fructose in their intestines, however, this does not supply the brain cells with energy. Later, the scientists discovered that fructose was being delivered to the brain and the brain cells were metabolizing that fructose. So far, this is the only mammal discovered that can metabolize fructose in their brain. Scientists believe that this was adapted in order to survive in their overcrowded and under ventilated environments.

For more information: http://www.sciencealert.com/we-just-figured-out-how-naked-mole-rats-survive-low-oxygen-and-it-s-even-trippier-than-imagined