squidlysue:

 We’re Only Beginning to Understand How Our Brains Make Maps
by Emily Badger
About 40 years ago, researchers first began to suspect that we have neurons in our brains called “place cells.” They’re responsible for helping us (rats and humans alike) find our way in the world, navigating the environment with some internal sense of where we are, how far we’ve come, and how to find our way back home. All of this sounds like the work of maps. But our brains do impressively sophisticated mapping work, too, and in ways we never actively notice.

Every time you walk out your front door and past the mailbox, for instance, a neuron in your hippocampus fires as you move through that exact location – next to the mailbox – with a real-world precision down to as little as 30 centimeters. When you come home from work and pass the same spot at night, the neuron fires again, just as it will the next morning. “Each neuron cares for one place,” says Mayank Mehta, a neurophysicist at UCLA. “And it doesn’t care for any other place in the world.”

This is why these neurons are called “place cells.” And, in constantly shuffling patterns, they generate our cognitive maps of the world. Exactly how they do this, though, has remained a bit of an enigma. The latest research from Mehta and his colleagues, published this month in the online edition of the journal Science, provides more clues. It now appears as if all of the sensory cues around us – the smell of a pizzeria, the feel of a sidewalk, the sound of a passing bus – are much more integral to how our brains map our movement through space than scientists previously believed.

And the more scientists learn about how our brains construct cognitive maps of space, the more we may learn about how to design those spaces – streets, neighborhoods, cities – in the first place. Or, rather, we may learn more about the consequences of how we’ve built them so far.
[more]

squidlysue:

We’re Only Beginning to Understand How Our Brains Make Maps

by Emily Badger

About 40 years ago, researchers first began to suspect that we have neurons in our brains called “place cells.” They’re responsible for helping us (rats and humans alike) find our way in the world, navigating the environment with some internal sense of where we are, how far we’ve come, and how to find our way back home. All of this sounds like the work of maps. But our brains do impressively sophisticated mapping work, too, and in ways we never actively notice.

Every time you walk out your front door and past the mailbox, for instance, a neuron in your hippocampus fires as you move through that exact location – next to the mailbox – with a real-world precision down to as little as 30 centimeters. When you come home from work and pass the same spot at night, the neuron fires again, just as it will the next morning. “Each neuron cares for one place,” says Mayank Mehta, a neurophysicist at UCLA. “And it doesn’t care for any other place in the world.”

This is why these neurons are called “place cells.” And, in constantly shuffling patterns, they generate our cognitive maps of the world. Exactly how they do this, though, has remained a bit of an enigma. The latest research from Mehta and his colleagues, published this month in the online edition of the journal Science, provides more clues. It now appears as if all of the sensory cues around us – the smell of a pizzeria, the feel of a sidewalk, the sound of a passing bus – are much more integral to how our brains map our movement through space than scientists previously believed.

And the more scientists learn about how our brains construct cognitive maps of space, the more we may learn about how to design those spaces – streets, neighborhoods, cities – in the first place. Or, rather, we may learn more about the consequences of how we’ve built them so far.

[more]

backwardinduction:

Researchers discover how brain circuits can become miswired during development

In the journal Cell, the researchers describe, for the first time, that faulty wiring occurs when RNA molecules embedded in a growing axon are not degraded after they give instructions that help steer the nerve cell. So, for example, the signal that tells the axon to turn—which should disappear after the turn is made—remains active, interfering with new signals meant to guide the axon in other directions. The scientists say that there may be a way to use this new knowledge to fix the circuits. “Understanding the basis of brain miswiring can help scientists come up with new therapies and strategies to correct the problem,” says the study’s senior author, Dr. Samie Jaffrey, a professor in the Department of Pharmacology. “The brain is quite ‘plastic’ and changeable in the very young, and if we know why circuits are miswired, it may be possible to correct those pathways, allowing the brain to build new, functional wiring,” he says. Disorders associated with faulty neuronal circuits include epilepsy, autism, schizophrenia, mental retardation and spasticity and movement disorders, among others. In their study, the scientists describe a process of brain wiring that is much more dynamic than was previously known—and thus more prone to error. Read more at: http://medicalxpress.com/news/2013-06-brain-circuits-miswired.html#jCp

backwardinduction:

Researchers discover how brain circuits can become miswired during development

In the journal Cell, the researchers describe, for the first time, that faulty wiring occurs when RNA molecules embedded in a growing axon are not degraded after they give instructions that help steer the nerve cell. So, for example, the signal that tells the axon to turn—which should disappear after the turn is made—remains active, interfering with new signals meant to guide the axon in other directions. The scientists say that there may be a way to use this new knowledge to fix the circuits. “Understanding the basis of brain miswiring can help scientists come up with new therapies and strategies to correct the problem,” says the study’s senior author, Dr. Samie Jaffrey, a professor in the Department of Pharmacology. “The brain is quite ‘plastic’ and changeable in the very young, and if we know why circuits are miswired, it may be possible to correct those pathways, allowing the brain to build new, functional wiring,” he says. Disorders associated with faulty neuronal circuits include epilepsy, autism, schizophrenia, mental retardation and spasticity and movement disorders, among others. In their study, the scientists describe a process of brain wiring that is much more dynamic than was previously known—and thus more prone to error.

Read more at: http://medicalxpress.com/news/2013-06-brain-circuits-miswired.html#jCp

The Man Who Mistook His Wife for a Hat, Oliver Sacks (via sleepinginthegreenery)
knowledgethroughscience:

Scientists at Princeton University used 3-D printing to create a functional ear that can “hear” radio frequencies far beyond the range of normal human capability.“The design and implementation of bionic organs and devices that enhance human capabilities, known as cybernetics, has been an area of increasing scientific interest,” the researchers wrote in the article which appears in the scholarly journal Nano Letters. “This field has the potential to generate customized replacement parts for the human body, or even create organs containing capabilities beyond what human biology ordinarily provides.”The finished ear consists of a coiled antenna inside a cartilage structure. Two wires lead from the base of the ear and wind around a helical “cochlea” — the part of the ear that senses sound — which can connect to electrodes. The ear in principle could be used to restore or enhance human hearing. Electrical signals produced by the ear could be connected to a patient’s nerve endings, similar to a hearing aid.

knowledgethroughscience:

Scientists at Princeton University used 3-D printing to create a functional ear that can “hear” radio frequencies far beyond the range of normal human capability.

“The design and implementation of bionic organs and devices that enhance human capabilities, known as cybernetics, has been an area of increasing scientific interest,” the researchers wrote in the article which appears in the scholarly journal Nano Letters. “This field has the potential to generate customized replacement parts for the human body, or even create organs containing capabilities beyond what human biology ordinarily provides.”

The finished ear consists of a coiled antenna inside a cartilage structure. Two wires lead from the base of the ear and wind around a helical “cochlea” — the part of the ear that senses sound — which can connect to electrodes. The ear in principle could be used to restore or enhance human hearing. Electrical signals produced by the ear could be connected to a patient’s nerve endings, similar to a hearing aid.

fuckyeahfluiddynamics:

Literature is full of descriptions of monstrous whirlpools like Charybdis, which threatens Homer’s Odysseus. While it’s not unusual to see a small free vortex in bodies of water, most people would chalk boat-swallowing maelstroms up to literary device. But it turns out that, while there may not be permanent Hollywood-style whirlpools, there are several places in the world where the local tides, currents, and topology combine to produce turbulence, dangerously vortical waters, and even standing vortices on a regular basis. 

One example is the Corryvreckan, between the islands of Jura and Scarba off Scotland. In this narrow strait, Atlantic currents are funneled down a deep hole and then thrust upward by a pinnacle of rock that rises some 170 m to only 30 m below the surface. The swift waters and unusual topology produce strong turbulence near the surface and whirlpools pop up throughout the strait. Other “permanent” maelstroms, such as those in Norway and Japan, arise from tidal interactions with similar structures rising from the sea floor.

For more, check out this Smithsonian article, Gjevik et al., Moe et al., and the videos linked above! (Photo credits: Manipula, Tokushima Gov’t, Wikimedia, and W. Baxter; requested by @kb8s)

psydoctor8:

Growing a Brain in a Dish  

That doughnut shape decorated with bright green spots, some connected by red pathways, amidst sky blue neighbors could be an artist’s creation, but is the result of a creative scientific attempt to grow an active brain in a dish, complete with memories. Really.
Researchers at the University of Pittsburgh published this stunning study in the journal Lab on a Chip {the full paper can be accessed here.} When I first learned how to grow cells in a lab, the technique of tissue culture, the idea of even growing brain cells was a far-fetched dream, much less brain cells capable of forming networks, complete with biological signals.

More from Dr. Jeffrey H. Toneye
Take that robots!

psydoctor8:

Growing a Brain in a Dish  

That doughnut shape decorated with bright green spots, some connected by red pathways, amidst sky blue neighbors could be an artist’s creation, but is the result of a creative scientific attempt to grow an active brain in a dish, complete with memories. Really.

Researchers at the University of Pittsburgh published this stunning study in the journal Lab on a Chip {the full paper can be accessed here.} When I first learned how to grow cells in a lab, the technique of tissue culture, the idea of even growing brain cells was a far-fetched dream, much less brain cells capable of forming networks, complete with biological signals.

More from Dr. Jeffrey H. Toneye

Take that robots!

— Neil deGrasse Tyson (via senoranelson)

(Source: anarchisthousewife)

yaleuniversity:

How do new arteries form after heart attacks, strokes and other acute illnesses?
Scientific collaborators from Yale School of Medicine and University College London (UCL) might have the answer. Learn more →

yaleuniversity:

How do new arteries form after heart attacks, strokes and other acute illnesses?

Scientific collaborators from Yale School of Medicine and University College London (UCL) might have the answer. Learn more

ikenbot:

The Current Types of Nebulae

Originally, the word “nebula” referred to almost any extended astronomical object (other than planets and comets). The etymological root of “nebula” means “cloud”. As is usual in astronomy, the old terminology survives in modern usage in sometimes confusing ways. We sometimes use the word “nebula” to refer to galaxies, various types of star clusters and various kinds of interstellar dust/gas clouds. More strictly speaking, the word “nebula” should be reserved for gas and dust clouds and not for groups of stars.

By order in which they appear from top to bottom, left to right, here are the main types and some provided examples for visual reference:

Planetary Nebulae: Sh2-188

Planetary nebulae are shells of gas thrown out by some stars near the end of their lives. Our Sun will probably evolve a planetary nebula in about 5 billion years. They have nothing at all to do with planets; the terminology was invented because they often look a little like planets in small telescopes. A typical planetary nebula is less than one light-year across.

Dark Nebulae: LDN 1622

Dark nebulae are clouds of dust which are simply blocking the light from whatever is behind. They are physically very similar to reflection nebulae; they look different only because of the geometry of the light source, the cloud and the Earth. Dark nebulae are also often seen in conjunction with reflection and emission nebulae. A typical diffuse nebula is a few hundred light-years across.

Emission Nebulae: NGC 896

Emission nebulae are clouds of high temperature gas. The atoms in the cloud are energized by ultraviolet light from a nearby star and emit radiation as they fall back into lower energy states (in much the same way as a neon light). These nebulae are usually red because the predominant emission line of hydrogen happens to be red (other colors are produced by other atoms, but hydrogen is by far the most abundant). Emission nebulae are usually the sites of recent and ongoing star formation.

Reflection Nebulae: NGC 1333

Reflection nebulae are clouds of dust which are simply reflecting the light of a nearby star or stars. Reflection nebulae are also usually sites of star formation. They are usually blue because the scattering is more efficient for blue light. Reflection nebulae and emission nebulae are often seen together and are sometimes both referred to as diffuse nebulae.

(Source: kenobi-wan-obi)

ikenbot:


Partial Lunar Eclipse

Mosaic of April partial lunar eclipse - first and last shot is approximatelly 75 minutes from mid-eclipse (penubral phase), central mosaic is made from shots captured every 2 minutes. Central image is from the maximum of eclipse (20:07 UT). The orange color of right part of mosaic is caused by low Moon above horizon. — Petr Horálek

ikenbot:

Partial Lunar Eclipse

Mosaic of April partial lunar eclipse - first and last shot is approximatelly 75 minutes from mid-eclipse (penubral phase), central mosaic is made from shots captured every 2 minutes. Central image is from the maximum of eclipse (20:07 UT). The orange color of right part of mosaic is caused by low Moon above horizon. — Petr Horálek

(Source: kenobi-wan-obi)