sulcus

Structure/function: The Parietal Lobe

Behold! Your parietal lobe! You can thank this lobe for your ability to slap yourself in the face! You’re welcome!

Because it allows you to know where in space your hand is, where in space your face is, and where they are in relation to each other. Congratulations! If you have parietal lobe issues, you might have issues slapping yourself in the face… among other issues but those are probably not relevant.

More specifically, the parietal lobe is split up into the above sections. First you have the somatosensory cortex

(This post was brought to you by me, figuring out how to “remove background” on an image and abusing this newfound power). So with the hand slapping thing, you will feel both your hand making contact with your face, and your face being slapped, thanks to this doohickey!

The superior and supramarginal cortices are visual, so it guides your movement to, say, pick up a water bottle. And slap yourself in the face, although you can do that with your eyes closed (go ahead, try it). That’s thanks to the posterior cingulate gyrus but we will get there later because it is a LOT. For now we have the friendly, simple

Angular Gyrus, which does what it says. So thinking about your place in space, where you want to go, where you’ve been, which way is north, which way is your house. Boom. Angular Gyrus. The Angular Gyrus and the Supramarginal Gyrus together make up the inferior parietal lobule (sub-lobe)

Now on the OTHER side of the parietal cortex (cut your brain in half, saggitally, to expose this part) (don’t cut, like, YOUR brain in half… couldn’t learn much then, could you) (actually) (we won’t go there). Episodic memory retrieval=who, what, when, where, and emotions of memories.Makes sense this is with visuo-spatial imagery. When you imagine up these memories, you envision the location of these memories and where these memories took place. Self-consciousness is also related to this area (but not exclusively located here. It’s pretty well understood that’s not located in one area but processed throughout the brain. NOW for the REAL doosy

Phew. Look at that. And such a small area. It is primarily known for its role in the Dorsal Stream in visual processing. A lot of its other roles kind of relate to this, as it is also known as the “where” stream. So spacial awareness, movements in space, mental rotation (that skill on IQ tests where they give you the shape and ask you to ID the shape from another angle), mental imagery, manipulation of visual imagery. So your understanding and manipulation of space. Interestingly (possibly connected) math and reading abilities are also highly related to this area. Spatial and non-spatial working memory (temporary memory holding, decision making), response inhibition, and task switching are all related to this area. Which is interesting because they are also all related to the medial prefrontal cortex. Pathway?? (Probably, I haven’t looked into it)

Not labeled here:

Medial Parietal-Pain processing and meditation

Intraparietal Sulcus-Saccadic eye movements, attention, reaching, grasping, tactile manipulation of objects, observing hand movements, passive tool use, object matching and object size and orientation discrimination. (aka REALLY relevant for slapping yourself)

So there you have it. The overall structures and their functions within the parietal lobe! 

Cortical homunculus

I was asked to add more description to this image as someone told me “It’s cool, but I’m not quite sure what I’m looking at,” so here it is:

The image shows primary motor cortex and primary sensory cortex as if they were next to each other, which may be misleading. Both Motor and Sensory cortex run from one ear to the other and are present in both hemispheres. The way they are actually organized in space is that the Motor cortex is in front of the Sensory cortex. They are separated by Central Sulcus - a tiny gap that separates Frontal and Parietal Lobe. So the Motor cortex is anterior (towards the front of the brain) and is part of the Frontal lobe and the Sensory cortex is posterior (towards the back of the brain) of the Central Sulcus and is part of the Parietal lobe.

What’s called the Cortical Homunculus is the topographical representation of body parts in the cortex. And as one of my teachers say, this is not a representation as DaVinci would imagine it, but rather cubistic representation that Picasso might have come up with. Looking at the sensory cortex for example, we can see that closest to the centre of the brain (medially) is an area that processes sensations from the foot, and then more laterally (away from the centre) are areas processing stimuli from the rest of the leg, hip, trunk, arm and hand (notice how big the hand area is - important for perceiving subtle sensations and executing subtle hand movements), the neck and the head. 

The information from the body is processed in a contralateral manner - on the other side (e.g. sensations from your left foot are represented in your right hemisphere). A similar representation of the body can be seen in the motor cortex, where commands for deliberate movements are sent from to the various body parts.

The fact that there is a man on the left side on the motor cortex and a woman on the other side can be also confusing. Men have a representation of a male body and women of a female body.  

anonymous asked:

Hi! Is it possible for brain damage to cause lower-limb paralysis, or is that only ever damage to the spinal cord itself? And if someone did have a head injury that caused paralysis like that, what other side effects are they likely to have? (I assume paralysis isn't the only thing.) If it helps I'm specifically thinking of an injury caused by a car crash. Thank you!

Hey there nonny! If you’re looking for lower-limb paralysis exclusively, you’re looking in the wrong part of the anatomy.

Reason being this: the motor portion of the brain is kept in the prefrontal gyrus, just anterior to the central sulcus. It looketh like thus:

(source: excellent youtube video)

See that weirdly distorted “motor map”? that’s how your brain interprets your body, with different areas being different sizes based on how much of the brain they occupy.

Damage to this area will cause significant issues moving various body parts, but it won’t be isolated to the legs.

So if you want paralysis, a spinal cord injury really is the way to go.

Best of luck!!

xoxo, Aunt Scripty

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Cassini view of Enceladus, February 15, 2016

This image was taken during Cassini’s final close flyby of Enceladus. It captures Enceladus’ heavily fractured southern hemisphere from a distance of about 83,000 kilometers. Running left to right near the terminator is Cashmere Sulcus, and extending north towards the limb is Labtayt Sulcus. Mosul Sulcus is near the limb on the left. The south pole itself is in winter night.

Credit: NASA / JPL / SSI / Justin Cowart

youtube
  • central nervous system 中枢神経系 ちゅうすうしんけいけい
  • peripheral nervous system 末梢神経系 まっしょうしんけいけい
  • stroke 発作 ほっさ
  • Broca’s area ブローカ野 ぶろーかや
  • Broca’s aphasia ブローカ失語症 ぶろーかしつごしょう
  • brain のう
  • spinal cord 脊髄 せきずい
  • meninges 髄膜 ずいまく
  • cerebrospinal fluid 脳脊髄液 のうせきずいえき
  • neural tube 神経管 しんけいかん
  • prosencephalon or forebrain 前脳  ぜんのう
  • mesencephalon or midbrain 中脳 ちゅうのう
  • rhombencephalon or hindbrain 菱脳 りょうのう
  • telencephalon 終脳 しゅうのう
  • diencephalon or interbrain 間脳 かんのう
  • metencephalon 後脳 こうのう
  • myelencephalon 髄脳 ずいのう
  • brain stem 脳幹 のうかん
  • cerebellum 小脳 しょうのう
  • cerebral hemispheres 大脳半球 だいのうはんきゅう
  • cerebrum 大脳 だいのう
  • pons 脳橋 のうきょう or  きょう
  • medulla oblongata 延髄 えんずい
  • thalamus 視床 ししょう
  • epithalamus 視床上部 ししょうじょうぶ
  • hypothalamus 視床下部 ししょうかぶ
  • mammillary body 乳頭体  にゅうとうたい
  • limbic system 大脳辺縁系 だいのうへんえんけい or 辺縁系 へんえんけい
  • reptilian brain 爬虫類脳 はちゅうるいのう
  • cerebral cortex 大脳皮質 だいのうひしつ
  • gyrus  かい
  • sulcus 脳溝 のうこう or  みぞ
  • corpus callosum 脳梁 のうりょう
  • lobe よう
  • frontal lobe 前頭葉 ぜんとうよう
  • occipital lobe 後頭葉 こうとうよう
  • parietal lobe 頭頂葉 とうちょうよう
  • temporal lobe 側頭葉 そくとうよう
  • Wernicke’s area ウェルニッケ野 うぇるにっけや
  • hippocampus 海馬 かいば
  • amygdala 扁桃体 へんとうたい

anonymous asked:

How can i study anatomy before med school? Any tips?

I think the best way would be to do it in steps. Here is a 10 step suggestion on how to get more familiar with human anatomy:
1) learn all the name of the bones in the body, including the skull.
2) learn the name of the muscles on upper and lower extremities
3) go back to the bones and look at the structures: sulcus, fossas and so on.
4) learning the name of the 12 cranial nerves
5) look at the muscles of the face
6) look at the bony structures inside the skull: specifically pathways of the cranial
Nerves
7) axial skeleton & muscles
8) major organs and their position in the body
9) abdominal & pelvic muscles ++
10) look at the names of the major blood vessels & nerves

Basically having a look at these things and getting familiar with it (not learning everything by heart), will give you a better understanding of anatomy.

(Ps: left out joints, muscle attachments,detailed anatomy of organs, and some other things)

Hooked

Pairing: Dean x Reader (Female)

Word count: 904

My entry for  @torn-and-frayed Songs of Supernatural- Challenge.

This was so much fun!

Song: ‘Your Hooks On Me’ by Little Charlie and The Nightcats.

Warnings: SMUT-FLUFF.(Unprotected sex, this is only fiction! Always wrap it up!)


Dean looks down between them, to where their bodies are linked together, cock rigid, that big crooked vein traveling from his shaft to the sulcus under the head, popped up and throbbing.

Keep reading

5

After the Domhnall version you asked for Adam. So here are all the points I try to keep in mind when I’m drawing Adam. I put the explanations and analysis under a read more because it’s pretty long.

Kylo Ren is probably the easiest (well, compared to the others) character to draw. This is all thanks to Adam’s particular features that make him handsome to some and unforgettable to everyone. What is Adam’s face made of to be so particular you wanna ask?

Keep reading

Trimming Heels

Okay so heels are really, really important. Having a strong base of support under the leg is what keeps the bones aligned and keeps horses sound. Let’s take a look at what good heels look like:

Those heels are well under the leg and the appropriate length. Keeping them at an appropriate length is essential to having a 30 degree hairline, something that is a constant in all animals with hooves.

Now some bad heels. First, crushed and underrun. This means that the heels got too long but the wall was weak or exposed to severe concussion and the wall literally collapsed:

Then, simply long and forward:

And then just plain old high:

Heels can also be contracted (or too close together):

And they can also be sheared (or side swept):

Okay, so now let’s talk about actually trimming heels. There are some constants in the equine foot, and one of them is heel height. Now heel height varies based on the size of the horse, but it varies in small amounts because the coffin bone, no matter the size of the horse, does not get much taller or shorter than the average coffin bone. Here are the general heel heights:

Mini and Small ponies: ¾ inch

Medium and Large ponies: 1 inch

Average Horse regardless of weight: 1 1/8 inch

Drafts/Larger Breeds: 1 ½ inch

Club-foot capsules: generally add ¼ inch and reduce if the horse still weights the heel and stays comfortable

Obviously these are good guides, but not the rule. These measurements will achieve the 30 degree hairline, but if the horse is more comfortable with ¼ inch more heel height, that’s okay, particularly for the club-footed horses.

So where do you measure from? This is the best part! You measure from the hairline directly below the heel/collateral groove exit. The hairline is the most accurate sign of what is going on inside the foot, and measuring from there is the ONLY way to confirm that the heels are even relative to the internal structures. Sighting over the back of the heels is okay for an already in balance capsule or to make sure that the individual heel is flat, but for any kind of imbalanced capsule it will not work. Let me draw you an example from one of the hooves above.

Here’s what you would get out of this very deformed capsule if you just sighted over the heels to check them:

Check those purple lines. They aren’t even. One side of the hoof (the side that gets the least amount of wear from uneven loading) is still going to be jacked up. There is still going to be a medio-lateral imbalance.

How about if you measure from the hairline?

Ahh, that’s better! The joint alignment will be correct, and the hairline/lateral cartilages will finally get to relax down.

Just briefly, let’s talk about why these heels look this way. First of all, he’s been trimmed badly. Second of all, he weights his heel unevenly. Let me drive this point home: Heels do not grow at different rates, but they can be worn at different rates.

Okay so now that we understand how to properly measure them, let’s talk about actually trimming them. I like to measure the heels a couple times, marking the spot with a black marker. Usually, unless there’s just an astronomical amount of heel, I just use my rasp. The best way to trim a heel is to lay the rasp flat across it following the angle of the collateral groove and pull back towards you. It’s really important to keep the rasp flat. Your horse needs a flat landing surface. You want the “pointy” part of the heel to just touch the line you’ve drawn. I stop about ¼ inch away from the line on the heels, and then let the horse walk on them. I’m looking for comfort and proper weighting. There should not be an air gap between the heel and the ground. If the horse is happy with that height, and the foot is not clubbed, I will them go back and take the heel back to the baseline/correct height. Make sure that you have not made the heels lower than the quarters. You still need that air gap in the quarter for proper hoof mechanism.

After the heels are trimmed, it’s important to go back in and clean up the bars. They will usually mimic whatever is going on with the heels. If the heels are forward and underrun, there’s usually embedded/smeared bar on the sole. If the heels are tall, the bars are going to be even taller.

Here’s another important thing to note: it is OKAY to rasp into what looks like “live” sole in the seat of corn, even the quarters in some cases, if it is truly excess. I will post a link to Mike Savoldi’s article called “Uniform Sole Thickness” after this post. It’s an excellent read. This image is a good example of why is it important to not always assume that the sole you see is “sacred:”

Heels that aren’t getting enough wear or aren’t getting weighted will cause the hoof to fill in with excess sole, bar, and frog. The biggest clue that this is happening is collateral grooves that are unusually deep.

Okay, well how about contracted heels? Those are always caused by two factors 1. Imbalance and 2, disease. Balancing the hoof and treating the disease (usually in the central sulcus) and making the back of the foot more comfortable will spread out contracted heels.

Now, underrun heels are really interesting. Most traditional farriers will tell you that a horse with underrun heels has “no heel.” Well that’s not true at all! In fact, they have TOO MUCH heel. There are three important things to do when correcting underrun heels:

  1. Getting the heels to the right length from the hairline.
  2. Backing the toe so that breakover is correct in relation to P3
  3. Rim notching the wall tubules in the heel quarters

A rim notch is exactly what it sounds like: putting a notching in the rim edge of the hoof wall. Here’s a picture:

The hoof wall is removed no more than a centimeter high and through the white line. This DOES NOT make horses in lame if done properly. I only perform this technique once there is some relative stability and balance to the foot (after about the 3rd or 4th trim). This technique encourages the wall tubules to stop growing excessively forward and start growing down and parallel to the pastern angle. This will also encourage the heels to stand up, and I usually see some very rapid heel remodeling when this technique is applied.

Okay, I’m going to wrap this up with a cool hint that the hoof gives us about where the heel height should be. It’s the periople curl:

Dropping the heels to the green line (about where the periople skin starts to curl) would put this hoof at the correct angle. This isn’t usually reliable for a hoof that is extremely overgrown, but a lot of hooves it’s a good way to estimate.

PS sorry for typos i’m trying to buy a house and i’m tired

Tear in (Josh’s) Heart

“Which if you think about what love means, it means putting your needs before someone’s – their needs before your own.”

Crack one is made. It’s a small one, just over the right atrium. It barely splinters or spider webs, but it’s there and it cuts deeper than it looks. It just barely licks the right coronal artery, causing blood to seep out of the wound slowly, filling his chest cavity. It’s harder to breathe for a second, knowing that even though Tyler says that, he will never realize Josh does that every day of his life. He will never realize the love he holds for him.

 Josh talks and rambled on, describing love in an abstract way. He veers off into talking about his he would let them Tyler have the nice pillow. Tyler knows Josh does, and Josh confesses his love for Tyler. It’s not the first time, it won’t be the last. Tyler just keeps going, joking around.

He doesn’t know I mean it.

With that thought, the first crack spider webs into a second. It’s made right off the curve of crack one. It curls around the superior vena cava and pulmonary veins. His right lung is gone after that, cut off and only relying on his left for air. The aorta completely shredded, too. Its thin lines consume it completely, looking like a cobweb Cobwebs and flies come out that’s dripping blood over his heart the valves are severed and blood flow stops. Josh keeps joking, trying to stay afloat and keep his mind from wandering to thoughts of Tyler.  

“So Tyler, you just got married, right?”

Crack three stems from the bottom of crack one, enveloping the right ventricle. It squeezes it tight as he tries to cover up the pain and anxiety pooling inside him. He wonders for a second if anyone can hear the ripping sound of the muscle in his chest cavity, because he knows that he can. He can feel it, too.

“It’s a cover up for Josh and I’s relationship

Crack four is where his heart begins to splinter in two. A deep gash separates the right and left sides of his heart as his anterior intorvontricular sulcus rips, leaving cuts moving into his left ventricle from the crevice that was formed.  Josh laughs, hiding the hurt that Tyler jokes about what Josh dreams of.

“Now how do you- have you even stopped to think for a second about how this makes Josh feel?”

No. He didn’t. Tyler laughs about it as the interviewer goes on, joking too. It’s tiring, the way that he has to put up a joking front too. But Tyler has Jenna and he loves her and he’s happy with her. He doesn’t know what being blatantly serious would do to Tyler, but he does know it could ruin his happiness. Josh vows to himself to never do that. Josh buts in talking, and talks about how he thinks Jenna makes Tyler a better person and is good for his best friend. There’s a deep pang in his chest where the halves are becoming a gaping hole the more he talks. He knows he isn’t lying about what he’s saying, but is definitely jealous of it.

He wants to be in Jenna’s place, happily married to Tyler.

“When we first met, I had gotten this new app called Tinder. And I reached out and I saw Josh.”

Crack five is where his left ventricle is, the baby cuts from the fourth crack branching out like limbs of a tree. His great cardiac vein is slashed open from the growing tree. Josh laughs as his heart bleeds open Sometimes you’re gotta bleed to know, That you’re alive and have a soul, letting Tyler go off on their ‘how we met’ gag. He knows Tyler means it to make people laugh, so Josh locks away his feelings, leaving them for himself and his bleeding heart.

“You must have been jealous when he got married, right?”

Crack six. His frail, barely beating heart can’t take much more. Its left atrium is a mess of blood, the fluid pouring down like a waterfall. His left pulmonary veins are in tatters, and he can’t breathe anymore, his left and right lungs gone. Josh has to pause a moment before he can begin his attempted reply, Tyler talking too.

“Yeah, I don’t really-”

“It was a cover up for our-”

“I don’t want to talk about it.”

It hurts deep in his bones the way Tyler jokes about them having a secret relationship. The way he laughs at Josh not wanting to talk about it. Him and the interviewer think he’s playing with Tyler, but he really doesn’t want to talk about it. His jealousy is deep rooted in him, festering away at his insides, stemming from his slowly cracking heart. He keeps joking because if Tyler knew, he’d be upset and that’s the last thing Josh wants.

“A lot of people think this song is about Josh, but it’s not.”

(S)He’s a butcher with a smile. Cut me farther

Crack seven reminds Josh of a butcher the way he slaughters his heart. Slaughter’s his shriveled heart that’s only together because he promised to keep it beating for Tyler long ago. Won’t you stay alive, I’ll take you on a ride, I will make you believe you are lovely. The pulmonary trunk is as cobwebbed as his areola.  He pretends the “but today it is” fixes the wound.

It doesn’t.

Sometimes you gotta bleed to know, That you’re alive and have a soul, But it takes someone to come around, To show you how”

Josh barely feels crack eight shatter what’s left of him as he listened to Tyler sing on his phone, ear buds in as he lays in his bunk of the tour bus.

“She’s the tear in my heart, I’m alive, She’s the tear in my heart, I’m on fire, She’s the tear in my heart, Take me higher, Than I’ve ever been”

Tyler’s the tear in his heart; his broken, bloody, shriveled, ugly thing of a heart.

“The songs on the radio are okay, But my taste in music is your face, And it takes a song to come around, to show you how,”

All he knows is that he doesn’t want what’s left of his heart; he’d rip it out if he could.

“She’s the tear in my heart, I’m alive, She’s the tear in my heart, I’m on fire, She’s the tear in my heart, Take me higher, Than I’ve ever been”

It would probably hurt less than keeping it in.

“You fell asleep in my car I drove the whole time, But that’s okay I’ll just avoid the holes so you sleep fine. I’m driving here I sit, Cursing my government, For not using my taxes to fill holes with more cement.”

Josh can distantly feel tears rolling down his cheek as he curls up tighter under his blankets, turning up the music.

“You fell asleep in my car I drove the whole time, But that’s okay I’ll just avoid the holes so you sleep fine. I’m driving here I sit, Cursing my government, For not using my taxes to fill holes with more cement.”

Only six hours more and they’ll be onto their last venue of the Blurryface tour.

“Sometimes you’ve gotta bleed to know, oh, oh. That you’re alive and have a soul, oh, oh. But it takes someone to come around, to show you how,”

Josh plans to spend those six hours listening to Tear in My Heart on repeat on his music app.

“She’s the tear in my heart, I’m alive, She’s the tear in my heart, I’m on fire, She’s the tear in my heart, Take me higher, Than I’ve ever been”

He technically illegally downloaded his own music, because he wasn’t going to pay for something that he’d get the money for anyways, that’s dumb.

“My heart is my armor, She’s the tear in my heart, she’s a carver, she’s a butcher with a smile, cut me farther than I’ve ever been I’ve ever been I’ve ever been I’ve ever been”

He listens until he falsely believes that Tyler wrote it for him and was singing it to him.

“My heart is my armor, She’s the tear in my heart, she’s a carver, she’s a butcher with a smile, cut me farther than I’ve ever been I’ve ever been I’ve ever been I’ve ever been”

“I want to believe,” Josh whispers to himself, ready to go on pretending until Tyler truly leaves him once and for all. He closed his eyes and fell asleep to the song, as it started up again.

4

I used to really want to be a farrier when I was younger, but never pursued it since I’ve never been able to have a horse and always relied on my mom paying for riding lessons and (now that I’m an adult and she wont pay for my stuff anymore) riding friend’s horses.  But I would love to get into some barefoot trimming, probably only as a hobby of sorts until my back is not useless anymore.

So while I was cleaning up at the barn I work at, I took some pictures of Romeo’s hooves.  He’s lost 3 shoes (two fronts, and a hind) in the past few weeks - two of them in the span of a day.  The owner had the farrier out today to pull the remaining two shoes and is planning on leaving him barefoot.  Judging from his hooves and the other horses on the property, I think I can safely assume that their farrier is a very traditional one.  The majority of the horses are shod all the way around, long toes and heels, etc.

The bottom collage of four photos has the front hooves on top and hinds on the bottom.  Got a couple different angles since I wasn’t sure if my phone was going to focus correctly or not.  No good photos of the undersides since they’re caked in mud and gravel and I didn’t have time to clean them up.  I picked one of his hooves out and noticed that he’s definitely sore around the back of the frog and central sulcus (at least on the front left, but I wouldn’t doubt that it’s the same for all four).

Directing this post at barefoothooves (whose blog I spent several hours reading last night instead of doing laundry or cleaning) and anyone else who has some input!

Researchers Find Brain Area That Integrates Speech’s Rhythms

Duke and MIT scientists have discovered an area of the brain that is sensitive to the timing of speech, a crucial element of spoken language.

Timing matters to the structure of human speech. For example, phonemes are the shortest, most basic unit of speech and last an average of 30 to 60 milliseconds. By comparison, syllables take longer: 200 to 300 milliseconds. Most whole words are longer still.

To understand speech, the brain needs to somehow integrate this rapidly evolving information.

(Image credit)

The auditory system, like other sensory systems, likely takes shortcuts to cope with the onslaught of information – by, for example, sampling information in chunks similar in length to that of an average consonant or syllable, says study co-author Tobias Overath, an assistant research professor of psychology and neuroscience at Duke. The other corresponding author is Josh McDermott from MIT.

In a study appearing May 18 in the journal Nature Neuroscience, Overath and his collaborators cut recordings of foreign speech into short chunks ranging from 30 to 960 milliseconds in length, and then reassembled the pieces using a novel algorithm to create new sounds that the authors call ‘speech quilts’.

The shorter the pieces of the resulting speech quilts, the greater the disruption was to the original structure of the speech.

To measure the activity of neurons in real time, the scientists played speech quilts to study participants while scanning their brains in a functional magnetic resonance imaging machine. The team hypothesized that brain areas involved in speech processing would show larger responses to speech quilts made up of longer segments.

Indeed, a region of the brain called the superior temporal sulcus (STS) became highly active during the 480- and 960-millisecond quilts compared with the 30-millisecond quilts.

In contrast, other areas of the brain involved in processing sound did not change their response as a result of the differences in the sound quilts.

“That was pretty exciting. We knew we were onto something,” said Overath, who is a member of the Duke Institute for Brain Sciences

The superior temporal sulcus is known to integrate auditory and other sensory information. But no one has shown that the STS is sensitive to time structures in speech.

To rule out other explanations for the activation of the STS, the researchers tested numerous control sounds they created to mimic speech. One of the synthetic sounds they created shared the frequency of speech but lacked its rhythms. Another removed all the pitch from the speech. A third used environmental sounds.

They quilted each of these control stimuli, chopping them up in either 30- or 960-millisecond pieces and stitching them back together, before playing them to participants. The STS didn’t seem responsive to the quilting manipulation when it was applied to these control sounds.

“We really went to great lengths to be certain that the effect we were seeing in STS was due to speech-specific processing and not due to some other explanation, for example, pitch in the sound or it being a natural sound as opposed to some computer-generated sound,” Overath said.

The group plans to study whether the response in STS is similar for foreign speech that is phonetically much different than English, such as Mandarin, or quilts of familiar speech that is intelligible and has meaning. For familiar speech they might see stronger activation on the left side of the brain, which is thought to be dominant in processing language.

Because both hands are required to be equally active for pianists’ to master their instrument, they have to overcome something innate to almost every person: right or left-handedness.

In most people, the depth of the brain’s central sulcus is either deeper on the right or on the left side, which then determines which hand is dominant. But when scientists scanned the brains of pianists, they found something different: Pianists had a demonstrably more symmetrical central sulcus than everyone else — though they were born right or left-handed, their brains barely registered it. Because the pianists still had a dominant hand, researchers speculated that their equal depth was not natural, but resulted because pianists are able to strengthen their weaker side to more closely match their dominant side.
Researchers uncover "predictive neuron orchestra" behind looking and reaching movements

Different groups of neurons “predict” the body’s subsequent looking and reaching movements, suggesting an orchestration among distinct parts of the brain, a team of neuroscientists has found. The study enhances our understanding of the decision-making process, potentially offering insights into different forms of mental illness—afflictions in which this dynamic is typically impaired.

“Identifying which neurons are involved in looking and reaching actions means we can actually see them firing before these decisions are made, offering a crystal ball of sorts into subsequent movements,” said Bijan Pesaran, an associate professor at NYU’s Center for Neural Science, member of NYU’s Institute for the Interdisciplinary Study of Decision Making, and the study’s senior author.

It’s long been known that selecting and planning actions involve recruiting neurons across many areas of the brain. Specifically, it had been previously established that neurons in the lateral, or side, portion of the brain’s intraparietal sulcus (IPS) were active prior to eye movements while neurons on its medial bank fired before arm movements.

Less clear, however, is how ensembles of neurons work together to make decisions—such as eyeing a target, then reaching for it.

To address this question in their study, which appears in the journal Nature Neuroscience, the researchers examined different groups of neurons that were active ahead of a decision that involved discrete actions: eye movement and arm movement, or reach. This allowed the scientists to map an array of neuronal activity during two simultaneous actions.

In the study, primates engaged in a series of activities that involved both looking and reaching for different colored targets on a computer screen. During these tasks, the scientists recorded neurological activity in the IPS.

Here, they found “coherent” patterns of spike in activity among groups of neurons in both the lateral and medial regions of the IPS that predicted both eye and reaching movements. Other groups of neurons fired spikes without coherent patterns, and they did not predict the movements. The results, then, offered both a prediction of subsequent actions—based on preceding neuronal activity—and indicated an orchestration between these distinct sets of neurons.

“The timing of the spiking of these populations of neurons indicates they are working together ahead of a decision being made—apparently ‘sharing’ information before any overt action is taken,” observes Pesaran.

Cassini view of Enceladus, February 15, 2016 

This image was taken during Cassini’s final close flyby of Enceladus. It captures Enceladus’ heavily fractured southern hemisphere from a distance of about 83,000 km. Running left to right near the terminator is Cashmere Sulcus, and extending north towards the limb is Labtayt Sulcus. Mosul Sulcus is near the limb on the left. The south pole itself is in winter night.

image: NASA / JPL / SSI / Justin Cowart

(via: Planetary Society)