I think the cerebellum is one of the prettiest parts of the brain (for basic anatomy, go here). This is an image of the cerebellum showing purkinje cells in yellow and their outputs (axons that will take the information to the brain) in red. For more information about the cerebellum and purkinje cells, check out my post here. I love this image- all you can see is neurons, but you can see how compact they are on the outer layers of the tissue (just like cortex! They make up the gray matter.) and how the axons travel in the middle parts (just like the rest of the brain! They make up the white matter).
The cerebellum, its name meaning “little brain” in Latin, really does look like a smaller brain located just below the back of the occipital lobe. The cerebellum is often ignored in research (MRI researchers are especially guilty of ignoring activations back there). It seems to be involved in coordination and balance, but likely has other purposes as well.
In cross-section, the cerebellum itself looks like a tree, and the neurons inside of it (purkinje cells, named after the anatomist who first studied them) are definitely very tree-like. You can see the yellow neurons here have some big extensions like a tree trunk and then many, many branches off of them, just like trees do. It’s less obvious how very tree like they are in this image as they cover and overlap each other, but I thought this picture was beautiful nonetheless!
Researchers chose to test a simple kind of memory — a fear memory. In one experiment, mice were put in a chamber, allowed to explore, and given a foot shock. The next time the mice were put in the same dangerous chamber, they remembered the unpleasant electric shock and froze, taking on a defensive stance. Researchers had, however, inserted a gene that codes for a light-sensitive protein into the cells involved in making a memory. They then tested what happened when they turned on a light to activate those cells, without putting the mice in the same chamber. They saw the freezing behavior, as if the mice were reliving the memory.
“This is the most dramatic way to show that high cognitive phenomenon, like memory recall, can be generated, can be artificially generated by poking cells in the brain,” Tonegawa said in an interview.
He said there were about 20,000 neurons, or brain cells, involved in this particular kind of memory. [via]
I’ve seen a couple of these optogenetic experiments. It’s pretty fascinating to be able to manipulate the neural response in vivo.
We do some optogenetics in my research lab. It’s pretty awesome.
Stanford neuroscientists host the world’s first love competition, asking contestants between the ages of 10 and 75 to spend 5 minutes in an fMRI machine thinking deeply about the person they love. The results are certain to bring a tear to your eye.
Basically everybody dreams (unless there’s something really wrong with you), though some never remember their dreams. At any rate, dreaming usually occurs during REM sleep, which is short for “rapid eye movement.” Basically your eyes dart all over the place like you’re watching something, when you’re not. Like this baby is doing, in addition to being adorable.
Check out the graph above. This is what the average person’s sleep cycle is like. Awake is at the top, and then each category below that is increasingly deep levels of sleep. You will notice a few things about the graph:
There’s a rhythm to this sleep pattern. In the average person, one cycle takes about 90 minutes.
You have more deep sleep early in the night, and more light sleep, especially REM sleep, when it’s closer to morning.
Consequently, you dream more closer to morning.
Also, naps are awesome. Kayla’s nap tip: 60-minute naps are probably a bad idea. When you wake up from a nap, you want to have just been in a light stage of sleep. If you wake up during deep sleep, you’ll feel groggy and may be even more tired than before. See where the average person’s sleep cycle is after 1 hour? Yep, right in the middle of really deep sleep. Take naps in increments of 90 minutes, or keep them shorter than 30 minutes. (This is a generalization, and everyone’s sleep cycles are different. It’s possible that 60 minutes is perfect for you, but it’s not likely.)
[Picture: Background: 6 piece pie style color split with dark teal blue, and sky blue alternating. Foreground: A white lab rat with two visible arms and red eyes. Top text: “’I love you’” Bottom text: “’Aw, I experience a rush of dopamine and oxytocin with you, too’”]
A healthy human brain (left) compared to the brain of a 90 year old (right) which is only two thirds the size of the young brain. Over time, white matter decreases and the brain shrinks. This gradual shrinkage is most extreme between age 70 and 80.
Sometimes your brain plays tricks on you, and sometimes it flat out lies to you. Everything you sense, all of your sensory input, is interpreted by educated guessing. That’s right, your brain gets the information, takes it all into account, and decides the most probable “answer” to the “problem.” The McGurk effect is a great example. Based on the mouth movements, your brain decides the most probable sound you are hearing is “baa” or “faa.” But it is just an educated guess. (Not a bad guess! After all, usually when you see those lip movements, you hear the corresponding sound!)
The most popular illusions are, of course, optical illusions. Visual information is processed extensively by the brain, making educated guess after educated guess. Some illusions have been so highly studied that we know that the illusion is perceived in brain areas V2 and higher, but not in area V1. There are also a few auditory and tactile illusions, one of my favorites being the “velvet hand illusion.”
But don’t be mad at your brain for fooling you with all these illusions. It’s just doing the best job that it can to process the immense amount of information it is bombarded with every second. Besides, its methods are usually quite effective.
Okay, I just watched this thing where this little girl had half of her brain removed because her seizures were so bad.
And within weeks she was WALKING. FREAKING WALKING. WITH HALF OF HER BRAIN GONE. And her seizures were all gone.
The plasticity of children is so incredible. Her brain (the half LEFT in her head) learned so quickly to take over parts of what the removed part was doing. I mean, if you performed the same surgery on me I would probably never walk again. Completely paralyzed on half of my body.
Oh, and then there was this other boy with epilepsy who had some parts of his brain removed, but they had to do lots of tests to make sure they weren’t going to remove areas critical for language. And then they nonchalantly threw in the video, “Surgeons had to remove a small portion of the front of the brain in order to access the hippocampus.” And I’m like FRONTAL LOBE, WHY ARE YOU SO WEIRD?? Good thing it was only one hippocampus that was removed. Remove both of them and you’ll never form a memory again. Not exaggerating.
![neurolove:
I think the cerebellum is one of the prettiest parts of the brain (for basic anatomy, go here). This is an image of the cerebellum showing purkinje cells in yellow and their outputs (axons that will take the information to the brain) in red. For more information about the cerebellum and purkinje cells, check out my post here. I love this image- all you can see is neurons, but you can see how compact they are on the outer layers of the tissue (just like cortex! They make up the gray matter.) and how the axons travel in the middle parts (just like the rest of the brain! They make up the white matter).
[Image Source]](http://24.media.tumblr.com/tumblr_m2xnaefZXM1qb6etto1_1280.jpg)
![neurolove:
Cerebellar purkinje cells
The cerebellum, its name meaning “little brain” in Latin, really does look like a smaller brain located just below the back of the occipital lobe. The cerebellum is often ignored in research (MRI researchers are especially guilty of ignoring activations back there). It seems to be involved in coordination and balance, but likely has other purposes as well.
In cross-section, the cerebellum itself looks like a tree, and the neurons inside of it (purkinje cells, named after the anatomist who first studied them) are definitely very tree-like. You can see the yellow neurons here have some big extensions like a tree trunk and then many, many branches off of them, just like trees do. It’s less obvious how very tree like they are in this image as they cover and overlap each other, but I thought this picture was beautiful nonetheless!
[Image Source]
I LOVE THE CEREBELLUM. I love the whole brain, really. It is just so beautiful.](http://24.media.tumblr.com/tumblr_m2a2b2Qf7g1qb6etto1_1280.png)
![psydoctor8:
“MIT researchers turn on a memory”
Researchers chose to test a simple kind of memory — a fear memory. In one experiment, mice were put in a chamber, allowed to explore, and given a foot shock. The next time the mice were put in the same dangerous chamber, they remembered the unpleasant electric shock and froze, taking on a defensive stance. Researchers had, however, inserted a gene that codes for a light-sensitive protein into the cells involved in making a memory. They then tested what happened when they turned on a light to activate those cells, without putting the mice in the same chamber. They saw the freezing behavior, as if the mice were reliving the memory.
“This is the most dramatic way to show that high cognitive phenomenon, like memory recall, can be generated, can be artificially generated by poking cells in the brain,” Tonegawa said in an interview.
He said there were about 20,000 neurons, or brain cells, involved in this particular kind of memory. [via]
I’ve seen a couple of these optogenetic experiments. It’s pretty fascinating to be able to manipulate the neural response in vivo.
We do some optogenetics in my research lab. It’s pretty awesome.](http://25.media.tumblr.com/tumblr_m1m012mDUF1qan221o1_500.jpg)
![sweetandlovelygirl7:
psychologymajorrat:
[Picture: Background: 6 piece pie style color split with dark teal blue, and sky blue alternating. Foreground: A white lab rat with two visible arms and red eyes. Top text: “’I love you’” Bottom text: “’Aw, I experience a rush of dopamine and oxytocin with you, too’”]
because Valentine’s Day.](http://25.media.tumblr.com/tumblr_lhv4zgWkY61qhhwl3o1_400.jpg)
