Neuroblogg

  A conglomeration. Neuroscience tidbits, videos, articles, and more!  

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Brain Map of Language

This brain map scientists at UC Berkeley developed certainly can’t help you if you happen to get lost inside your brain, but if you want to look at some interesting relationships between how and where the brain organizes language, you’ve come to the right place. 

The researchers, led by Alexander Huth and Jack Gallant, put seven people in an fMRI scanner and had them listen to a podcast called “The Moth Radio Hour.” After analyzing the scans and matching the timing of the transcripts of the show to the different brain regions that “lit up” during the fMRI scan, the group was able to create a brain map of language. This means they were able to “assign” different regions of the brain words that were consistently triggering a response from that region. The research is interesting because you can see that words we associate together such as: “killed,” “convicted,” “murdered,” and “confessed,” share the same region, above the ear, on the left side of the brain.

You can read the actual research paper here, and discover more connections in the map here.

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Brainbow

Neuroscience researchers have learned a thing or two from electricians, at least where Brainbow is concerned. You see, in order to figure out how different neurons interact with each other, scientists need to be able identify single neurons as they are going down twists and turns in the brain and body. And what better way to do that than by coloring them, as electricians have been doing with wires for decades? Brainbow does just that. It was developed by Jeff W. Lichtman and Joshua R. Sanes at Harvard, and it makes neurons in mice express different colors (around 90) using a genetic recombination method called Cre/lox, which shuffles DNA fragments. 

In fact, even the way Brainbow works is similar to the way the red, blue, and green pixels in a T.V produce many colors. Constructs, which are essentially packages of genes, are inserted into a neuron. These constructs can express one of four different fluorescent proteins (like green, cyan, or yellow) and the Cre/lox mechanism chooses which of the four colors is expressed through random DNA shuffling. In the end, each construct will express only one color. But since many constructs can be inserted into one neuron, you can get many different colors, just like a TV! 

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Neurotransmitters are chemicals that the nervous system uses to communicate, kind of like how the endocrine system uses hormones to communicate. Check out this graphic I made to learn about the really important neurotransmitters. 

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Amyotrophic Lateral Sclerosis 

It (usually) begins with a slight palpitation between the thumb and forefinger, and it’s all downhill from there.  Amyotrophic Lateral Sclerosis (ALS), or Lou Gehrig’s disease, is a neurodegenerative disease in which the motor neurons in the brain and spinal cord die out. This makes the muscles, starting with the ones in the hands and feet, weaken from lack of stimulation and the resulting disuse.  That slight palpitation in the hand is a sign of this motor neuron death.

As the disease progresses and more neurons die out and harden (sclerose), almost all of the muscles under voluntary control weaken, resulting in paralysis. But what’s really horrible about ALS is that since the mind is still intact, the patients become locked-in. They are trapped in their bodies while still fully aware of what is happening to them. What’s even worse is that these patients usually die by drowning in their own saliva (once their throat muscles are so paralyzed that they can’t swallow), or from respiratory disease (after all, the diaphragm is the largest muscle in the body).

There is currently no cure for ALS, but some research suggests that excess glutamate is a contributor to the disease, so anti-glutamate drugs like Riluzole can slow down its progression. ALS research is in deep need for more funding and attention. Check out the ALS Association’s website for more information on ALS and to donate if you are so inclined.

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The Vastness of Neurology 

I came across this quote by Dr. Raymond Adams while reading Reaching Down the Rabbit Hole by neurologist Allan Ropper, and I wanted to share it. I’d always known that neurology was a big field, but I’d never realized just how big it was. No wonder there’s so much we don’t know about the brain and nervous system. This is some great food for thought. 

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Cone Trickery

Everything we see is in our heads. And this video of cone trickery by Guillaume Riesen shows just that(it also never fails to amuse me).Try it! If you just want to see the trickery and read my explanation(although you should definitely listen to Guillaume’s wonderful explanation) below, you can skip to 2:29. You’ll see that after looking at a red cross on a picture with inverted colors, the same picture in black and white will appear to be normally colored. 

This trick works because there are receptors on your retina(at the back of the eye) called cones which allow you to see color, and they get tired. But let’s backtrack a little. We have 3 types of cones which let us see different degrees of red, green, and blue. So when we look at something red like an apple, our red cones are active and the blue and green cones are “resting.” But if we stare at something red for too long, like the red cross and the inverted image in the video, the red cones will become fatigued and the blue and green cones will take over. Since we only see white when all of our cones are equally active, and our red cones have become fatigued, the blue and green cones take over once we switch to the black and white image and it seams to be a colored imaged with different shades of blue and green. Pretty cool isn’t it?

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See Your Own  Action Potentials

Meet my muscle action potentials. Action potentials are the changes in the charge of the inner and outer  membrane of your muscle fibers which allow your muscles to contract. And for only around $80, you can see yours too! Here’s how, but first, a little background.

 In the milliseconds it takes to contract your muscles, your brain orchestrates a series of events that allow you to contract your muscles. First, neurons in the motor cortex of the brain, which extend along your spinal cord, synapse, or make a connection, with lower motor neurons in the spinal cord. These motor neurons then synapse with muscle fibers and fire an action potential which causes the release of the neurotransmitter acetylcholine into the synapse (“Synapse” can be used as a verb or noun: “to synapse” is to make a connection and a “synapse” is the junction between two neurons or a neuron and a muscle fiber). The acetylcholine causes a change in the charge of the inner and outer membranes of the muscle fiber and can cause it to make its own action potential (if a certain threshold is met), resulting in a twitch. Many muscle twitches result in a muscle contraction. Since all of this is just electricity, you can look at your own action potentials using what is known as a bioamplifier.

This lab is heavily inspired by the Backyard Brains “Getting started with the EMG SpikerBox” lab. However, instead of using the Backyard Brains SpikerBox bundle, I found a cheaper alternative: a combination of an Arduino Uno and an Olimex EMG shield which work together as a bioamplifier.

Theory:

More detailed theory for this lab can be found under the "background" heading in the Backyard Brains EMG SpikerBox lab.

Materials:

Arduino Uno

Olimex EMG shield

USB cable

3 Electrode cables ( I made my own by soldering 3 alligator clip test lead cables to a 3.5mm plug, but you can purchase ready made cables from the link if you prefer)

3 Electrode patches

Computer/laptop

Software and Code:

For information on how to set up your arduino uno and download its drivers, visit the arduino website.

You can find all the Olimex EMG shield user guide, arduino EMG code, and download the Electric guru software from the Olimex EMG shield website.

1. Set up your arduino and download its drivers. The arduino will recieve electrical information from your muscles through the EMG shield and electrodes. And using the code, you will be able to see your own actual action potentials in a program called Electric guru.

2. Download the Electric guru program.

3. Download the arduino EMG code (it’s labeled as EKG but it also works for EMG).

Procedure:

1. Attach the muscle shield to the arduino (they fit on top of each other) and connect the arduino to your computer using a usb cable.

2. Place 2 electrode patches on your biceps (upper arm). One towards the top of your biceps and the other towards the bottom. You need these two electrode patches because the EMG recordings display the potential difference between two seperate electrodes. 

3. Place the third electrode on your elbow. This will serve as the ground, or reference electrode.

4. Connect each electrode patch to an electrode cable and connect the cable to the muscle shield. 

5. Connect the arduino to your computer and start up the Electric Guru program.

6. Once you have opened up the program, go to preferences -> Trace and make sure that both channels are on because the program will display the result from the potential difference between the two electrodes on you biceps.

7. Click start. You should see straight, slightly squiggly lines. But once you contract your muscles, you should see the muscle spikes because your muscle contractions result from action potentials. Keep in mind that since the electrodes are reading from your biceps, the muscle spikes you see are from 100s of muscle fibers, because the biceps contain many muscle fibers.

Congratulations! You have just seen your own muscle spikes. 

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(via Meet the Neuroscientist Who Installed an Implant in His Own Brain | MIT Technology Review)

Philip Kennedy

I thought it was cool when MIT Professor Nancy Kanwisher shaved her head to teach an anatomy lesson, but neurologist Phil Kennedy certainly blew her out of the park. Kennedy is one of the fathers of “brain-computer interface.” Basically, that means that he pioneered a really invasive surgery that connects electrodes in a human brain to a computer. This allows the computer to receive information from the brain, which depends on electricity for communication. And when Kennedy couldn’t get enough data for his project, a speech recorder that would take neuronal signals produced when you imagine speech and convert them into words “spoken” from a speech synthesizer, he had brain surgery in Central America in order to collect more data for his dying project. After his surgery, which is his in more ways than one because he pioneered the surgery, Kennedy went back to his speech lab and experimented on himself to get more data. And he did. He even had enough data (from his brain of course) to present his findings at the Society for Neuroscience! To find out more check out this great article by the MIT Technology Review.

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The Connectome Revisited

World, meet the connectome. Connectome, meet the world.

I’ve talked about the connectome many times here, but I wanted to re-post this infographic I made a while ago because it was my first post on the blog. The connectome is essentially the genome, but on steroids, and for the brain. It’s the  attempt to map the connections between each of the connection points, or synapses, between neurons. Such a map would be very beneficial to scientists in learning more about how we are who we are. The Seung Lab is doing a lot of awesome work on the connectome. You should definitely check out Sebastian Seung’s TED talk on the connectome for more juicy details and even read his book, “Connectome:How the Brain's Wiring Makes Us Who We Are” if you are so inclined. I highly recommend it. His Lab even developed Eyewire, a  “game to map the brain!”

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Motor Neurons...for Real

This is a picture I took of motor neurons using my phone camera and a microscope at 100X magnification. Besides the fact that they look cool, motor neurons are the neurons responsible for sending the “contract” signal from your brain or spinal cord to your muscles so that they can contract. To find out how exactly this happens, check out this Khan Academy video.

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Source: Jason

Backyard Brains

This is a really cool project that’s been around for a couple of years, but I’ve just recently heard about it. It’s basically DIY neuroscience that almost anyone can do. The co-founders, Greg Gage and Tim Marzullo, started “Backyard Brains” while they were studying neuroscience in grad school. They wanted to get more people interested in neuroscience and they knew that the reason more people weren’t interested in the brain because neuroscience equipment is very expensive and inaccessible. So they started with a prototype for the spikerbox, a device that allows you to hear neurons firing and even see neuronal spikes (basically action potentials) on a free app they created, and they received so much interest from scientists at the convention they presented it at that they decided to take their project further, and Backyard brains was born. Check out their website. There, you can buy the spikerbox assembled or as a kit to build yourself and also explore their many experiments using the spikerbox. My favorite one is controlling someone else’s arm while learning principles of neural prosthetics.

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Brain Unveiled 

MIT Neuroscientist, Nancy Kanwisher, shaved her head and had someone draw on it, to teach a short lesson on neuroanatomy and introduce her research on finding out what different parts of the brain might doing using fMRI technology. Check out this video to see her shave her head and give the lesson! Also, this is a link to her other videos.

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Toxoplasma Gondii

Meet toxoplasma gondii. Well actually, you probably don’t want to meet it. Toxoplasma is a parasite that can infect almost all warm blooded animals, humans included. It’s interesting because scientists have found an association between it and neurological disorders, namely schizophrenia. In one study, women with high levels of toxoplasma were more likely to give birth to schizophrenic babies. This is because toxoplasma is thought to affect behavior and neurotransmitter function. In fact, mice infected with this parasite became fearless and were attracted to cats (thus leading to their death) because toxoplasma affects brain regions responsible for fear. Pretty interesting isn’t it?. Check out this Scientific American article for more details.

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Zombie Neuroscience

This video is  pretty funny and it takes a unique approach to teaching about the brain. It explores different neuroscience concepts by hypothesizing what could be wrong in the brains of zombies. You’ll learn about Parkinson’s disease, the neurotransmitter dopamine, ataxia, the cerebellum, Broca’s aphasia, Wernicke’s aphasia, and the arcuate fasciculus and how all of these relate to Zombies. But here’s a quick list of the definitions of the terms for your reference:

Dopamine: a neurotransmitter found in the basal ganglia in the brain. It’s associated with movement.

Parkinson’s Disease: a disease in which the dopamine releasing neurons of the basal ganglia die off, resulting in difficulty in movement and muscle rigidity.

Ataxia: inability or lack of movement of the voluntary muscles.It’s usually a result of the dysfunction of the cerebellum- the little brain.

Broca’s aphasia: inability to produce coherent speech.

Wernicke’s aphasia: inability to comprehend language.

Arcuate Fasiculus: Bundle of neurons that connects Broca’s area (in the frontal lobe) to Wernicke’s area (in the temporal lobe).

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Genes and the Placebo Effect 

You know the phenomenon in which a “sugar pill” or fake treatment can alleviate a person’s sickness if he or she is convinced that the placebo is real (they don’t know it’s a placebo). But while I was doing some research on the placebo effect, I happened upon this interesting article on Business Insider that indicates that there’s a lot more we don’t know about the already mysterious placebo effect. The article discusses the theory that certain genes make people more susceptible to the placebo effect. This theory came about because in a trial, when people with a high dopamine variant of the gene that regulates the amount of dopamine in the brain, COMT, were given a placebo, they were more likely to feel improvement than people without the high dopamine variant of the gene who also received the placebo. Of course, this is just a correlation. And correlation does not imply causation. But it’s still interesting to think about. Check out the article for more details.

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Memory

Have you ever wondered which parts of your brain process your memories? Well check out this graphic I made to find out the basics.

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Second Brain

We all know about our first brain in our heads. But did you know that you have a “second brain?” It’s a mass of nerves in your digestive tract called the enteric nervous system. It’s not responsible for higher thought processes, but it does work with the “big brain” to determine your mental state- that’s why you get “butterflies” in your stomach. The second brain can work independently of the big brain, and it also has lots of neurotransmitters, over 30 different types, like the big brain does. In fact, it has 95% of the body’s serotonin. And interestingly enough, SSRIs (Selective Serotonin Reuptake inhibitors) which are antidepressants that increases serotonin levels, can cause digestive tract problems... 

Food for thought...pun intended. Check out this Scientific American article for more details.