vitamin for depression: 2012

Holiday Hiatus

If you have been wondering where new blog posts are, I am taking a holiday hiatus. I'll see you in January when biweekly posting will be resumed, and the cellular scale will celebrate its first birthday!

In the meantime, thank you for reading The Cellular Scale this year.

How to Lose Weight After Pregnancy While Breastfeeding?

(Getty Images)

Becoming a new mom is one of the greatest things in a woman’s life. But pregnancy also can bring more pounds of weight - therefore it’s reasonable if losing weight after pregnancy while breastfeeding is one of the most frequently asked questions after delivery. And did you know that your exciting moment of breastfeeding also can help lose your weight?

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Video game shooting vs Real shooting

Video game shooting is different from real shooting.

Battle Rifle, my Halo weapon of choice (source)

Sure playing video games (and therefore shooting in video games) releases dopamine, and sure if you inject dopamine into people while they shoot real guns they will like shooting guns better. BUT the key implication here, that shooting guns in video games makes you like shooting real guns demands evidence.

As a female Halo player myself, I think these Lady Spartans are awesome! (source)

Personally, I like shooter video games. I'm playing Halo 4 like the rest of the world right now and I played the heck out of Mass Effect earlier in the year. I have also shot real guns.

And guess what? shooting real guns is just not really my thing. I find it a little bit scary and not that fun or exciting. The idea of going to a shooting range and shooting guns at paper targets for an hour sounds really boring to me. Shooting skeet or something moving, like an animal, also sounds pretty boring.

I am skeptical about the idea that the dopamine released during shooting video games transfers to more enjoyment while shooting real guns. I am willing to change my mind upon seeing some data, but having seen nothing to support this direct transfer, I don't think it exists.

This post is written in response to "Addicted to the Bang: The neuroscience of the gun." by Steve Kotler and Jim Olds. (They don't actually claim that dopamine release during video game shooting directly causes addiction to real shooting, but I think that someone might get that idea from the article.)

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How to Build a Neuron: step 4

And now, the next step in neuron building! You can see all the previous steps and shortcuts here. Step 4 is adding intrinsic channels to your neuron.

Potassium Channel (source)

Pretty much all neurons need sodium and potassium channels so they can fire action potentials, but other channels such as calcium channels are also commonly seen in computational models.

To add these channels you have to extract the parameters from known data. This means extracting Boltzmann curves and time constant information so you can tell the channel which voltages activate it and inactivate it and how fast to open and close.

Activation (Boltzmann) curve for fast sodium channel

This step is tricky and can take a long time, but there is some software that can help. The Enguage Digitizer is one tool I could not live without.

Enguage is basically a tool that allows you to manually trace curves from published figures to get the curve data as an excel or .csv file. First you add axis points using the button at the top that has red plus signs on it. You tell the software what values each of the 3 corners of the graph are. Then you click the blue plus signs button and start to trace your graph, like so:

using Enguage digitizer to extract channel data

Then you export the data as whichever type of file you want. Pretty nice!
I like to have the data this way because then I can overlay this figure trace with any other trace I want and can manually fit an equation to it.

Channels are a hugely important part of a computational model. A recent paper from Eve Marder's lab shows that even with a very simple morphological model (just a soma), interesting electrical characteristics can be seen simply by manipulating the channels.

Kispersky et al., 2012 from Figure 1

Kispersky et al., (2012) introduce an interesting paradox. They show that when you increase the sodium channel conductance you see more action potentials with low current injections (like 200pA). This is expected because the sodium channel is what causes the upswing of the action potential and more sodium is thought to mean more excitability. However, the authors find that when a high current injection is given (like 10nA), the increased sodium channel conductance actually decreases the firing rate. This is counter-intuitive because it goes against the more sodium=more excitability rule.

This is a pretty cool finding published in the Journal of Neuroscience using only a simple one-compartment model. The finding is based entirely on channel manipulation, and demonstrates how important these intrinsic channels are to any computational model.

© TheCellularScale

ResearchBlogging.org

Kispersky TJ, Caplan JS, & Marder E (2012). Increase in sodium conductance decreases firing rate and gain in model neurons. The Journal of neuroscience : the official journal of the Society for Neuroscience, 32 (32), 10995-1004 PMID: 22875933

LMAYQ: seriously deep questions

And now, let me answer your Seriously Deep Questions. All questions answered can be found in the LMAYQ index. And as always these are real true search terms that the all-knowing Internet directed to The Cellular Scale. Let's begin.

Thoughts on grass (source)

1. "Do thoughts look like trees?"

Great question. Lots of things look like trees, certainly neurons do. But thoughts themselves?

It is my personal opinion that thoughts do not actually look like anything. I've dissected many a brain and haven't ever seen one. However, let's suppose thoughts look like something, what would they look like?

One possibility is that the thought looks like what you are thinking about. A pretty ancient idea is that there are actually two of every object, one that is external (the actual object), and one that is internal which is our representation of that object. This can be taken quite literally in which case if you are looking at or thinking about a tree, your thought will look like a tree, but if you are thinking about a dog, your thought will look like a dog. This strikes me as unlikely.

So another way to look at it is what does the brain look like when it is having a thought? In this case there is some support for the 'thought looks like what you are thinking' hypothesis, but it is very limited.

Do thoughts look like nets? (source)

Above is a famous example of how a visual stimulus can be reflected in the brain in a very literal way. In this case a monkey looks at a grid and the activation pattern in the brain looks like a grid. But these days 'thoughts' usually look like this:

thinking (source)

And there is no obvious or literal relationship between the shape of the fMRI image and the thought that is thunk.

2. "Why Neuroscience?"

Because neuroscience is our best chance at answering important questions like 'what do thoughts look like?' and 'How do we know what we know?'

3. "Do neurons tell you how to move or do they fire in response?"

Another excellent and deep question. The answer is (of course) that they do both.

People used to think of the brain as a black box, where sensory input comes in (like through your eyes) and gets 'processed' by the brain and a motor output comes out (like through your hands).

All of these steps, the sensory input, the motor output, and the processing in between take neurons.
But of course there is the Venus flytrap which doesn't have 'neurons' per se, but does receive sensory input and generate motor output.

But the processing part of this process, the black box, is really complicated. There really is an unanswered question there about whether neurons are responding to something or telling something. When studies find that mirror neurons fire 'in response to' seeing actions performed, or that some amygdala neurons fire in response to pictures of animals, the question is always why are these neurons firing? Are the neurons telling another part of the brain 'this is an animal'? or are the neurons responding to that information?

© TheCellularScale

Helping Someone with Depression During the Holiday Season and New Year

The holiday season is not just a time for traditional festivities, merry making, good will and celebrating with loved ones. For some, it's the loneliest time of the year. For others, sadness of missing a loved one or recovering from a life-changing trauma tinges the season. Many fall into despair as self-reflection takes hold, measuring the year's past accomplishment and failures. And then there are those who begin a downward spiral into the depths of a clinical depression.

My award-winning book "Living with Depression" offers tips and recommendations, as well as my own dual perspective of being a professional who specializes in depression and also being a person who lives successfully with this mental illness.

You can pick up the new paperback edition of "Living with Depression" online and in retail bookstores. Remember, depression is a serious, but treatable illness.

Cortical spine growth and learning how to eat pasta

There are two aspects to neuron shape. One is the pattern of dendritic or axonal branching, and the other is the pattern of spines. Spines are the little protrusions that come off of the dendrite often receiving synaptic inputs.

spines on a pyramidal neuron (source)

Because these spines are associated with excitatory synapses, and because synapse development is thought to be the cellular basis of learning, it makes sense that spines would grow when we learn.

But how would they grow exactly?

Using transcranial two-photon microscopy (a window into the brain of a living mouse), Fu et al. (2012) have caught images of neural learning in action.

A window into the mouse brain (source)

The authors used two learning tasks to investigate how spines grow during learning. In the "reaching" task, mice had to reach their paw into a slit and grab a seed. In the "capellini handling task" the mouse is given a 2.5 cm length of (I am not making this up) angel hair pasta and learns how to handle it for eating. learning is measured by how fast the mouse eats the pasta.

learning how to eat pasta makes mouse cortical spines grow (source)

They found that spines grow during learning (not too surprising). But spines also grow when the mouse is exposed to a motor-enriched environment (like a mouse-sized playground).

Fu et al. 2012 (Figure 2C+D)

The interesting difference between learning a specific task rather than just playing is that the spines grow in distinct clusters when the mice are taught a learning task. C shows the total spine growth, while D shows the proportion of clustered spines to total spines. Reach only means the mice were only taught the reaching task, and cross-training means they were taught both the reaching task and the pasta handling task.

The authors explain two possible functions for these spine clusters:

"Positioning multiple synapses between a pair of neurons in close proximity allows nonlinear summation of synaptic strength, and potentially increases the dynamic range of synaptic transmission well beyond what can be achieved by random positioning of the same number of synapses."

Meaning spines that are clustered and receive inputs from the same neuron have more power to influence the cell than spines further apart.

"Alternatively, clustered new spines may synapse with distinct (but presumably functionally related) presynaptic partners. In this case, they could potentially integrate inputs from different neurons nonlinearly and increase the circuit’s computational power. "

Meaning that maybe the spines don't receive input from the same neuron, but are clustered so they can integrate signals across neurons more powerfully.

And of course...

"Distinguishing between these two possibilities would probably require circuit reconstruction by electron microscopy following in vivo imaging to reveal the identities of presynaptic partners of newly formed spines."

More work is needed to figure out what is really going on.

© TheCellularScale

ResearchBlogging.org

Fu M, Yu X, Lu J, & Zuo Y (2012). Repetitive motor learning induces coordinated formation of clustered dendritic spines in vivo. Nature, 483 (7387), 92-5 PMID: 22343892

Back Pain During Pregnancy - How to Relieve It?

(Image credit to Shutterstock)

The good news, you will have a baby and she/he is growing which is something should be happening. In line with your pregnancy, your baby is growing in size but this is also the reason of why you will shoulder more pounds in your back. And this can put you at higher chance of having back pain. So, how to ease or relieve back pain while pregnant?

Before

Give someone 'the flu' for Christmas

Seriously.

The Flu (source)

I mean look at how cute that is. It's the perfect gift for the scientist or child of a scientist in your life.

And if you rather not give a stuffed flu microbe to your friends, how about 'beer yeast', or even the 'common cold'?

The Common Cold (source)

You can buy these and other plush giant microbes over at thinkgeek.

But giant microbes are not for everyone. Fortunately here is a Cellular guide to holiday gift giving:

For your more sophisticated science friends, perhaps some double-helix shelving.

DNA shelf (Tom Schneider)

Or maybe a lovely pyramidal neuron necklace. (I totally want this)

Pyramidal neuron necklace (Morphologica)

or a classy neuron tie.

neuron tie (Fractal Spin)

And something the whole family can enjoy.

Petri dish ornament (Artologica)

That's a start, if you know of any other great science gifts, feel free to add them in the comments.

© TheCellularScale

First Trimester Screening (Why and When – More FAQs)

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The first trimester screening is one of the most accurate methods of non-invasive screening – according to an article published in the New England Journal of Medicine (published on November 2005). According to this report, about 85 percent of babies with the chromosomal abnormalities are successful detected with this test. What else you should know?

Read also

Cramping While Pregnant in the First Trimester

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There are a lot of topics that we can explore when we are talking about pregnancy. And “Is it normal to experience cramp in the first trimester of pregnancy?”, -this is one of the most frequently asked questions, particularly if you are now being pregnant for the first time in your life. In general, cramping in the first trimester is normal, but how far it

Happiness Flow Chart

Simply shown

Not easily achieved

Nutrition for Early Pregnancy (First Trimester) – More FAQs!

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If you have a pregnancy for the first time in your life, you may have a lot of questions! Nutrition is one of the most frequently asked questions. But in general, you don’t need to pack in excessively extra calories in the first trimester of your early pregnancy. In other words, you may need additional calories but how much you should go? Then what are best

Growing 3D Cells

Neurons don't grow in a vacuum. They have white fibers, other neurons, blood vessels and all sorts of other obstacles to grow around.

Some NeuroArt (source)

A recent paper from France details the making of a 3D environment that can facilitate 'realistic' neural growth. Labour et al. (2012) created a collagen biomimetic matrix which contains neural growth factor (NGF).

Labour et al., (2012) Figure 3

These scanning electron microscope images show the porous fibril texture of the collagen matrix. Most of the paper is spent explaining the methods for making this biomimetic matrix, but they also actually grow some pseudo-neurons (PC-12 cells) on the matrix.

They show that when cultured on top of this collagen surface, the cells extend neurons in three dimensions into the matrices and are affected by the NGF. (when there is no NGF, the neurites don't grow and the cells die.)

This paper is mostly about the methods, but I like the new possibilities that growing 3D cells opens up. With these biomimetic collagen matrices, the factors that cause specific dendritic arborizations in three dimensions can be analyzed. The environment can be completely controlled and the neurons easily visualized during growth. The authors suggest using these matrices to study neurodegeneration as well.

Another interesting thing this paper introduced me to is the 'graphical abstract.' I didn't know that that was a thing, but it seems like a good idea. However, trying to summarize an entire paper in one figure seems pretty difficult. Here is their attempt:

Labour et al. (2012) graphical abstract

I think it does actually get the feel of the paper across pretty well, though it's not really informative without the actual abstract next to it.

© TheCellularScale

ResearchBlogging.org

Labour MN, Banc A, Tourrette A, Cunin F, Verdier JM, Devoisselle JM, Marcilhac A, & Belamie E (2012). Thick collagen-based 3D matrices including growth factors to induce neurite outgrowth. Acta biomaterialia, 8 (9), 3302-12 PMID: 22617741

Diet Tips to Ease PMS (Premenstrual Syndrome) Symptoms!

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There are a lot of advantages that we can get from a healthy and balanced diet. It can keep you beautiful, maintain your mood, keep the shape of your body (ideal in weight), and keep you active (more energy that you have every day). So what are healthiest and best foods for women of all ages, especially to ease symptoms of PMS? Keep reading!

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The ageless face of an Aes Sedai: Science Edition

How would the brain process a truly 'ageless' face?

Moraine, an ageless Aes Sedai (source)

I am sure this question has plagued many Wheel of Time fans, but only now has an experiment been designed to test it. Just 4 days ago, Homola et al. (2012) published a paper in PLoS ONE in which they have people guess ages of people in pictures and scan their brains.

Homola et al. (2012) Figure 1A. (Which one looks most Aes Sedai to you?)

The first interesting thing that they found was that the older the person in the picture (either a real picture of a real person, or a hybrid 'morphed' picture like the ones above), the harder it was to tell how old they were. This isn't really that surprising, as the range of ages that can 'look' a certain age gets wider over the years.

Homola et al., (2012) Figure 2B.

Here they plot the standard deviation in years for people's guesses as to the age.

The authors showed videos of the faces morphing from one age to another to volunteers while they were in the fMRI machine.

As a side note: they found that there was no difference between male and female volunteers. If they had I think a big deal would have been made about it. but since they didn't it's just a tiny sentence in a long paper.

Ok, back to the processing of age. They threw out the results from people who were really really bad at rating age because they 'weren't motivated' and weren't really trying apparently. (This could be a bit of cherry picking or data massaging) Then they compared the areas of the brain that were active for people who were really really good at guessing age, and people who were only average.

Homola et al., (2012) Figure 4D

The basic finding was that the posterior angular gyrus area (pANG) in the left hemisphere was 5 times more active for the expert age guessers than it was for average. Conclusion: pANG is important for age-processing. This on its own is good to know, but not amazingly interesting. What I think is cool is the idea that the authors present as a follow up experiment in their discussion:

"Even though our study highlights pANG as one key component for age processing, its precise role in this context is still speculative and needs further investigation. Our model, illustrated in Figure 7, gives rise to interesting hypotheses: One testable prediction would be that disruption of left pANG activity using transcranial magnetic stimulation (TMS), for example, should impair numerical age but not gender judgements, and that brain lesion-symptom mapping can eventually dissociate the two. " Homola et al., (2012)

So now we know, the Aes Sedai must have some magic that transcranially impairs pANG in everyone around them so they can't guess their age. That is how to stay truly ageless.

© TheCellularScale

ResearchBlogging.org

Homola GA, Jbabdi S, Beckmann CF, & Bartsch AJ (2012). A Brain Network Processing the Age of Faces PLoS One DOI: 10.1371

You Are Not Alone in this Fight: NAMI PSA

I am loving this short video from NAMI about heroes who lived with depression.

Reminds me of the video I made a few years ago highlighting over 400 high profile people who live with mental illness in my book "Living with Depression."

Healthy Sleep Cycle: How to Restore It?

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There are now a lot of factors that can disturb the cycle of your sleep. In this modern living, it’s important to keep your productivity. But sometimes, your tight schedule will put you at high risk of having lack of sleep. This can be the start for your sleep cycle to become irregular. So, how to restore and get back your healthy sleep cycle?

Before

Bladder Cancer - More FAQs You Should Know!

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As the name implies, bladder cancer is a kind of cancerous tumor (abnormal cells) that begins /occurs in the bladder. However, not all cases of this cancer are derived from the original cells of bladder. There are also a type called ‘secondary type’ - it is a cancer from other parts of the body (particularly nearby sites) that spread into bladder. In many

Bladder Cancer in Dogs (Symptoms, Causes, Treatment Options)

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Urethra, ureters, kidneys, prostate, and bladder are some important parts of the urinary tract. And cancerous tumor can occur in any of these organs /sites, but in many cases bladder is commonly affected. Invasive transitional cell carcinoma or TCC is the most common type of cancer that affects bladder in dogs.

Before continuing, you might also like to know

Virtual reality for your robot cockroach

I have previously covered some interesting advances in the world of cyborg insects.

Biobot backpack (cockroach size) (source)

Latif and Bozkurt from North Carolina state university recently presented a paper (though I can't find a peer-reviewed publication on Pubmed), explaining their Biobot. They use the Madacascar hissing cockroach...

Hissing Cockroach (source). Terrifying.

... and attach a electrically stimulating 'backpack' (see first picture). They then stimulate the the antennae in a variety of ways to 'steer' the Biobot.

"In these studies, electrical pulses were applied to the insect to create biomechanical or sensory perturbations in the locomotory control system to steer it in desired directions, similar to steering a horse with bridle and reins." -Latif and Bozkurt

This is very similar to the backyard brains Roboroach, but the system created by Latif and Bozkurt is extremely precise. Rather than just making the Biobot turn when stimulated, Latif and Bozkurt can make the cockroach walk a specified line.

Pretty cool. The authors note that generally the cockroaches want to walk straight until they encounter an obstacle (or stimulation). So, sure, this is sort of like steering a horse with reins, but the horse has to be trained to know what the bridle signals mean. This setup is more like creating a virtual reality for the cockroach, where it thinks that it has 'run into' something at certain points on the line. This is similar to creating a virtual reality for worms by stimulating specific neurons with light.

Of course the practical applications of this are a little iffy. People always seems to say that these little insect-bots could be of use in disaster settings where people need to get some ground level surveillance of a rubble-littered area, but I think the scientific applications for this are what is really exciting. Being able to create a virtual reality of any shape or size could allow for tests of spatial navigation in the cockroach. You could even try to train the cockroach to find something or avoid something and the 'confuse it' by changing the virtual environment suddenly. Could it adapt?

© TheCellularScale

Good News or the Bad News First? Why Taking the Hit Early Leads to Happiness

When it comes to living with depression, and you have a choice of taking good news or bad news first, research says to grab the bad news first. When both good and bad things happen, taking the pain so you can recover from it and the pleasure afterwards so you can savor it, leads to greater happiness.

Studies in happiness also show that happy people use positive social events, like meeting up with a close friend or talking with a cherished loved one after a bad experience.

Depressed individuals, however, tend to use positive monetary events like shopping or gambling as buffers against negative events, rather than social ones.

This study offers great insight into the everyday experience of how we choose to order painful and pleasurable experiences. For depressed people, take the bad first, then the good second, and make sure you surround yourself socially with others. This three-fold process will help you find greater well-being.

Resource: Sul, S.; Kim, J. & Choi, I. (2012). Subjective well-being and hedonic editing: How happy people maximize joint outcomes of loss and gain. Journal of Happiness Studies, DOI: 10.1007/s10902-012-9379-6

Treatment Options for Early Bladder Cancer

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Types, grades, and stages of bladder cancer are some crucial factors that greatly influence the kinds of treatment options to treat the disease. These factors usually also affect the prognosis and outlook of patient for survival. In general, an advanced cancer in the bladder is more difficult to treat than when it is diagnosed at early stage.

See also the

Suicide Survivor Awareness Day

Every year on the Saturday before Thanksgiving, the American Foundation for Suicide Prevention sponsors National Survivors of Suicide Day - reaching out to thousands of people who have lost a loved one to suicide. This Saturday, November 17th, is the 14th year of raising awareness and providing support.

Over 200 conferences for survivors of suicide will take place throughout the U.S. and across the world. Connecting on this day allows survivors to know that they're not alone in this experience.

To find a city worldwide where a conference is being held link here. Read more on suicide outreach and about the 10 common myths about suicide here

Every 40 seconds. someone dies by suicide. Every 41 seconds, someone is left to make sense of it.

How to Build a Neuron: step 3

Steps 1 and 2 of neuron-building, as well as an important set of shortcuts can be found in the How to Build a Neuron index. Step 3 is deciding which simulation software or programming language you want to use.

Simulated Neuron in Genesis (source)

The big two are Genesis and Neuron. They are pretty similar in a lot of ways, but Genesis runs in Linux and Neuron runs in Windows. However, you can run Genesis in Windows if you install the Linux environment Cygwin.

Both programs can read in morphological data, but they use different syntax and coding procedures. There are other types of neural simulators as well, and an ongoing problem in the field of computational neuroscience is compatibility between programs. If someone has done the work to make a beautiful Purkinje cell in Genesis like the one above, it will take a lot of time and effort to translate that neuron into a different simulator such as Neuron.

Gleeson et al., (2010) explains this problem and presents a possible solution in the form of the "Neuron Open Markup Language" or NeuroML.

"Computer modeling is becoming an increasingly valuable tool in the study of the complex interactions underlying the behavior of the brain. Software applications have been developed which make it easier to create models of neural networks as well as detailed models which replicate the electrical activity of individual neurons. The code formats used by each of these applications are generally incompatible however, making it difficult to exchange models and ideas between researchers....Creating a common, accessible model description format will expose more of the model details to the wider neuroscience community, thus increasing their quality and reliability, as for other Open Source software. NeuroML will also allow a greater “ecosystem” of tools to be developed for building, simulating and analyzing these complex neuronal systems." -Gleeson et al (2010) Author Summary

NeuroML is basically a "simulator-independent" neuronal description language. A neuron built with or converted to NeuroML should be able to run on Neuron, Genesis, and plenty of other platforms. Gleeson et al. validated NeuroML by using a simulated pyramidal neuron converted to NeuroML format and run with several different simulators.

Gleeson et al., (2010) Figure 7

Zooming in:

Neuron, Genesis, Moose, Psics comparison

All the simulators overlay so tightly that you can barely tell that they are separate lines.

So when building you neuron, take care to follow the NeuroML format and then you and others can use it with any simulator you want.

© TheCellularScale

ResearchBlogging.org

Gleeson P, Crook S, Cannon RC, Hines ML, Billings GO, Farinella M, Morse TM, Davison AP, Ray S, Bhalla US, Barnes SR, Dimitrova YD, & Silver RA (2010). NeuroML: a language for describing data driven models of neurons and networks with a high degree of biological detail. PLoS computational biology, 6 (6) PMID: 20585541

Stages of Bladder Cancer and Survival Rates

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All organs of our body are important, including bladder. It has important function to store urine (waste product of the body) produced by kidney. And cancer can significantly impair the function of this organ. The bladder cancer survival rates are closely associated with several factors, particularly the stages of the disease. What else you need to know?

You

Cut your brain some SLACK

Action potentials are the main means of communication between neurons, and their exact timing can be really important. But the specific timing of action potentials is really important in the auditory system, because the auditory system encodes (among other things) information about sound wave frequency.

Sound waves (source)

I've previously written about auditory processing with regards to the wonder that is the chicken brain, but today we will focus on timing-specificity in the mammalian brainstem. Specifically, some weird channels in the Medial Nucleus of the Trapezoid Body (the MNTB).

Mammalian Auditory Brainstem (source)

At the Society for Neuroscience meeting, I learned about the sodium-activated potassium channels which help the electric fish fire super-fast super-large action potentials. I was suprised to learn that sodium-activated potassium channels are located in many parts of the mammalian brain.

A paper from the Kaczmarek lab at Yale explains that these sodium-activated potassium channel (SLICK and SLACK) are present in the mouse auditory brainstem and contribute to the 'temporal accuracy' of the MNTB neurons. Yang et al. (2007) record the action potentials from these neurons at a range of frequencies and show that the neuron can 'keep' up with the frequencies better when more sodium is present.

Yang et al., 2007 Figure 9B

In the figure above, the 'flatter' the line, the better the 'temporal accuracy.' They also made a computational model of this neuron and ran simulations altering the sodium values and reversal potential.

Yang et al., 2007 Figure 9D

Their model simulations are similar to their experimental recordings, in that more sodium results in more temporal accuary of the action potential. They confirmed that this was dues to a sodium-activated potassium channel by directly activating SLACK and seeing a similar improvement in temporal accuracy.

The SLACK channel still blows my mind, but its role in helping the auditory system fire with the utmost precision actually makes a lot of sense.

© TheCellularScale

ResearchBlogging.org

Yang B, Desai R, & Kaczmarek LK (2007). Slack and Slick K(Na) channels regulate the accuracy of timing of auditory neurons. The Journal of neuroscience : the official journal of the Society for Neuroscience, 27 (10), 2617-27 PMID: 17344399

Children's Grief Awareness Day: 11/15/12

Grief is a powerful emotional experience that results from loss - be it from death, divorce, trauma or disaster. By the age of 16, over 5.4 million children will suffer the death of a parent, 50% of children will experience loss of a parent to divorce, and more than 68% of children will endure a traumatic event.

In an effort to bring awareness to this subject, Children's Grief Awareness Day is observed every year on the third Thursday of November. This awareness day helps bring light to the unique experience children have when losing someone they love - and an opportunity for all of us to recognize and support the millions of grieving children.

The National Alliance for Grieving Children offers some helpful facts about grief in childhood.

Grief is a normal reaction for a child to the death of someone in his or her life or a significant loss.
Grieving children can handle the truth, so be honest and open when talking about things.
Each child’s grief is as unique to him or her as was their relationship with the person lost.
Children who are grieving often feel alone and misunderstood.
Grieving children feel less alone when they can be with other children who have experienced the death of a parent or a similar loss.

Link here for tips on how to help your child or student deal with grief and here for more ways to comfort your child. And if these tools aren't helping to ease the pain, consider contacting a professional therapist who specializes in trauma and loss.