Stress and Anxiety, aka CRF and 5-HT2

Today’s post comes to you from several tweets that Sci received way back in the mists of time (that is…two weeks ago. Three? Something like that). Sci got wind of this paper and has been meaning to blog it for a while, but other things get in the way, like other things will. And when those other things finally get out of the way, Sci sometimes finds that she’s so SLEEPY she doesn’t know if she can make it through any more dry, sciency prose (sciency prose, even at the best of times, is pathetically dry. It’s why Sci blogs for you. See how she cares).
Like right now, when Sci is SO SLEEPY she just wants to lie down next to the cat and sack out. Scicat is currently reclining in a truly relaxed manner on the floor and isn’t making this any easier. But for the sake of stress, anxiety, depression, and a large glad of iced Moroccan mint green tea, SCI BLOGS ON.

(Sci’s determination very much resembles that of the bottom biting bug pictured here. A friend of mine showed this to me about a year ago, and it may still remain the oddest thing I have ever seen on the internet. Sci also finds it hilarious that every time anyone in Japan apparently trains for ANYTHING, they must at some point sit under a waterfall, and always end by looking determined on the top of Mt. Fuji. It’s like the Rocky Steps of Japan.)
Magalhaes, et al. “CRF receptor 1 regulates anxiety behavior via sensitization of 5-HT2 receptor signaling” Nature Neuroscience, 2010.

What does that MRI signal MEAN, anyway?

Sci was incredibly excited to see this paper come out. It’s got lots of stuff going for it, and all its powers combined were enough to send Sci bouncing around in her seat and sending emails to Ed Yong saying “OMG COOL PAPER!!”.
What’s it got, you say? It’s got the meaning of life, the universe, and that pesky MRI signal.
Lee et al. “Global and local fMRI signals driven by neurons defined optogenetically by type and wiring” Nature, 2010.

Ah, the pretty brain picture. But what does it MEAN?

Dopamine and Reward Prediction: What your brain looks like on Rickroll

Today Sci is going to blog a paper that she has been meaning to blog for a long time. It’s one of those papers that people who do certain kinds of science snuggle with when they go to sleep at night.

(Sci and this paper)
But the real reason that Sci loves this paper is that it’s the neurobiological equivilant of a RickRoll.

And the question behind this paper is: what is the mechanism behind reward prediction?
Schultz, Dayan, and Montague. “A neural substrate of prediction and reward” Science, 1997.

Is Mr. S more flexible than Sci? Cognitive flexibility and first-person shooter games.

This post comes to you courtesy, actually, of Sci-Dad, who sent an email to Sci saying wasn’t this cool. Sci then showed it to Mr. SiT, and he was very intrigued, and insisted she cover it. Sci kind of wanted to make cake balls. Maybe that will be tomorrow.

OM NOM NOM
Anyway.
Colzato et al. “DOOM’d to switch: superior cognitive flexibility in players of first person shooter games” Frontiers in Psychology, 2010.

(First, a brief tribute to Mr. SiT’s current favorite FPS “Battlefield: Bad Company 2”. Ever wonder how he passes the lonely hours while Sci is slaving away for your benefit? Now you know.)
Disclaimer: Sci doesn’t play video games. Neither is she a cognitive psychologist. Any errors in this post related to gaming may be firmly blamed on Mr. SiT, who read this thing first, and any errors in cognitive psychology can be firmly placed on Sci’s limited experience.)

Bulimia and the Vaso-Vagal Reflex

This is another post in Sci’s investigation into the current studies being performed on eating disorders, particularly binge eating and bulimia. Usually I try to focus on the dysregulation of reward-related systems in these disorders, but this paper will be a little different.
Faris et al. “De-Stabilization of the Positive Vago-Vagal Reflex in Bulimia Nervosa” Physiology and Behavior, 2008.
It’s kind of in the nature of an eating disorder that there aren’t any really funny pictures or something that Sci can put in here.
So before we go forward, here’s a kitten.

(ahhhhh.)

A Follow up: Depression, p21, CREB, and more

Everyone once in a while, someone sends Sci email. Often it’s silly. This one, however, was very good in that it asked for some clarification on a series of posts that I’ve been working on looking at clinical depression and possible causes and treatments, including neurogenesis in the hippocampus, cell cycle controls, and CREB.
And luckily, the guy who sent it gave Sci permission to repost, which is good, because it allows me to clarify some stuff. Here goes:

Hi Sci: I read your blog about how antidepressants stimulate neurogenesis in the hippocampus. Since the CREB deficient mice had robust neurogenesis and normal serotonin I wasn’t sure why they were anxious. Apparently they did benefit from antidepressants right away on the tail suspension and forced swim tests so the neurogenesis hypothesis took a bit of a whack. To add to the complexities I just read about MIF (macrophage migration inhibitory factor). Apparently reducing the amount of MIF in the rat hippocampus dramatically reduces neurogenesis and increases anxiety. Do you understand how CREB and MIF are related? I’m trying to get a handle on this whole complex area. Thanks.

All right, I’m going to try this before my first cup of coffee and we’ll see how it goes:

Cell Cycle p21, Depression, and Neurogenesis and in the Hippocampus

This is somewhat of a followup post. What’s really cool about this paper (to Sci, anyway), is that it brings two different areas that she’s been interested in into one cool glob of SCIENCE. And it helps to explain many of the questions that Sci got in response to two of the papers she has blogged about recently.
They are these:
1) The Incredible Healing Mouse: Bedelbeava et al. “Lack of p21 expression links cell cycle control and appendage regeneration in mice” Proceeding of the National Academy of Sciences, 2010.
2) The neurogenesis theory of depression and a little guy called CREB: Gur et al. “cAMP Response Element-Binding Protein Deficiency Allows for Increased Neurogenesis and a Rapid Onset of Antidepressant Response” The Journal of Neuroscience, 2007.
And NOW, behold their MUTANT OFFSPRING:

Pechnick et al. “p21 restricts neuronal proliferation in the subgranular zone of the dentate gyrus of the hippocampus” PNAS, 2008.
Well ok, technically it isn’t a mutant offspring, because this paper was BEFORE the first paper and after the second. So I guess it’s a stepchild. Or a sibling. Or just the results of how Sci was searching PubMed that day.
Anyway.
Let’s start with some background.

Book Review: Your Brain on Food: How Chemicals Control your Thoughts and Feelings

Sci recently got asked to be a book reviewer for Oxford University Press again! She is thrilled about this. Having recently moved to Huge New City (and consequently to Very Small New Apartment) she ended up having to…*gulp*…get rid of some books. It was a painful process, but she firmly believes her books are going to a good home (or at least the guys at the used bookstore started setting them aside into little piles with their names on them and begging Sci to return with more).

(*sniff* Goodbye, my lovely, lovely friends! Sci will miss you and think of you fondly! Go to a good home and don’t ever let anyone break your spine!)
But book reviewing is great! Sci gets more books! She can replenish her depleted supplies! Well. Ok. Very Small New Apartment probably can’t deal with much of that. We’ll see how far it gets.
Anyway, Sci was glancing through the list of books that Oxford sent along, and was immediately caught by this title:
“Your brain on food: how chemicals control your thoughts and feelings” by Gary L Wenk.
(Sorry there’s no pic, but Sci got a galley copy and doesn’t have the cover and can’t find it online. As an aside though, Much ❤ to Oxford Uni Press for BINDING their galley copies in little plastic covers with little plastic spines! YAY! Sci doesn't have to cart around a 400 page pile of paper! Other presses, take note. Your reviewers will LOVE you for this.)
Food! Chemicals! Brain! W00t! That's totally up Sci's alley. Sci pounced.
And so when the book arrived a few days later, I was very hopeful and opened it up first (oh yes, they sent a PILE, Sci's book shelves will soon be restored to their former glory).
And…well. See below.
Sci would like to note that writing this review gave her angst. So much angst that she ate most of a giant chocolate bar while she read it. I sacrifice my waistline for my art. Sigh…

On Washing your Fruit: ADHD and Pesticides

Sci was a little startled recently when she saw “the latest study” on ADHD splashed across the frontpage of Yahoo. You can see it here on Reuters.
PESTICIDES TIED TO ADHD.

(Run for the hills, indeed. Or maybe run AWAY from the hills, since they might have pesticides)
However, the story broke a good TWO DAYS in advance of the paper actually coming out, and so Sci was forced to possess her soul in patience until she had access.
But she’s got it now! And let’s take a look at this thing.
But first, I want us to all breathe in together and say: “Correlation is not causation”
Say it with me: “Correlation is not causation”

(Behold Sci contemplating the science of the universe)
All right, here we go.
Bouchard, et al. “Attention-Deficit/Hyperactivity Disorder and Urinary Metabolites of Organophosphate Pesticides” Pediatrics, 2010.

The Neurogenesis theory of depression and a little guy called CREB

Sci wishes she could begin this post with something clever. But she has a cold. Suffice it to say that this paper is cool and interesting. And also, as Sci has a cold, I expect all of you to read this post out loud to yourselves in suitably stuffy, gluey Sci-voices.

(*sniff*)
Gur et al. “cAMP Response Element-Binding Protein Deficiency Allows for Increased Neurogenesis and a Rapid Onset of Antidepressant Response” The Journal of Neuroscience, 2007.
(Yeah, yeah, the title is long and scary. Worry not, Sci will ‘splain.)
And this paper is especially good because it allows Sci to write a post on a topic she’s been meaning to get to even since she did a depression series way back when: the neurogenesis theory of antidepressant responses.
So here we go. And a new neuron is born.

(From Bumpy Brains. Sci thinks the rendition of diapers as glia is hilarious.)