Archive for: December, 2011

Holiday Chickens

Dec 26 2011 Published by under Uncategorized

Despite my carefully crafted holiday gift guide, I instead received this:

It's not totally random. A few years back we were driving in Maine and pulled into an old antique store. You know the type: an old barn stuffed with all sorts of old junk, from dusty accordions, to cast iron skillets to discarded taxidermy. In this store I saw this beautiful stuffed chicken which I totally wanted to get, but somehow I ended up not doing it and have regretted it since. Thus, supercool wife decided to, well, get me a taxidermy chicken.

He now resides in my office to keep me company. I can't wait until the students come back and start complaining about their grades. Then I can just lift up my hand and say "Nope, go tell it to the bird..."

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A Neuroscience Field Guide: Vagusstoff

Dec 21 2011 Published by under Uncategorized

Vaguwhaa?? Vagusstoff literally means "stuff from the vagus nerve". This is from the days where scientists gave things really imaginative names, and if you were German, you could combine several words to come up with some official sounding term like "Bitsöfbraininajähr". But back to Vagusstoff. Vagusstoff (make sure you use a strong Germanic pronunciation when saying it) is actually the neurotransmitter acetylcholine, before it was known to be acetylcholine, or rather when it was thought to be something else.

Back in the early days of neuroscience, like in the 1920's, folks already knew electrical impulses formed the basis of signaling in the nervous system. But there was some debate whether chemicals might also mediate part of this signaling. This was the start of what later became the "war of the soups vs. the sparks". The soup camp favored a chemical mode of communication between brain cells, while the spark camp said neurons were electrically coupled to each other. Enter physiologist Otto Loewi.  Loewi had been preoccupied by a specific question about how the heart worked.  The heart is innervated by two main nerves, the vagus nerve and the sympathetic nerve. If you activate the sympathetic nerve, the heart rate accelerates, but if you activate the vagus, then the heart rate slows. What was puzzling to him was that if both nerves were electrically coupled to the heart, how could they lead to opposite effects? Perhaps, he thought, the nerves are releasing some "stuff" that then differentially modulates the heart rate.

Loewi designed the following experiment. He took a frog heart and kept it in a chamber with media. Then he stimulated the shit out of the vagus nerve using a series of electric shocks. This caused the heart rate to slow. He took a second frog heart in another chamber, and this heart was denervated (ie. had both nerves removed). He then extracted some media surrounding the first heart and added it to the chamber containing the denervated heart. If a chemical was released by the vagus which caused the heart to slow, then this chemical should be present in the media around the heart and should also cause slowing of the second heart. And that is exactly what happened, when he added media from the stimulated heart to the chamber containing the second heart, the second heart also slowed, confirming his hypothesis. Since he couldn't come up with a better name for this stuff released by the vagus, he called it Vagusstoff.

Loewi did several variants of the same experiment and published his findings in 1921 in a paper entitled "Über humorale Übertragbarkeit der Herznervenwirkung. I." Fun stuff. Anyway, Vagusstoff turned out to be the same thing as a chemical previously discovered by pharmacologist Sir Henry Dale which was known as acetylcholine. It also turned out that the stuff leaking out of the sympathetic nerve was the neurotransmitter norepinephrine. Thanks to Loewi's experiments it was finally accepted that communication between neurons could be chemical, and both shared a Nobel prize in 1936. The war of the soups and sparks raged on for several years, and when the dust settled it turned out that the nervous system contains both chemical and electrical synapses, but that's another story.

Acetylcholine

Speaking of stories, there's a crazy one about Loewi. According to neuroscience lore, Loewi first had his idea for his experiment in the middle of the night in a dream. But after he went back to sleep and awoke the next morning, he forgot what the stupid experiment was supposed to be. The next night he had the same dream and this time he rose in the middle of the night and ran to the lab in his pajamas to extract some frog hearts. By the morning he had discovered synaptic transmission.

So the lesson? I'm not sure. Something about going to the lab in your pajamas — or something.

 

Further Reading

Otto Loewi's Nobel Lecture.

Sir Henry Dale's Nobel Lecture.

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Gift guide!

Dec 05 2011 Published by under Uncategorized

So the holidays are rapidly approaching! And you have no idea what gifts to give your loved ones. Neither do I, but I do have an idea of the kinds of gifts I'd like to receive (hint, hint). So here it is, the first ever, Take it to the Bridge's holiday (or year-round) gift guide!!

Purkinje Cell - G.Dunn

Pencils

I love pencils. I think they make the ideal writing/drawing implement and love the feel of them on the page, especially soft dark pencils. Plus I always feel I take better notes and write better outlines when using pencil. I would be happy with a box of 4B Palominos. I also hear that their revived Blackwing 602's are nifty. That should keep me well stocked for the upcoming grant and manuscript writing season. Also, if you're into pens and other writing implement also be sure to check out this other awesome online store that sells Japanese writing implements.

Paper

Of course a nice pencil deserves nice paper. I love taking notes on graph paper, reminds me of my pimply-teen D&D playing phase. These French note pads are silky smooth and cool looking. I've never tried the notebooks, but they look like they have potential.

Cajal

I've been lusting for this book, "Cajal's Butterflies of the Soul", since I saw it at the Society for Neuroscience meeting. I didn't buy it because  I didn't feel like lugging it around the convention center or carrying it all the way back home (its a big book). I reproduces amazing hand-drawn images of neurons from the 19th and early 20th century. It is beautifully produced and a joy to look at.

Big Neurons

This dude, Greg Dunn, is a neuroscience graduate student who makes beautiful large-scale paintings of neurons in his spare time (grad students have spare time?).  He usues a style that reminds me of traditional Asian painting. The paintings seem to be by commission but he also sells prints. Maybe I'll get some pyramidal cells for my office.

Typewriter

Not sure why I want this. But wouldn't it be fun to have a nice refurbished manual typewriter to mess around with? Every time I write using a different medium I come up with different ideas and perspectives. This would just add to the mix. Plus I think my daughter would also get a kick out of this.

Model Rockets

I'm not sure these are even legal in my state, but I've had this urge to assemble some model rockets and fire them off. We used to do this when I was a kid (we being my cousins and I) and had a lot of fun. I remember spending weeks carefully assembling and decorating them, and then losing half of them, especially when we retrofitted them with a much to0-large fuel cylinders. Somehow they seem to have  lost popularity, or maybe not, I just don't amble upon those circles any more.

Paper Craft

A few years ago I saw these little Japanese kits to make robots out of paper. The kind you cut, build, glue and assemble. They seemed a bit pricy and somehow I didn't get them. But then recently I saw a whole book with a bunch of little monsters you could cut, and assemble, each cooler than the last. I didn't buy it because my kids were screaming about one thing or another, and in the chaos I left the store without buying it.

SpikerBox

OK, so I already have one of these, but it would make a great gift if I didn't. I bought one of these amplifiers that allow you to record neural signals from cockroach legs (and maybe from other critters) for one of my classes, and the activity was a big hit. The maker, Backyard Brains, are always working to improve their boxes and come up with new experiments.

Strumstick

No, it's not what it sounds like. A strumstick is a stringed musical instrument apparently similar to a mountain dulcimer. The frets are set such that it only plays a major scale, and it only has three strings. So if you press any fret on any string, you will always generate a pleasing sound when you strum all three strings, so no matter what you do, it always sounds cool. It looks like it would be a lot of fun to play.

Coffe Crisps

Canadians do a lot of things right. But the best thing they've got going for them are the awesomest candy bar known as a Coffee Crisp. Imagine a Kit Kat on steroids and dunked in a cup of espresso. That's a Coffe Crisp. Light, airy, crunchy and coffee-y chocolate. Everyone I know has a standing order that if they ever go to Canada they must return with Coffee Crisps.

Boomerang

Why the hell not? Wouldn't you like to learn to throw a boomerang? Just make sure its a lefty one.

So there you have it. Now you know what gift to give me... if you ever feel so compelled. What kinds of things do you like?

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