neuroscience
clock | June 25, 2006The Synapse, new carnival of neuroscience - from molecules to cognition and everything in-between - is the first carnival that originated here on SEED scienceblogs.com. Today, the first edition saw the light of day, so you should go over to Pure Pedantry to check it out. The homepage of the carnival, with archives, instructions for submission, etc., can be found here.
In two weeks, on July 9th, 2006, the carnival will be held here, on A Blog Around The Clock. Please send your entries to me by July 8th at midnight (Eastern Time). You can send your entries to: the DOT synapse DOT carnival…
cortex | June 24, 2006This comment was in response to my earlier post which argued that researchers should try to discover the genetic causes of mental illness instead of trying to decipher intelligence. The commenter makes some excellent points, although I still believe that untangling the (incredibly) complicated genetic underpinnings of mental illness has far more social value than connecting the dots between IQ and race.
It's far from clear that schizophrenia is a less complex phenomenon than intelligence. In fact, the opposite may be true. In the first instance, schizophrenia isn't an 'unambiguous…
clock | June 23, 2006
Since everyone is posting about spiders this week, I though I'd republish a sweet old post of mine, which ran on April 19, 2006 under the title "Happy Bicycle Day!" I hope you like this little post as much as I enjoyed writing it:
This week's theme for the Tar Heel Tavern is bicycle. I was wondering what to write about. Perhaps about crazy bicycle rides I had as a kid. Or a fun riff on "fish needing a bicycle". Then, I was saved! Because, today is the Bicycle Day! That's just great, because I can go on a scientific tangent with a local flavor.
If you do not know what Bicycle Day is,…
clock | June 23, 2006Is this what makes us scientists function on a daily basis? Are we just junkies for comprehension?
Neuroscientists have proposed a simple explanation for the pleasure of grasping a new concept: The brain is getting its fix.
Hat-tip: Shakespeare's Sister
j7uy5 | June 22, 2006I've written about this
href="http://trots.blogspot.com/2005/02/pipeline-update-insomniaimplications.html">before,
but now there is some new information.
href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=Abstract&list_uids=16368265&query_hl=6&itool=pubmed_docsum"
rel="tag">Gaboxadol (THIP;
4,5,6,7-tetrahydroisoxazolo- [5,4-c] pyridin-3-ol)
is an investigational drug being developed by
title="company website" rel="tag"
href="http://www.lundbeck.com">Lundbeck in
conjunction with
href="http://www.merck.com/" rel="tag">Merck…
cortex | June 22, 2006In my post on Blink, I argued that Gladwell's book was a wee bit incoherent, and that this incoherence stemmed from his reliance on spiffy anecdotes instead of nitty-gritty scientific details. Katherine made an excellent comment:
I thought the problem with Blink was that he never really made a point. He basically said our first impressions are always right, so we should trust them ... except when they aren't right. His style of anecdotal evidence is indeed what makes him so readable, but he has a common problem of either not making a point, or citing anecdotes for both sides of the argument.…
purepedantry | June 21, 2006I must admit that in general I like David Brooks. He seems to lack the stridency of many pundits, and I don't generally like people who shout. He also tends -- like Walter Bagehot -- not to think that people who disagree with him are evil, just that they disagree with him.
But on this piece I think he may have gone a little off. (Incidentally I would read this excellent review by Language Log, which is where I found out about it. They go into it in considerably more detail than I plan to.)
Here's Brooks:
Over the past two decades, there has been a steady accumulation of evidence that…
purepedantry | June 21, 2006For some reason I have been seeing lots of neuroeconomics articles lately. Maybe it is because people enjoy using that prefix. This article caught my eye because I have been reading off the reservation -- a history of economics by Mark Skousen -- who in spite of a rather lengthy "Keynes is a complete yo-yo" rant writes a darn good history.
What I have learned from this extensive reading is that people -- at least in aggregate -- seek out the best deal. I know...utterly shocking that. Unless you are an economist. If you are an economist, you tend to write 1,400 page books and then be…
j7uy5 | June 21, 2006The title of this post is taken from the title of a USC
href="http://www.usc.edu/uscnews/stories/7800.html">press
release, about a topic in neuroscience. A guy at
USC named
href="http://geon.usc.edu/%7Ebiederman/" rel="tag">Irving
Biederman is studying the role of opioid (
title="Wikipedia link"
href="http://en.wikipedia.org/wiki/Enkephalin" rel="tag">enkephalin)
activity in visual perception.
Actually, the title of this post is misleading. His research
is not about beauty. Rather, it is about recognition,
salience and learning.
In order to understand his theory, it…
clock | June 21, 2006My post about sleep has been translated by Davide 'Folletto' Casali into Italian, and posted on his blog. You can see the translated post here. If you can read Italian (and even you do not - just for fun, and to reward his hard work), go and look around his blog.
clock | June 19, 2006
Melatonin is secreted in human mother's milk with a daily rhythm - high at night, undetectable during the day (see the figure under the fold):
It has been known for a long time that mother's melatonin entrains the circadian rhythms in the SCN (suprachiasmatic nucleus) of the embryos - thus they are born with a correct phase (time of day). However, a study in rats suggests that melatonin in mother's milk is unlikely to be able to entrain the pups circadian rhythms after they are born.
So, the appearance of melatonin in the milk of breastfeeding humans may either be:
a) just a by-product…
purepedantry | June 18, 2006As promised I have a response to this article in the New York Times (I had to spend a couple days marshalling my evidence). I thought I would summarize some evidence about what we know from behavioral genetics so you could understand why I think this article was so wrong. I have tried to classify what we know below by the kind of study that we use to know it. Hopefully this will make things a little bit more clear.
(WARNING: This post is what economists would call a Schumpeterian tome.)
People studying behavioral genetics in humans use three types of studies:
Twin studies: Twin studies…
clock | June 16, 2006It is impossible to cover all organ systems in detail over the course of just two lectures. Thus, we will stick only to the basics. Still, I want to emphasize how much organ systems work together, in concert, to maintain the homeostasis (and rheostasis) of the body. I'd also like to emphasize how fuzzy are the boundaries between organ systems - many organs are, both anatomically and functionally, simultaneously parts of two or more organ systems. So, I will use an example you are familiar with from our study of animal behavior - stress response - to illustrate the unity of the well-…
cortex | June 16, 2006The Wall Street Journal has a fascinating article on Bruce Lahn today. Last September, Lahn announced in Science that he had isolated two brain genes in humans which had undergone recent evolution, but only in certain populations. His paper contained maps which showed that the genetic changes had taken hold and spread widely in Europe, Asia and the Americas, but weren't common in sub-Saharan Africa. Needless to say, the data sparked an uproar. Now, nine months later, Lahn is leaving the field. "It's getting too controversial," he told the Journal.
This is a tough issue. On the one hand,…
purepedantry | June 15, 2006I was totally incensed by this article in the New York Times, largely because the science quoted -- what little there was in between the anecdotes -- was truly attrocious, ignorant of alternative views, and completely missing the point.
When I get a free moment I will provide some clear examples of why genetics is a factor in determining behavior but only in an environmental context. Until then Cognitive Daily and The Frontal Cortex seem to be confronting the issue quite ably.
purepedantry | June 15, 2006I love science. New Scientist reports a study looking at brain activation during the female orgasm. The results are let us say interesting.
His team recruited 13 healthy heterosexual women and their partners. The women were asked to lie with their heads in a PET scanner while the team compared their brain activity in four states: simply resting, faking an orgasm, having their clitoris stimulated by their partner's fingers, and clitoral stimulation to the point of orgasm.
The results of the study are striking. As the women were stimulated, activity rose in one sensory part of the brain,…
purepedantry | June 14, 2006Baboons show handedness in communicative gestures, tending to be right-handed. This paper analyzed the handedness of baboons to see if they were more likely to use their right or their left hands for communication.
Here is a key figure.
We know that there is a connection between handedness and the lateralization of language in humans. Humans are primarily right-handed, and the vast majority of right-handed people have their language functions lateralized to their left hemisphere. Left-handed people -- though the distinction is not as clear cut -- also usually show language function in…
neurotopia | June 14, 2006Pure Pedantry found this paper on leptin's effects in the hippocampus, and then went on to wonder
I have never heard of a link between leptin and memory. They also make this link between ABeta mice and leptin. ABeta is a protein whose accumulation has been linked to Alzheimer's. Mice that create to much ABeta show cognitive deficits. They show that an ABeta overproducing mouse also showed improvement when treated with leptin -- and link that result to the observation that leptin decreases ABeta. I am not sure what to make of that, but there is probably a metabolic story related to ABeta…
purepedantry | June 13, 2006This paper shows that leptin injections into the hippocampus improves memory in a T-maze footshock avoidance and step down inhibitory avoidance tasks. It caught my eye because I just finished a course in behavioral neuroscience, but I have never for the life of me thought the two were related.
Leptin is a hormone that is released by fat cells that tells your brain that you're good on food and that you should stop eating. Leptin insufficiency causes obesity. Before you get excited though you should know that leptin is not a diet drug because if you have too much of it your brain stops…
clock | June 13, 2006When a news release states that a brain region is crucial for something, one is led to believe that this is the MAIN center controlling that function. If it is crucial for thermoregulation than it is the center for thermoregulation and without it the animal does not thermoregulate. Or am I misunderstanding English (it is a second language for me, after all)?
So, when the article starts with: "Researchers at Northwestern University have pinpointed a brain area in flies that is crucial to sleep, raising interesting speculation over the purpose of sleep and its possible link with learning and…