Brain and Behavior
grrlscientist | August 1, 2007tags: researchblogging.org, white-crowned sparrow, Zonotrichia leucophrys, steroids, brain growth
White-crowned sparrow, Zonotrichia leucophrys [song and other information].
Image: Birds of Oklahoma.
The first thing that most people think of when they hear the word "steroids" is baseball players who rely on these chemicals to increase their muscle mass and thereby improve their athletic performance. But recently, a small songbird that I studied for my dissertation work, Gambel's white-crowned sparrow, Zonotrichia leucophrys gambelii, has shown scientists that steroids trigger the growth…
oracknows | July 31, 2007A couple of weeks ago, inspired by a somewhat drunken encounter two weeks prior, against my better judgment, I waded into the evidence supporting the contention that secondhand smoke is harmful to health, increasing the risk of heart disease and lung cancer in workers chronically exposed to it. In response to a list of quotes going around the Internet claiming that relative risks less than 2 are so unreliable that they may be ignored (conveniently enough, most relative risks reported for exposure to SHS are in the 1.2 to 1.3 range), I pointed out what a load of dishonest quotemining the list…
clock | July 31, 2007Going into more and more detail, here is a February 11, 2005 post about the current knowledge about the circadian organization in my favourite animal - the Japanese quail.
Japanese quail (Coturnix coturnix japonica), also known as the Asian Migratory Quail, are gallinaceous birds from the family Phasianidae, until 1960s thought to be a subspecies of European migratory quail (Coturnix coturnix coturnix), but now considered to be a separate species, designated as Coturnix japonica. The breeding range of the wild population encompasses Siberia, Mongolia, northeastern China and Japan, while the…
dmunger | July 31, 2007Here's an interesting question:
If we shipwrecked a boatload of babies on the Galapagos Islands--assuming they had all the food, water, and shelter they needed to survive--would they produce language in any form when they grew up?
It comes from Christine Kenneally, who posed the question to a group of experts in the field. It's a fascinating dilemma--are we all born with language "inside" of us; will it emerge without the social guidance of parents and other language speakers, or does each successive generation have to learn language anew?
Edmond Blair Bolles has provided a nice summary of…
hrynyshyn | July 30, 2007Are we ScienceBloggers just wasting our time when it comes to politics? While I'm sure that none of us are operating under the delusion that anything we write has a significant influence on the outcome of pivotal events like presidential elections, could it be that the scientific, rational approach to running this country is completely irrelevant? Do Americans, by and large, actually distrust intelligence and reason to the point where they prefer their candidates be ignorant and simple-minded? In other words, was George W. Bush more than an aberration?
Ten days ago on NPR's All Things…
clock | July 30, 2007 This post was originally written on February 11, 2005. Moving from relatively simple mammalian model to more complex systems.
I have previously described the basic properties of the circadian organization in mammals. Non-mammalian vertebrates (fish, amphibians, reptiles and birds) have more complex circadian systems than mammals. While the suprachiasmatic area remains a site of circadian pacemakers, it is, unlike in mammals, not the only such site.
The pineal organ, which in mammals is a purely secretory organ, is directly photosensitive in other vertebrates (with the exception of snakes)…
dmunger | July 30, 2007You might think the best way to make a robot seem more "human" is to reproduce human features as precisely as possible, like in this YouTube video:
But most people are creeped out by robots this "real." We're actually more comfortable interacting with less realistic robots that exhibit some human traits, like this adorable robot named Leo:
So why is this less realistic robot so much more endearing? A fascinating article in this week's New York Times Magazine may offer some answers:
If a robot had features that made it seem, say, 50 percent human, 50 percent machine ... we would be willing…
retrospectacle | July 27, 2007 Attention deficit hyperactivity disorder (ADHD), currently the most common childhood-onset behavioral disorder, is nothing if not controversial. Nearly every aspect of ADHD from diagnosis to prevalence to medication, and even its mere existence, is disputed by at least one 'concerned' group. And honestly, who could blame parents for being hesitant to medicate their young children, especially since medications come with risks? However, ADHD is a very real (and prevalent) disorder which has discrete neurochemical and, as more and more research is suggesting, genetic causes. It has been linked…
clock | July 25, 2007In this post from April 06, 2006, I present some unpublished data that you may find interesting.
Understanding the role of serotonin in depression has led to development of anti-depressant drugs, like Prozac. Much of the research in this area has been performed in Crustaceans: lobsters and crayfish. The opposite behavioral state of depression, something considered a normal state, could possibly best be described as self-confidence.
Self-confidence is expressed differently in different species, but seems to always be tied to high status in a social hierarchy. In crayfish, self-confidence is…
pharyngula | July 24, 2007There's always the quick and easy icepick lobotomy for rapid relief.
All joking aside, follow the link: it tells of the infamous Dr Walter Freeman, who lobotomized thousands of people in this horrific fad of irreversibly ripping up people's brains to change their behavior. The story of poor Howard Dully, whose stepmother had him lobotomize at the age of 12, is particularly tragic.
clock | July 24, 2007This post (click on the icon) was originally written on May 07, 2005, introducing the topic of neuroendocrine control of seasonal changes in physiology and behavior.
So far, I have directed all my attention to daily - circadian - rhythms, and pretty much ignored other rhythms that correspond to other cycles in nature. Another obvious cycle in nature is the procession of seasons during a year.
Just as an environment during the day is different from the same environment during the night and thus requires different adaptations for survival, so the winter environment and the summer environment…
zooillogix | July 23, 2007Turns out that honey bees might not have the ideal socialist society after all. Researchers at Otago University in New Zealand have discovered that worker bees behave like drones because of a powerful, brainwashing pheromone released by the queen. The queen bee prevents aggressive behavior in the workers by releasing homovanillyl alcohol or HVA. As described by the New Zealand Herald, the HVA, released from the queen's mandibles, "blocks aversive learning, the acquisition of negative memories which would normally trigger an aggressive 'sting reflex' in the bees." Bees who don't learn to sting…
pharyngula | July 23, 2007The first review of my talk yesterday is in! Too bad it is from somebody who wasn't there and who is a world-class fool. Yes, it's Michael Egnor again, and he's got a lengthy post up with the pretext of giving me advice on future talks, but is really an attempt to preempt my arguments and chide me for my crazy materialist position. He doesn't even come close to any of my arguments, and he makes false assumptions all over the place about what I and the audience think. I'm used to straw men from creationists, but this is ridiculous.
Here's what I actually said at the talk.
The first half was…
clock | July 22, 2007This is an appropriate time of year for this post (February 05, 2006)...
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So, why do I say that it is not surprising the exposure to bright light alleviates both seasonal depression and other kinds of depression, and that different mechanisms may be involved?
In mammals, apart from visual photoreception (that is, image formation), there is also non-visual photoreception. The receptors of the former are the rods and cones that you all learned about in middle school. The receptors for the latter are a couple of thousand Retinal Ganglion…
clock | July 21, 2007A January 20, 2006 post placing a cool physiological/behavioral study into an evolutionary context.
There are two main hypotheses - not mutually exclusive - for the adaptive value of having a circadian clock. One is the Internal Synchronization hypothesis, stating that the circadian clock serves to synchronize biochemical and physiological processes within the body. The second is the External Synchronization hypothesis, stating that the circadian clock serves to syncronize the physiology and behavior to the natural environment.
The prediction from the Internal Hypothesis is that circadian…
neurophilosophy | July 21, 2007We live in a time in which we are overwhelmed by information obtained from multiple sources, such as the internet, television, and radio. We are usually unable to give our undivided attention to any one source of information, but instead give 'continuous partial attention' to all of them by constantly flitting between them. The limitations of cognitive processes, particularly attention and working memory, place a ceiling on the capacity of the brain to process and store information. It is these processes that some researchers are aiming to enhance with augmented cognition, an emerging field…
razib | July 19, 2007Natural polymorphism affecting learning and memory in Drosophila:
Knowing which genes contribute to natural variation in learning and memory would help us understand how differences in these cognitive traits evolve among populations and species. We show that a natural polymorphism at the foraging (for) locus, which encodes a cGMP-dependent protein kinase (PKG), affects associative olfactory learning in Drosophila melanogaster. In an assay that tests the ability to associate an odor with mechanical shock, flies homozygous for one natural allelic variant of this gene (forR) showed better short-…
oracknows | July 19, 2007Little did I know when I posted my first article on the evidence supporting health hazards due to secondhand smoke that it would end up dominating the comments of this blog for three full days and lead me to a site that's so full of pseudoscience, logical fallacies, and just plain B.S. that it is worthy of the title of the Whale.to of the tobacco nuts. Even less did I expect that the crankfest would spread to fellow SBer Mark's denialism blog as well. The sheer vitriol that some of these "smoking rights" advocates direct at any suggestion that SHS might be harmful, quite frankly, took me…
bcohen | July 19, 2007
forearm musculature
The Bishopsgate Ward train depot, as taken from W.G. Sebald's Austerlitz (p. 133)
circuitry
This is another from our mid-summer's series of reposts from the vault -- ours or others', of which this one is both -- but now from the very top of that vault, since it's but a week old.
Fortunately, I'm both absent-minded and lazy. Many moons ago I sent Lawrence Weschler a hurried note about a series of visual convergences that'd struck me. Then I forgot about it. Then, much later, I was going to post the same commentary on those convergences at this blog, having thought…
j7uy5 | July 18, 2007
There is new information
indicating that an
rel="tag">oxytocin
nasal spray could be used to
treat shyness. Oxytocin is a peptide hormone best known for
its role in childbirth and breastfeeding. These are known as
peripheral actions, meaning they take place outside of the central
nervous system (CNS).
However,
it also is
known as a neurotransmitter, having effects within the CNS.
It
has been touted as a chemical that can increase trust and reduce fear.
It also has been claimed to have a role in the difference in
how
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