Stories tagged brain
A white-throated sparrow: Is its tweeting music to the ears other birds?Courtesy Dave Govoni (Va bene!)Is birdsong music? Does the tweeting and chirping of our feathered friends elicit the same emotional response in them as one of Chopin’s nocturnes does in us? Do they serve the same purpose? These are questions that have long been argued in scientific circles and elsewhere.
A new study published recently in Frontiers of Evolutionary Neuroscience shows some interesting results in how birds perceive birdsong.
Researcher Sarah Earp and neuroscientist Donna Maney, both of Emory University looked at brain imaging data gathered from studies of human neural responses to music and compared them with similar data from birdsong studies.
Some of the white-throated sparrows were given a boost of hormones (testosterone and estradiol) that made them all a-twitter and ready for love. When a male sparrow stepped up to the microphone and started serenading, the females showed a definite response.
“We found that the same neural reward system is activated in female birds in the breeding state that are listening to male birdsong, and in people listening to music that they like,” said Sarah Earp.
But what was music to the ears of the female sparrows was perceived by their male counterparts as discordant (and probably very annoying) noise from a rival suitor. An awkward third-wheel sort of deal, I suppose.
“Birdsong is a signal,” said Maney. “And the definition of a signal is that it elicits a response in the receiver. Previous studies hadn’t approached the question from that angle, and it’s an important one.”
The females in the sample group showed increased activity in the same region of their bird brains that humans display in their corresponding region when hearing a piece of music they enjoy. The response of the control group females - those not in a breeding state and without any hormonal boost - showed little response to song. Male sparrows treated with testosterone showed an amygdala response not unlike how the human brain responds to scary movie music.*
The brain’s mesolimbic reward pathway has counterparts in both humans and birds. In humans it lies beneath the cerebrum and is involved in emotions, memory, and olfaction. A neurotransmitter called dopamine is produced within the brain’s limbic system and spreads along the limbic pathways to help regulate the brain’s reward and pleasure centers. The chemical messenger also governs movement and emotions.
The study shows that not only does birdsong and music produce similar responses in corresponding brain regions linked to reward but also in areas thought to regulate emotions. And the response also seems to connected to social context in both birds and humans.
“Both birdsong and music elicit responses not only in brain regions associated directly with reward, but also in interconnected regions that are thought to regulate emotion,” Earp said. “That suggests that they both may activate evolutionarily ancient mechanisms that are necessary for reproduction and survival.”
LINKS
Emory University story
Frontiers of Evolutionary Neuroscience
More about dopamine
The intelligence of birds
*Rather than scary, I find composer Bernard Herrmann’s musical score used in Alfred Hitchcock’s PSYCHO very compelling – not sure what that response means. But it’s interesting to note that Herrmann’s music in the movie was also a big influence on record producer George Martin’s string arrangement for the Beatles’ melancholy ballad ELEANOR RIGBY.
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Smoking messes up your brain's cognitive skills: Sure it's funny now, but see if you can remember to laugh about it in your 50s, pal.Courtesy jaduarteI don’t know why this should surprise anyone, but a study coming from King’s College in London suggests that smoking not only adversely affects your physical health but also damages your mental health, reducing your brain’s capacity to learn, reason, and remember.
The study was published in the journal Age and Aging and involved lifestyle data gathered from 8,800 people over 50 years of age. The study was looking for links between the likelihood of stroke or heart attack, and the condition of the brain. Four years after the initial data was collected, participants were examined again, and given brain tests, such as naming as many animals as they could in a minute’s time, or learning new words. The same tests were administered again eight years later.
Not only did participants with high-risk physical conditions such as obesity or high blood pressure fair poorly in the cognitive tests, but those who smoked had a “consistent association” with lower scores as well.
"We have identified a number of risk factors which could be associated with accelerated cognitive decline, all of which, could be modifiable," said Dr. Alex Dregan, one of the researchers involved. "We need to make people aware of the need to do some lifestyle changes because of the risk of cognitive decline."
Is this your brain on technology?Courtesy Wikimedia CommonsThis story on NewScientist's Culture Lab blog suggests that, because we've invented technologies that can do some of our thinking for us, humans are losing the need for biological intelligence. Think about it (if you still can, har har): computers can think much faster and keep track of much more data than one person's brain can, but cognition-saving devices go back much further than that. Writing and number systems allowed us to store and calculate information through physical media instead of memorization, and devices like the abacus (and then the slide rule and the electronic calculator) allowed us to do arithmetic with our fingers. Be honest: when have you used those times-tables you had to memorize? With all this technology, why would we still need the ability to memorize and calculate inside our brains?
Interesting point, right? If everything we ever used our brains for could be done better by a computer, I'd agree. But another way to look at the situation is to say that because technology can do the grunt work for us, our brains are free for higher-level processes of creativity and analysis. If I want to make up a story, I don't have to keep repeating the beginning over and over in my head so I don't forget it--I can write it down and then spend my mental energy thinking up the rest of the story instead. Landing humans on the moon or a rover on Mars takes calculation and computer power, but it couldn't have happened without human imagination to conceive of, and human ingenuity to solve, the obstacles that those feats presented.
What do you think? Will "outsourcing" our thinking to technology make us dumber, or will it free our brains up for other, more advanced kinds of thought?
Addict or non-addict brain?: A new study finds addicts and their siblings share the same brain abnormalities. This is a nifty picture of my gray matter (I'm so proud!) but you'll have to guess what it shows.Courtesy Mark RyanIs the circuitry of an addict's brain different because of drug abuse or is drug abuse caused by innate differences in the brain? This is one of the questions raised during a new study out of the University of Cambridge. Researchers there compared the brains of 50 addicted individuals with the brains of a non-addicted brother or sister. What they found was that both the addict and their non-addict sibling display the same abnormalities in the brain areas that control behavior. Yet, despite possessing this similar inborn brain disorder, the non-addict siblings somehow managed to avoid getting hooked into a self-destructive lifestyle. If the scientists can figure out how the siblings did that, it could open up new ways of treating addiction. The study appears in the journal Science.
SOURCE
BBC story
Neuroscientist Sheila Nirenberg studies neural coding at New York's Weill Medical College. In this TedTalk, Professor Nirenberg explains her recent work in determining how the brain gathers outside information and encodes it into patterns of electrical activity. Her research has led her to develop an amazing prosthetic retinal device aimed at treating blindness.
Using the high-speed drawing technique of RSA Animate, renowned psychiatrist and writer Iain McGilchrist explains how the gray matter between our ears operates. According to its website the RSA is "an enlightenment organisation committed to finding innovative practical solutions to today’s social challenges."
The brain: A new study shows promising benefits from physical exerciseCourtesy Mark RyanWe all know how physical exercise benefits the body, strengthening muscles and improving stamina, but is it also good for the brain? A
new study out of University of South Carolina is showing some interesting results. The eight-week study compared the brains of mice that spent time exercising on a treadmill to another group of rodents that just laid around doing nothing. The active group showed a marked increase in newborn mitochondrial organelles in the brain tissue, a response similar to what happens in the cells of muscle tissue. Mitochondria are the tiny organelles found inside the nucleus of most eukaryotic cells that power many cellular processes. The brain tissue of the couch-potato group showed no change in cell make-up. The hope is, if the same mitochondrial biogensis takes place in the human brain during exercise, it could act as a safeguard against the development of Alzheimer's, Parkinson's or other human brain diseases.
SOURCE and LINKS
Story in NY Times
American Physiological Society
What sort of exercise can make you smarter?
It's Friday, and y'all know what that means. Yup, time for a new Science Friday video.
Science FridayCourtesy Science Friday
This week,
"Many mammals have whiskers but not all whisk. Cats don't. Rats do. To whisk, rats use special muscles in their face to brush their whiskers against an object. From the bending bristles, rats seem to be able to decode an object's shape and texture and Mitra Hartmann, engineer at Northwestern University, wants to understand how. This week, Hartmann and colleagues published a 3D whisker model, which she says will help quantify what information the brain receives from a whisk."
Does a shrinking brain make us dumber, or is evolution just downsizing it into a lean, mean machine?
Normal human brain: Does this brain make my head look big?Courtesy Mark RyanAccording to a new study reported in Discovery magazine, over the past 20,000 years, the human brain has been shrinking in size. Whether this is good or bad in terms of evolution or intelligence is another question. But whatever the case, as musician/surgeon Charles Limb shows in a recent TED Talk, the way the brain functions continues to amaze us.
Normal human brain: Well, okay maybe Abby Normal is a better description. It is my brain after all. I had a recent MRI and was really glad to see I had something other than rocks in my head.Courtesy Mark RyanA new study appearing in the Journal of Palliative Medicine reports how several terminally ill patients all showed identical surges in their brain activity just before they died. At first the doctors at George Washington University Medical Faculty Associates who did the study thought the surge was being caused by interference from life-support machines or other electronic gear in the room.
“But then we started removing things, turning off cell phones and machines, and we saw it was still happening,” said lead author Lakhmir Chawla.
Speculation of what causes the neurological hyperactivity at the moment of death is that neurons in the brain, suddenly deprived of blood pressure and oxygen, shut down in rapid succession resulting in a final burst of neural activity - an electrical death rattle if you will. But the idea doesn’t seem to be a very new one. Kevin Nelson, a researcher studying near-death experiences at the University of Kentucky claims it’s well known that the brain experiences a sudden discharge of electrical energy when blood flow to it is cut off.
So, I’m not sure I see what the big surprise is here. If this is so well-known then why wouldn’t the doctors at George Washington University Medical Associates already know this?
But there’s another part of this that’s interesting. The surge may also be responsible for the "white light" reported by some patients who have had near-death episodes. The lore surrounding this phenomenon is about patients seeing an intense bright light when they're dying. But, according to Chawla, the majority of people involved in such incidents report having no such “white light” occurrence, but merely a vivid memory that may have been burned into their brain by the “final” electrical discharge.
And what about the so-called "out of body experience" patients sometimes report after slipping from the grasp of the Grim Reaper? Well, that, too, could come from the brain's electrical shutdown. A study that appeared in the journal Nature in 2006 reported patients sensing "shadow figures" laying nearby, or hovering above while certain areas of their brains were being stimulated with electrical currents. The charges interfered with the sensory information being received by the brain, and the hallucinations were just the brain's way of making senses of everythingl. The New York Times ran a story about it you can read here.
Bottom line, it looks like all those reported supernatural near-death experiences are just all in your head.
SOURCES
Discovery News story
International Association for Near-Death Studies website
