LiveScience

Left Brain vs. Right: It’s a Myth, Research Finds

It’s the foundation of myriad personality assessment tests, self-motivation books and team-building exercises – and it’s all bunk.

Popular culture would have you believe that logical, methodical and analytical people are left-brain dominant, while the creative and artistic types are right-brain dominant. Trouble is, science never really supported this notion.

Now, scientists at the University of Utah have debunked the myth with an analysis of more than 1,000 brains. They found no evidence that people preferentially use their left or right brain. All of the study participants — and no doubt the scientists — were using their entire brain equally, throughout the course of the experiment.

A paper describing this study appeared in August in the journal PLOS ONE.

The preference to use one brain region more than others for certain functions, which scientists call lateralization, is indeed real, said lead author Dr. Jeff Anderson, director of the fMRI Neurosurgical Mapping Service at the University of Utah. For example, speech emanates from the left side of the brain for most right-handed people. This does not imply, though, that great writers or speakers use their left side of the brain more than the right, or that one side is richer in neurons.

There is a misconception that everything to do with being analytical is confined to one side of the brain, and everything to do with being creative is confined to the opposite side, Anderson said. In fact, it is the connections among all brain regions that enable humans to engage in both creativity and analytical thinking.

“It is not the case that the left hemisphere is associated with logic or reasoning more than the right,” Anderson told LiveScience. “Also, creativity is no more processed in the right hemisphere than the left.”

Anderson’s team examined brain scans of participants ages 7 to 29 while they were resting. They looked at activity in 7,000 brain regions, and examined neural connections within and between these regions. Although they saw pockets of heavy neural traffic in certain key regions, on average, both sides of the brain were essentially equal in their neural networks and connectivity.

“We just don’t see patterns where the whole left-brain network is more connected, or the whole right-brain network is more connected in some people,” said Jared Nielsen, a graduate student and first author on the new study.

The myth of people being either “left-brained” or “right-brained” might have arisen from the Nobel Prize-winning research of Roger Sperry, which was done in the 1960s. Sperry studied patients with epilepsy, who were treated with a surgical procedure that cut the brain along a structure called the corpus callosum. Because the corpus callosum connects the two hemispheres of the brain, the left and right sides of these patients’ brains could no longer communicate.

Sperry and other researchers, through a series of clever studies, determined which parts, or sides, of the brain were involved in language, math, drawing and other functions in these patients. But then popular-level psychology enthusiasts ran with this idea, creating the notion that personalities and other human attributes are determined by having one side of the brain dominate the other.

The neuroscience community never bought into this notion, Anderson said, and now we have evidence from more than 1,000 brain scans showing absolutely no signs of left or right dominance.

Anderson said he wasn’t out to do some myth busting. His team’s goal is to better understand brain lateralization to treat conditions such as Down syndrome, autism or schizophrenia, where the left and right hemispheres have atypical roles.

So, should you trash your app that tries to determine if you are a left-brain or right-brain thinker? Both sides of your brain, as well as neuroscientists, say yes.

And in other news, fire burns.

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Your smartphone just got smarter.

A device invented by biomedical engineers at Columbia University turns a smartphone into a lab that can test human blood for the virus that causes AIDS or the bacteria that cause syphilis.

The researchers got the idea for the device when examining the costs and the logistical difficulties of getting equipment for HIV testing to rural areas or developing countries.

Learn more about the device here.

Dolphins ‘Talk’ Like Humans, New Study Suggests

by Jeanna Bryner, LiveScience Managing Editor


Dolphins “talk” to each other, using the same process to make their high-pitched sounds as humans, according to a new analysis of results from a 1970s experiment.

The findings mean dolphins don’t actually whistle as has been long thought, but instead rely on vibrations of tissues in their nasal cavities that are analogous to our vocal cords.

Scientists are only now figuring this out, “because it certainly sounds like a whistle,” said study researcher Peter Madsen of the Institute of Bioscience at Aarhus University in Denmark, adding that the term was coined in a paper published in 1949 in the journal Science. “And it has stuck since.”

The finding clears up a question that has long puzzled scientists: How can dolphins make their signature identifying whistles at the water’s surface and during deep dives where compression causes sound waves to travel faster and would thus change the frequency of those calls.

To answer that question, Madsen and his colleagues analyzed recently digitized recordings of a 12-year-old male bottlenose dolphin (Tursiops truncatus) from 1977. At the time, the researchers had the dolphin breathe a mixture of helium and oxygen called heliox. (Used by humans, heliox makes one sound like Donald Duck.)

The heliox was meant to mimic conditions during a deep dive since it causes a shift up in frequency. When breathing air or heliox, the male dolphin, however, continued to make the same whistles, with the same frequency.

Rather than vocal cords, the dolphins likely use tissue vibrations in their nasal cavities to produce their “whistles,” which aren’t true whistles after all. The researchers suggest structures in the nasal cavity, called phonic lips, are responsible for the sound.

The dolphins aren’t actually talking, though.

“It does not mean that they talk like humans, only that they communicate with sound made in the same way,” Madsen told LiveScience.

“Cetean ancestors lived on land some 40 million years ago and made sounds with vocal folds in their larynx,” Madsen said, referring to the group of mammals to which dolphins belong. “They lost that during the adaptations to a fully aquatic lifestyle, but evolved sound production in the nose that functions like that of vocal folds.”

This vocal ability also likely gives dolphins a broader range of sounds.

“Because the frequency is changed by changing the airflow and the tension of the connective tissue lips in the nose, the dolphin can change frequency much faster than if it had to do it by changing air sac volumes,” Madsen said. “That means that there is a much bigger potential for making a broader range of sounds and hence increase information transfer.”

The research is detailed this week in the journal Biology Letters.

Image Credit: © Copyright 2011 Chris Johnson – earthOCEAN. All Rights Reserved.

7 Billion People: Should World Adopt ‘One Child’ Policy?__The problem in nations with low fertility rates — those that have rates so low that they won’t replace the current population — is that there are far more old people than young people, which means there is a greater burden on those young people to financially and socially support their elders. Japan currently struggles with this, and China is about a decade away from facing a similar situation, Bongaarts said. If the worldwide fertility rate dropped to just one birth per woman, it could unbalance society and the global economy.

And, once a low fertility pattern starts, it’s difficult to reverse. “Demography is not like a tap, unfortunately. It’s not like turning water on and off,” explained George Leeson, a demographer at the Oxford Institute of Population Aging. “Once you’ve turned off the tap it can be difficult to get it running again.”

As if the outdoors weren’t harsh enough with Boston buried under ungodly amounts of snow and the rest of the Northeast unable to shake the bitter cold, more winter weather is on the way. So what’s behind this extreme chill?
The freezing weather is part of a weather pattern that began last year, when the polar vortex, a system of cold air swirling around the Arctic, began pushing cold air into the United States. This pattern continued on and off throughout the summer, explaining the cooler temperatures in the eastern United States, said Bob Oravec, a forecaster at the National Weather Service.

Good read by LiveScience. Unclear if anthropogenic climate change influenced this phenomena.

CIA Science Experiment: Mind Control

Talk about a bad trip. In the 1950s, the CIA launched a top-secret program called MKULTRA to look for drugs and other techniques to use in mind control. Over the next two decades, the agency used hallucinogens, sleep deprivation and electrical shock techniques in an effort to perfect brainwashing.

Keep reading

We have fingernails because we’re primates.

“Most mammals have claws,” Hawks told LiveScience. “[They] use them to grab onto things, to climb things, to scratch things, and to dig holes.”

Scientists suspect primates sort of lost their claws and fashioned broad fingertips topped with nails to aid in locomotion. While claws would have provided excellent grip as our mammalian ancestors clambered up large tree trunks, they would have been a nuisance for larger-bodied primates trying to grasp smaller branches while scrambling across tree canopies for fruits. Rather, primates developed broader fingertips made for grasping.

About 2.5 million years ago, fossil evidence suggests early humans first picked up stone tools, which is about the same time our ancestors also developed even broader fingertips than earlier primates. To this day, humans sport broader fingertips than other primates.

Whether fingernails are an adaptation that helps to support broad fingertips or a side effect from the loss of claws is unclear, Hawks said.

Another reason for fingernails: They serve as a visual advertisement of a person’s health, he said. For instance, malnutrition can change the coloring of nails, while small pits in fingernails can signal the skin condition psoriasis.

To learn more about the smartest invertebrates on Earth, LiveScience caught up with Katherine Harmon Courage to talk about her new book “Octopus! The Most Mysterious Creature In the Sea.”

A very cool article on octopuses/octopis/octopodes.  Read it to know how best to serve your future genius multilimbed overlords.

3.5 million years ago, carnivorous “Terror Birds” with hooked beaks standing 10 feet tall roamed portions of South America in search of prey which they hatcheted with their huge beaks.  Researches have found a 90% complete skeleton of a new species (Llallawavis scaglia) which is providing surprising new details about their hearing an anatomy.  Read more

The scientific paper can be found here

Also be sure to visit the Fossil Porn Tumblr Blog for more amazing fossil photos, links and new stories.

6 Weird Facts About Gravity

1. It’s all in your head

Gravity may be pretty consistent on Earth, but our perception of it isn’t. According to research published in April 2011 in the journal PLoS ONE, people are better at judging how objects fall when they’re sitting upright versus lying on their sides.

The finding means that our perception of gravity may be less based on visual cues of gravity’s real direction and more rooted in the orientation of the body. 

2. Coming down to Earth is tough

Astronaut’s experience has shown that a switch to weightlessness and back can be tough on the body. In the absence of gravity, muscles atrophy and bones likewise lose bone mass. According to NASA, astronauts can lose 1 percent of their bone mass per month in space.

When astronauts come back to Earth, their bodies and minds need time to recover. Blood pressure, which has equalized throughout the body in space, has to return to an Earthly pattern in which the heart must work hard to keep the brain nourished with blood. Occasionally, astronauts struggle with that adjustment. In 2006, astronaut Heidemarie Stefanyshyn-Piper collapsed at a welcome-home ceremony the day after returning from a Space Shuttle mission to the International Space Station.

The mental readjustment can be just as tricky. In 1973, Skylab 2 astronaut Jack Lousma told Time magazine that he’d accidentally smashed a bottle of aftershave in his first days back from a month-long sojourn in space. He’d let go of the bottle in mid-air, forgetting that it would crash to the ground rather than just float there.

3. For weight loss, try Pluto

Pluto may no longer be a planet, but it’s still a good bet for lightening up. A 150-pound (68 kilogram) person would weigh no more than 10 pounds (4.5 kg) on the dwarf planet. The planet with the most crushing gravity, on the other hand, is Jupiter, where the same person would weigh more than 354 pounds (160.5 kg).

The planet humans are most likely to visit, Mars, would also leave explorers feeling light-footed. Mars’ gravitational pull is only 38 percent that of Earth’s, meaning a 150-pound person would feel like they weigh about 57 pounds (26 kg). 

4. Gravity is lumpy

Even on Earth, gravity isn’t entirely even. Because the globe isn’t a perfect sphere, its mass is distributed unevenly. And uneven mass means slightly uneven gravity.

5. Without gravity, some bugs get tougher

Bad news for space cadets: Some bacteria become nastier in space. A 2007 study published in the journal Proceedings of the National Academy of Sciences found that salmonella, the bacteria that commonly causes food poisoning, becomes three times more virulent in microgravity. Something about the lack of gravity changed the activity of at least 167 salmonella genes and 73 of its proteins. Mice fed the gravity-free salmonella got sick faster after consuming less of the bacteria.

In other words, Michael Crichton’s “The Andromeda Strain” had it wrong: The danger of infection in space may not come from space bugs. It’s more likely our own bugs grown stronger would strike us.

6. Black holes at the center of galaxies

Named because nothing, not even light, can escape their gravitational clutches, black holes are some of the most destructive objects in the universe. At the center of our galaxy is a massive black hole with the mass of 3 million suns. Scarier thought? It might be “just resting,” according Kyoto University scientist Tatsuya Inui.

The black hole isn’t really a danger to us Earthlings – it’s both far away and it’s remarkably calm. But sometimes it does put on a show: Inui and colleagues reported in 2008 that the black hole sent out a flare of energy 300 years ago. Another study, released in 2007, found that several thousand years ago, a galactic hiccup sent a small amount of matter the size of Mercury falling into the black hole, leading to another outburst.

The black hole, named Sagittarius A*, is dim compared with other black holes.

“This faintness implies that stars and gas rarely get close enough to the black hole to be in any danger,” Frederick Baganoff, a researcher at the Massachusetts Institute of Technology who was involved with the 2007 study, told LiveScience’s sister site SPACE.com. “The huge appetite is there, but it’s not being satisfied.”

“Because of their cultural sophistication these are enormously vulnerable individuals,” said Lori Marino, who studies brain and behavioral evolution in mammals at Emory University in Atlanta. “We have all the evidence to show that there is an egregious mismatch between how cetaceans are and how they are perceived and still treated by our species.”

Giving rights to cetaceans, the name for the group of marine mammals that includes dolphins and whales, would allow them better treatment under the law, including making sure they have healthy habitats and enough food to hunt and survive, as well as getting them out of captivity.

Monkey brains grow bigger with every cagemate they acquire, according to a new study showing that certain parts of the brain associated with processing social information expand in response to more complex social information.

This article says to me: Expand your brain! Go out, participate in all sorts of clubs and activities and make more friends!