Clipmarks | wildcat's 'brain' clips

Animal Intelligence and the Evolution of the Human Mind

Wed, 03 Sep 2008 11:50:26 GMT

clipped by: wildcat
clipper's remarks: Subtle refinements in brain architecture, rather than large-scale alterations, make us smarter than other animals

Clip Source: www.sciam.com

The human brain lacks conspicuous characteristics—such as relative or absolute size—that might account for humans’ superior intellect.

Researchers have found some clues to humanity’s aptitude on a smaller scale, such as more neurons in our brain’s outermost layer.

Human intelligence may be best likened to an upgrade of the cognitive capacities of nonhuman primates rather than an exceptionally advanced form of cognition.

As far as we know, no dog can compose music, no dolphin can speak in rhymes, and no parrot can solve equations with two unknowns. Only humans can perform such intellectual feats, presumably because we are smarter than all other animal species—at least by our own definition of intelligence.

Of course, intelligence must emerge from the workings of the three-pound mass of wetware packed inside our skulls

Thus, researchers have tried to identify unique features of the human brain that could account for our superior intellectual abilities

Tags: brain, mind, evolution, intelligence

Addicted to Grief?

Fri, 18 Jul 2008 11:07:53 GMT

clipped by: wildcat
clipper's remarks: When time doesn't heal, the brain's reward system may be playing a role

Clip Source: www.sciam.com

Losing a loved one is always painful, but for most people time eventually heals the wounds. For about 10 to 20 percent of the bereaved, however, accepting and getting over a loss remains extremely difficult, even years later. Now researchers have come a step closer to elucidating the neurobiological underpinnings of this condition called complicated grief (CG). A new functional magnetic resonance imaging (fMRI) study, published online in May in the journal NeuroImage, shows that in CG patients reminders of the deceased activate a brain area associated with reward processing, pleasure and addiction.

While in the scanner, the women saw pictures and words that reminded them of their loved one. Brain networks associated with social pain became activated in all women, but in the CG patients reminders of the deceased also excited the nucleus accumbens, a forebrain area most commonly associated with reward.

Tags: grief, mind, healing, time, brain

'Mind's eye' influences visual perception

Wed, 02 Jul 2008 10:14:20 GMT

clipped by: wildcat
clipper's remarks: ..even a single instance of imagery can tilt how you see the world one way or another..

Clip Source: www.physorg.com

Letting your imagination run away with you may actually influence how you see the world. New research from Vanderbilt University has found that mental imagery—what we see with the "mind's eye"—directly impacts our visual perception.

"We found that imagery leads to a short-term memory trace that can bias future perception," says Joel Pearson, research associate in the Vanderbilt Department of Psychology. and lead author of the study. "This is the first research to definitively show that imagining something changes vision both while you are imagining it and later on."

"You might think you need to imagine something 10 times or 100 times before it has an impact,"

Our results show that even a single instance of imagery can tilt how you see the world one way or another, dramatically, if the conditions are right."

"These findings are important because they suggest a potential mechanism by which top-down expectations or recollections of previous experiences might shape perception itself,"

Tags: 'mind's eye', visual perception, brain, imagination

Your brain lies to you

Mon, 30 Jun 2008 02:28:19 GMT

clipped by: wildcat
clipper's remarks: This phenomenon, known as source amnesia, can also lead people to forget whether a statement is true. Even when a lie is presented with a disclaimer, people often later remember it as true.

Clip Source: www.iht.com

False beliefs are everywhere. Eighteen percent of Americans think the sun revolves around the earth, one poll has found. Thus it seems slightly less egregious that, according to another poll, 10 percent of us think that Senator Barack Obama, a Christian, is instead a Muslim. The Obama campaign has created a Web site to dispel misinformation. But this effort may be more difficult than it seems, thanks to the quirky way in which our brains store memories - and mislead us along the way.

The brain does not simply gather and stockpile information as a computer's hard drive does. Facts are stored first in the hippocampus, a structure deep in the brain about the size and shape of a fat man's curled pinkie finger. But the information does not rest there. Every time we recall it, our brain writes it down again, and during this re-storage, it is also reprocessed. In time, the fact is gradually transferred to the cerebral cortex and is separated from the context in which it was originally learned

Tags: brain, misleading, false beliefs

Want to Enhance Your Brain Power?

Fri, 27 Jun 2008 15:37:38 GMT

clipped by: wildcat

Clip Source: www.technologyreview.com

Research hints that electrically stimulating the brain can speed learning.

A little brain boost is something we could all use now and then. A new option may be on the horizon. Researchers at the National Institute for Neurological Disorders and Stroke, in Bethesda, MD, are studying how applying gentle electrical current to the scalp can improve learning.

Previous small-scale studies have suggested that a stream of current can improve motor function, verbal fluency, and even language learning. To explore how effective such stimulation can be as a learning tool, Eric Wassermann, a neuroscientist at the National Institute for Neurological Disorders and Stroke, is using an approach known as transcranial direct current stimulation (TDCS), in which an electrical current is passed directly to the brain through the scalp and skull

researchers found that direct current stimulation could improve memory in participants asked to learn and then recall a list of 12 words

Tags: brain, memory, enhancement, boost, science

Will a Computer “Symbiote” be Implanted in Future Human Brains?

Thu, 26 Jun 2008 11:30:38 GMT

clipped by: wildcat

Clip Source: www.dailygalaxy.com

Will future humans have computers implanted in their brains? Researchers are developing a neural implant that can think independently—just like the human brain does. Creepy? Yeah. Cool? Definitely. Scientists at the University of Florida aren’t just creating a neural implant that can translate human brain signals, but one that can act independently to increase its efficiency and synergy with the brain as it learns new things.

"In the grand scheme of brain-machine interfaces, this is a complete paradigm change," said Justin C. Sanchez, Ph.D., a UF assistant professor of pediatric neurology and the study's lead author. "This idea opens up all kinds of possibilities for how we interact with devices. It's not just about giving instructions but about those devices assisting us in a common goal. You know the goal, the computer knows the goal and you work together to solve the task."

These “brain computers” are programmed with complex algorithms that can interpret thoughts

Tags: brain, implants, future, neurology, interface

When It Comes to Brains, Size Matters

Sat, 21 Jun 2008 01:27:35 GMT

clipped by: wildcat

Clip Source: physorg.com

Findings of a three-year study by researchers at the University of California, Riverside and the University of Florida, Gainesville run counter to the popular belief that women have better language skills than men.

In a study of 200 university students, the researchers found that women and men performed similarly on tests of language and reading skills. Differences in brain organization between men and women may be driven by sex differences in brain size, they said.

“People have said women have relatively larger language areas of the brain,” said Christine Chiarello, UCR professor of psychology. “In none of our language tasks were women better than men. When you account for differences in brain size between men and women there are few differences in the relative size of areas. While there are differences between men and women, those differences are minimal compared to the wide range of individual differences in both sexes.”

Tags: brain, size, language

115-year-old Woman's Brain in Tip-Top Shape

Mon, 16 Jun 2008 09:22:06 GMT

clipped by: wildcat

Clip Source: www.livescience.com

A Dutch woman who reached 115 years of age and remained mentally sharp throughout life also had a healthy brain when she died, a new study finds.

The woman's brain showed almost no evidence of Alzheimer's disease. The finding suggests Alzheimer's disease and other forms of dementia are not inevitable, as had been suspected.

"Our observations suggest that, in contrast to general belief, the limits of human cognitive function may extend far beyond the range that is currently enjoyed by most individuals," said lead researcher Gert Holstege, a neuroscientist at the University Medical Center Groningen, in The Netherlands.

At age 82, the Dutch woman made arrangements to donate her body to science after death. She contacted Holstege when she reached age 111, worried that her body was too old to be useful for research or teaching purposes. The neuroscientists reassured her that, contrary to her belief, they were particularly interested due to her age.

Tags: aging, brain, tip-top

Brain scans of porn viewers

Tue, 17 Jun 2008 11:17:07 GMT

clipped by: wildcat

Clip Source: www.boingboing.net

Researchers from the University of Picardie Jules Verne were curious about what happens in the brain to cause an erection when men are exposed to certain images. Specifically, they wondered whether "mirror neurons," are involved in the erection response. Mirror neurons fire both when you do something and when you observe that same thing being done by another. So Harold Mouras and his colleagues showed porn videos to eight men while scanning their brains. (The videos were mixed in with fishing documentaries and other footage that isn't erotic, er, to most people.) Meanwhile, they used a "penile plethysmograph" to determine when the men got erections and how hard they were. From New Scientist:

Interestingly, the volume of the erections correlated with the strength of activation in a part of the brain called the pars opercularis, which is known to display mirror neuron activity. Even more intriguing, the brain activation, say the researchers, precedes the penile response.

Tags: brain, porn, mirror neurons

6 iconoclastic discoveries about the brain

Wed, 11 Jun 2008 10:02:06 GMT

clipped by: wildcat
clipper's remarks: let go of the dogma

Clip Source: scienceblogs.com

Neuroscience, like all other branches of science, is fraught with dogmatic ideas about its subject matter. A number of principles have emerged, principles that have been regarded as fundamental to our understanding of brain function.

But the human brain is an organ of bewildering complexity - it is often referred to as the most complex object in the known universe - which doesn't give up its secrets easily. After 100 years of scientific investigation, we still know very little about it.

Dogma 1:

The adult human brain is not plastic.

Dogma 2: The adult human brain cannot regenerate

Dogma 3:

Neurons are the functional elements of the nervous system

Dogma 4:

Neurotransmitters are released from the nerve terminal

Dogma 5:

Neurons are binary switches.

Dogma 6:

Neurons communicate with each other by propagating action potentials

Tags: brain, discoveries, neuroscience, clipversity

Lab wants to capture minds... Literally!

Fri, 06 Jun 2008 09:15:51 GMT

clipped by: wildcat

Clip Source: memebox.com

The mega-billion dollar Howard Hughes Medical Institute (HHMI) recently developed a new state-of-the-art facility – Janelia Farm Research Campus – to learn how brain cells store and process information.

Today, biologists can only observe a cell’s activity by indirectly analyzing chemicals it produces in response to stimulus. But what if you could take a picture of a brain cell at the very moment it recorded a thought? HHMI researchers believe this worthy goal can be achieved and they are rounding up some of the top researchers in the world to make it happen.

Janelia Farm will provide its world-class science team with near unlimited funds in a mostly unsupervised environment. “The Institute’s core belief is that scientists who demonstrate creativity and imagination make lasting contributions to benefit humanity when they are given flexible, long-term support and the freedom to explore,” said former HHMI President Thomas Cech.

Tags: mind, biology, brain

The evolution of drug abuse

Sat, 22 Mar 2008 09:47:05 GMT

clipped by: wildcat
clipper's remarks: "All this shows “our ancestors were regularly exposed to plant neurotoxins,” they added, so the view of our brains as unsuspecting victims of the new chemical threat is untenable. "
" One possibility, the scientists suggested, is that animals co-opted some plant toxins and used them for their own defenses against parasites. If this is true, then evolution, the process by which species adapt and change to meet environmental demands, might have designed our brains to encourage some drug use. This could involve shaping our brains to associate drug intake with feelings of reward."

Clip Source: www.world-science.net

Why do people abuse drugs? It’s not only a question worried parents ask their wayward, substance-dab

bling teenagers. It’s also a deeper question asked by biologists.

In general, nature has designed all creatures as exquisite machines for their own protection and propagation. Yet we’re easily and often drawn into self-destruction by nothing more than lifeless chemical lures. This weakness seems such a jarring exception, such a dismal Achilles’ heel, that it seems to demand explanation.

Scientists typically offer the following one. Drugs are chemicals that inappropriately trigger activity in brain circuits designed for very different purposes: to provide a sense of reward for having satisfied ordinary needs, healthfully.

The brain has few defenses against this chemical deception, the standard account goes, because drugs were unknown in the natural environment that shaped human evolution.

Tags: drugs, evolution, brain, adaptation

Plastic Brain Outsmarts Experts

Fri, 06 Jun 2008 08:08:08 GMT

clipped by: wildcat

Clip Source: physorg.com

Can human beings rev up their intelligence quotients, or are they stuck with IQs set by their genes at birth? Until recently, nature seemed to be the clear winner over nurture.

But new research, led by Swiss postdoctoral fellows Susanne M. Jaeggi and Martin Buschkuehl, working at the University of Michigan in Ann Arbor, suggests that at least one aspect of a person's IQ can be improved by training a certain type of memory.

Most IQ tests attempt to measure two types of intelligence--crystallized and fluid intelligence. Crystallized intelligence draws on existing skills, knowledge and experiences to solve problems by accessing information from long-term memory.

Fluid intelligence, on the other hand, draws on the ability to understand relationships between various concepts, independent of any previous knowledge or skills, to solve new problems. The research shows that this part of intelligence can be improved through memory training.

Tags: brain, plastic, nature, nurture

Flow of potassium ions in brain cells is key to sexual arousal

Wed, 04 Jun 2008 09:35:46 GMT

clipped by: wildcat

Clip Source: physorg.com

When it comes to sex, a female rat knows how to avoid a communication breakdown. To announce her sexual readiness, she will automatically arch her back, deflect her tail and stand rigid to allow an aroused male to mount. Now, Rockefeller University researchers have figured out the precise chemical and physical mechanism in a group of brain cells that controls this swayback posture, a reflex called lordosis that signals one of life’s most complex yet primitive instincts — the need for sex.

The group of cells that generates lordosis behavior resides deep in the brain in a structure called the hypothalamus. When an aroused male touches the flanks of a female, these cells determine whether the female will present her rump. “By way of these cells, the female controls sexual reproduction,” says lead researcher Donald Pfaff, head of the Laboratory of Neurobiology and Behavior. “That’s why these cells are so important.”

Tags: brain, potassium, ion, sexual arousal

Comprehension Climbs When You Slooooow Doooown

Fri, 09 May 2008 10:54:41 GMT

clipped by: wildcat
clipper's remarks: clipversity, where art though?

Clip Source: www.wired.com

It should take you two and a half seconds to read this sentence. Any faster and you won't absorb its meaning. The motor response of the retina, and the time it takes the image of a word to travel from the macula to the thalamus to the visual cortex for processing, limits the eye to about 500 words a minute. (That's peak efficiency; the average college student can expect a rate about half that.) "There is no such thing as speed reading," says Keith Rayner a cognitive psychologist at the University of Massachusetts-Amherst. "Not if your definition of reading is comprehending text." Studies show that fast readers fare worse than slower ones when questioned about the text. So, to get smarter, slow down. It's even OK to move your lips.

Tags: brain, reading, slowing down, comprehension