Small but distinct differences among species mark evolution of human brain

Date:  November 24, 2017

Source:  Yale University

Summary:

The most dramatic divergence between humans and other primates can be found in the brain, the primary organ that gives our species its identity. However, all regions of the human brain have molecular signatures very similar to those of our primate relatives, yet some regions contain distinctly human patterns of gene activity that mark the brain's evolution and may contribute to our cognitive abilities, a new study has found.

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First-ever fossilized dinosaur brain tissue discovered

October 28, 2016

by Chuck Bednar


Paleontologists have confirmed the discovery of the first ever fossilized dinosaur brain tissue, a 130-million-year-old specimen that was discovered in the UK and which resembled a tiny brown pebble, according to new research reported Thursday by the Geological Society of London.

According to the Guardian and the New York Times, the brain tissue was originally discovered in East Sussex, England by an amateur fossil hunter named Jamie Hiscocks in 2004. The fossil was a cast of the dinosaur’s brain cavity which appeared to contain mineral tissues, the reports said. Forensic analysis of the specimen confirmed the presence of blood vessels and capillaries, tissues from the outer cortex, and the tough tissues that surround the brain itself and help keep it in place (meninges). The tissues were said to be similar to those found in modern birds and crocodiles.

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Scientists establish first map of the sea lion brain

Date: April 27, 2016

Source: Vanderbilt University

Summary:Despite considerable evidence for the California sea lion's intelligence, very little is known about how their brain is organized. Now, a team of neuroscientists has taken an important step toward uncovering this mystery by conducting the first comprehensive study of the California sea lion's central nervous system, concentrating on the somatosensory system, which is concerned with conscious perception of touch, pressure, pain, temperature, position and vibration.

Rio is a California sea lion who can solve IQ tests that many people have trouble passing. In fact, she is so smart that scientists at the Long Marine Lab at the University of California, Santa Cruz designed a series of tests that prove she is the first animal besides humans that can use basic logic (If A=B and B=C then A=C).

Rio's display of intelligence is less surprising when you consider the fact that she is a member of one of only four groups of animals that have evolved extremely large brains (weighing more than 1.5 pounds). Along with seals and walruses, she is part of a group of fin-footed, semiaquatic marine mammals called pinnipeds. The other large-brained groups are humans, elephants and cetaceans (whales and dolphins).

Read on ...

Monkey skull study suggests brain evolved in spurts

February 9, 2016 by Bob Yirka 

Credit: Leandro Aristide, doi: 10.1073/pnas.1514473113

(Phys.org)—A small team of researchers from Brazil and Argentina has found via skull analysis and modeling that a kind of new-world monkey appears to have undergone changes in individual parts of its brain during evolutionary periods which led to advances in cognitive development. In their paper published in Proceedings of the National Academy of Sciences, the team describes their study and results and why they believe what they found might apply to humans as well.

For many years, researchers believed that superior intelligence in humans was attributable to our brain size—that the large size of our brain relative to the size of the rest of our body was what set us apart. But subsequent studies found that other animals had ratios that were even more pronounced than ours, suggest thing it must be something else. In this new study, the researchers propose that it was changes to the size of certain parts of the brain that led to increases in cognitive abilities, and that it happened in spurts.

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3D compass found in the brain

Date:

December 3, 2014

Source:

Weizmann Institute of Science

Summary:

The neurons that help us know where we’re going have been discovered by researchers. Working with bats, which move in three dimensions, the team found that bats’ brains contain a sort of 3D compass, enabling them to orient themselves in space. They believe that the brains of non-flying mammals – including humans – also have the compass.

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Brain of world's first known predators discovered

Date:

July 16, 2014

Source:

University of Arizona

Summary:

Scientists have found the fossilized remains of the brain of the world's earliest known predators, from a time when life teemed in the oceans but had not yet colonized the land. The discovery reveals a brain much simpler than those known in some of the animal's prey and helps answer questions surrounding the evolution of arthropods.

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What bat brains might tell us about human brains

Date:
March 4, 2014

Source:
Georgetown University Medical Center

Summary:
Could a new finding in bats help unlock a mystery about the human brain? Likely so, say researchers who have shown that a small region within the amygdala, an almond-shaped structure in the brains of all mammals, is responsible for producing emotional calls and sounds. They say this discovery might be key to locating a similar center in human brains.


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Brain has specific radar for snakes, study shows - via Herp Digest

Saturday, November 2, 2013 11:37AM EDT 

(AFP) - Ever wonder why snakes inspire such fear? A new study on monkeys out Monday says the brain has specific cells that fire off rapid warnings when confronted with slithery danger.

Certain neurons respond "selectively" to images of snakes, and they outpace comparable neurons that react to visuals of faces, hands or geometric shapes, the researchers said.

The report in the Proceedings of the National Academy of Sciences offers new evidence to support the notion that primates evolved keen vision skills so they could survive the threats snakes pose in the jungle.

"It really strengthens the argument that snakes are very important for the evolution of primates," lead co-author Lynne Isbell, a professor in the anthropology department at the University of California Davis, told AFP.

"Snakes elicited the strongest, fastest responses," said the study, co-authored by Quan Van Le of the University of Toyama and researchers at the University of Brasilia.

The research was done using two young macaque monkeys that were born on a national monkey farm in Japan.

Researchers said they believe the monkeys had no chance to encounter snakes prior to the experiment.

Scientists surgically implanted micro-electrodes in a part of the brain known as the pulvinar, which is involved in visual attention and the fast processing of threatening images.

Then they showed the monkeys various color images on a computer screen, including snakes in various positions, threatening monkey faces, pictures of monkey hands and simple shapes like stars or squares.

Seeing a snake caused the brain to fire off rapid fear responses that were unparalleled by those observed in reaction to faces, hands or shapes.

Researchers found that of about 100 neurons that fired off when presented with at least one of the image types, 40 percent had the largest response to snakes.

That was the biggest group, followed by almost 29 percent that were superior at responding to faces.

While researchers have long known that primates have an uncanny ability to see snakes even in cluttered surroundings, the latest data adds a new answer to the question of why.

Whether snakes were eating primates, or simply delivering lethal bites, the evolutionary process to boost survival in their midst likely began tens of millions of years ago, said Isbell.

Previous research has even shown that some primates, such as the Malagasy lemurs of Madagascar where there are no venomous snakes, do not express fear of them they way other apes and monkeys do.

"Snakes are largely responsible for the origin of primates. Vision is what separates primates from other mammals. A lot of the structures in our brain are devoted to vision," said Isbell, who wrote a book on the topic in 2009 called "The Fruit, the Tree, and the Serpent: Why We See So Well."

"I pulled together indirect evidence," she told AFP.

"Here is the first time that somebody has come along and actually tested some of the predictions in the book and I am really gratified that it was supported."

While the study included only two monkeys, future research could focus on responses to other predators by primates, as well as the potential for learning more about how the human brain responds, Isbell said.

Susan Mineka, a professor of clinical psychology at Northwestern University and an expert on primates, described the work as "absolutely fascinating" and "really important."

She said one potential weakness was that the research team seemed unable to say for certain whether the monkeys studied had ever encountered a snake.

"It is too bad that they didn't also document what these monkeys' behavioral responses to snakes were like," Mineka added.

"We have known that many species of monkeys either have an innate fear of snakes or pick up a fear of snakes very readily. This provides a probable mechanism. That has been a huge question in the literature."

Part of Brain That Makes Humans and Primates Social Creatures May Play Similar Role in Carnivores

Oct. 8, 2013 — The part of the brain that makes humans and primates social creatures may play a similar role in carnivores, according to a growing body of research by a Michigan State University neuroscientist.

In studying spotted hyenas, lions and, most recently, the raccoon family, Sharleen Sakai has found a correlation between the size of the animals' frontal cortex and their social nature.

In her latest study, Sakai examined the digitally recreated brains of three species in the Procyonid family -- the raccoon, the coatimundi and the kinkajou -- and found the coatimundi had the largest frontal cortex. The frontal cortex is thought to regulate social interaction, and the coatimundi is by far the most social of the three animals, often living in bands of 20 or more.

The study, funded by the National Science Foundation, is published in the research journal Brain, Behavior and Evolution.

"Most neuroscience research that looks at how brains evolve has focused primarily on primates, so nobody really knows what the frontal cortex in a carnivore does," said Sakai, professor of psychology. "These findings suggest the frontal cortex is processing social information in carnivores perhaps similar to what we've seen in monkeys and humans."

Sakai did the most recent study in her neuroscience lab with Bradley Arsznov, a former MSU doctoral student who's now an assistant professor of psychology at Minnesota State University. 

Her latest study was based on the findings from 45 adult Procyonid skulls acquired from university museum collections (17 coatimundis, 14 raccoons and 14 kinkajous). The researchers used computed tomography, or CT scans, and sophisticated software to digitally "fill in" the areas where the brains would have been.

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First look into workings of the Neanderthal brain

Editorial: "Gene breakthrough shows Neanderthals in new light"

BONES. That is all the passing millennia have left us of the Neanderthals and the more elusive Denisovans. Until recently, the main insights gleaned from these bones have been physical: what our cousins might have looked like, for instance, and how they moved. But cutting-edge genetic science is changing that.

We can now see, for the first time, which genes are switched on in humans but were not in Neanderthals and Denisovans, and vice versa. The findings point to subtle differences between our brain structure and function, and theirs.

The research, presented last week at the Society for Molecular Biology and Evolution meeting in Chicago, reveals that after our ancestors split from Neanderthals and Denisovans, they evolved differences in genes connected with cognitive abilities. Many of those genes are associated with mental disorders in modern humans.

Working out which genes ...

http://www.newscientist.com/article/mg21929264.400?cmpid=NLC%7CNSNS%7C2013-1807-GLOBAL&utm_medium=NLC&utm_source=NSNS&

Brain Candy: Chemical Turns Rats into M&M Eating Machines

A part of the brain usually associated with movement may also control our responses to rewards, according to new research that finds stimulation of the region with an opium-like chemical can make rats gorge on M&M candies.

The brain naturally produces opioids, or chemicals with similarities to the drug. One of these, enkephalin, induced hungry rats to pounce on chocolate treats faster the more of the chemical they produced, researchers report online today (Sept. 20) in the journal Current Biology.

When scientists dosed the rats with a big jolt of enkephalin in a brain region called the neostriatum, the rats became eating machines, downing the equivalent of a 150-pound (68 kilogram) person eating 7 to 8 pounds (3.1 to 3.5 kg) of M&Ms in an hour, said study researcher Alexandra DiFeliceantonio.

Continued:  http://www.livescience.com/23345-brain-chemical-triggers-overeating.html

2,600-Year-Old Brain Found in England, in Remarkably Fresh Condition

Archeologists working in York in the United Kingdom discovered a remarkably well-preserved human brain that was over 2,500 years old.

Found by UK researchers, the brain was found in a decapitated skull aged 2,684 years. The brain is the oldest found brain in Europe or Asia, and is thought to be the best-preserved in the world.

The finding is particularly astonishing because, even when left on a counter in a chilled mortuary facility, brains tend to degrade quickly into liquid. This one, however, had the consistency of tofu, and had none of the distinctive smell so often associated with dead corpses.

Though it is difficult to ascertain cause of death after so many years, the damage to the neck vertebrae was consistent with a hanging. Sonia O'Connor and her colleagues believe that the person was hanged, and then the skull was decapitated.

Interestingly, the way that the body died worked against the preservation of the brain. The separation of the head from the rest of its body would have opened it up to immediate infection from bacteria.

The study was published in the Journal of Archeological Science.

Continued:  http://www.medicaldaily.com/articles/11577/20120817/brain-archeology-well-preserved-heslington-england.htm

What Blind Monkeys Might 'See'

(ISNS) -- When the area of the brain responsible for processing vision is destroyed, does some visual ability still remain? The answer is yes, surprising even to human patients who have experienced this condition, but researchers are looking to monkeys to determine what, and how much, exists.

The long-documented phenomenon of blindsight has shown that though much is lost, much can abide. Even though a blindsight patient doesn't consciously know it, his or her visual attention is still being guided by stimuli like movement in their "blind" field, according to Laurent Itti, a researcher at the University of Southern California in Los Angeles who studies blindsight.

A medical officer attending to soldiers wounded in World War I had first described blindsight as a phenomenon resulting from wounds in the occipital lobe. This is the area of the brain that contains most of the visual cortex, which processes visual signals. The term "blindsight" itself was coined in the 1970s.

Continued:  http://www.livescience.com/22485-what-blind-monkeys-might-see.html