Babies Learn the Smell of Mum

Researchers show for the first time that a mammal begins to suckle its mother’s milk through a learned response built on learning her unique combination of smells. When it is born, the newborn is exposed to the smell of its mother’s amniotic fluid and the baby then responds to those smells to feed.

Prevailing thought has been that pheromones –chemicals that trigger an innate behavior – drove the suckling response as an automatic behavior. The new work determines that, in mice, the smells must be learned before the behavior can occur.

Suckling is a critical step for survival in mammals, which are defined by giving birth to offspring that need to feed from their mother’s milk. The newborn must begin to feed soon after birth or it will die. It is a crucial, defining behavior in mammals and offers researchers an opportunity to investigate the biology of instinct.

Chewing Ability Linked to Reduced Dementia Risk

The population is aging, and the older we become the more likely it is that we risk deterioration of our cognitive functions, such as memory, decision-making and problem solving. Research indicates several possible contributors to these changes, with several studies demonstrating an association between not having teeth and loss of cognitive function and a higher risk of dementia.

One reason for this could be that few or no teeth makes chewing difficult, which leads to a reduction in the blood flow to the brain. However, to date there has been no direct investigation into the significance of chewing ability in a national representative sample of elderly people.  

Now a team comprised of researchers from the Department of Dental Medicine and the Aging Research Center (ARC) at Karolinska Institutet and from Karlstad University in Sweden have looked at tooth loss, chewing ability and cognitive function in a random nationwide sample of 557 people aged 77 or older. They found that those who had difficulty chewing hard food such as apples had a significantly higher risk of developing cognitive impairments. This correlation remained even when controlling for sex, age, education and mental health problems, variables that are often reported to impact on cognition. Whether chewing ability was sustained with natural teeth or dentures also had no bearing on the effect.

The results are published in the Journal of the American Geriatrics Society (JAGS).

A molecular scissor related to Alzheimer’s Disease

An international research team led by the Spanish National Research Council (CSIC) and researchers from Kiel University revealed the atomic-level structure of the human peptidase enzyme meprin ß (beta). The enzyme is related to inflammation, cancer and Alzheimer’s Disease and is involved in cellular proliferation and differentiation. The knowledge of the enzyme structure will allow for the development of a new medication type different from those known up to now. The study was published in the current issue of the journal “Proceedings of the National Academy of Sciences”.

“Now that we know how meprin ß looks, how it works and how it relates to diseases, we can search for substances that stop its enzyme activities when they become harmful”, explains Xavier Gomis-Rüth, researcher at the Molecular Biology Institute of Barcelona, who led the project. Meprin ß is an enzyme that is anchored in the outer wall of cells. Its normal function in the human metabolism is to cut off certain proteins, e.g. growth factors, that are also anchored in the cell wall. In this way meprin ß releases protein fragments into the environment surrounding the cells – a natural and normal process, as long as it occurs at a certain intensity. However, under specific circumstances, meprin ß may function abnormally, and, for example, releases too many protein fragments. The protein pieces than overdo their natural task in the cell surroundings, causing disorder in the human body. Such disorder typically occurs when inflammation, cancer or Alzheimer’s Disease get started.

NYU researchers find electricity in biological clock

Biologists from New York University have uncovered new ways our biological clock’s neurons use electrical activity to help keep behavioral rhythms in order. The findings, which appear in the journal Current Biology, also point to fresh directions for exploring sleep disorders and related afflictions.

“This process helps explain how our biological clocks keep such amazingly good time,” said Justin Blau, an associate professor of biology at NYU and one of the study’s authors.

Blau added that the findings may offer new pathways for exploring treatments to sleep disorders because the research highlights the parts of our biological clock that “may be particularly responsive to treatment or changes at different times of the day.”

Head injury turns man into musical savant

Less than six years ago, Derek Amato had only mediocre guitar skills. But after suffering a concussion – and never having a lesson – he became a piano-playing sensation.

Is there a savant inside all of us?

Researchers have discovered a way to generate new human neurons from another type of adult cell found in our brains. The discovery, reported in the October 5th issue of Cell Stem Cell, a Cell Press publication, is one step toward cell-based therapies for the treatment of neurodegenerative diseases, such as Alzheimer’s and Parkinson’s.

Yale scientists explain how ketamine vanquishes depression within hours

Many chronically depressed and treatment-resistant patients experience immediate relief from symptoms after taking small amounts of the drug ketamine. For a decade, scientists have been trying to explain the observation first made at Yale University.

Today, current evidence suggests that the pediatric anesthetic helps regenerate synaptic connections between brain cells damaged by stress and depression, according to a review of scientific research written by Yale School of Medicine researchers and published in the Oct. 5 issue of the journal Science.

Ketamine works on an entirely different type of neurotransmitter system than current antidepressants, which can take months to improve symptoms of depression and do not work at all for one out of every three patients.  Understanding how ketamine works in the brain could lead to the development of an entirely new class of antidepressants, offering relief for tens of millions of people suffering from chronic depression.

“The rapid therapeutic response of ketamine in treatment-resistant patients is the biggest breakthrough in depression research in a half century,” said Ronald Duman, the Elizabeth Mears and House Jameson Professor of Psychiatry and Professor of Neurobiology.

Nearly 100 years after a British neurologist first mapped the blind spots caused by missile wounds to the brains of soldiers, Perelman School of Medicine researchers at the University of Pennsylvania have perfected his map using modern-day technology. Their results create a map of vision in the brain based upon an individual’s brain structure, even for people who cannot see. Their result can, among other things, guide efforts to restore vision using a neural prosthesis that stimulates the surface of the brain. The study appears in the latest issue of Current Biology, a Cell Press journal.

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Fast-food logos burned into pleasure center of children’s brains

A study has found that fast-food logos are branded into the minds of children at an early age, perhaps fueling the West’s obesity epidemic. The study showed children 60 logos from popular food brands and 60 logos from popular non-food brands. Researchers found that, when shown images of fast-food brands, the parts of kids’ brains linked with pleasure and appetite lit up. This is concerning because marketers tap into those portions of the brain long before children develop self-control, and most foods marketed to kids are high in calories, sugar, sodium, and fat.

Finches flirt unwisely if they can only use their left eyes

A patch over a male Gouldian finch’s right eye works like beer goggles, though the bird doesn’t need booze to flirt unwisely. If limited to using his left eye when checking out possible mates, he risks making really stupid choices.

Gouldian finches have caps of black, red or yellow feathers on their heads. In nature, the birds prefer to mate with partners with the same cap color. Yet black-headed males rendered temporarily left-eyed by a tiny removable eye patch flirted as readily with red-heads as with black-heads, says cognitive ecologist Jennifer Templeton of Knox College in Galesburg, Ill. That’s not smart because daughters typically fail to survive when Gouldian finches mate outside their cap color.

Also the male himself “becomes less attractive,” Templeton says. When the bird’s right eye was covered, he sang, bowed and posed less during his attempts at courtship. Some left-eyed males didn’t manage to make up their minds at all, but “just hopped around randomly,” Templeton says.

[Full article] In the eye of the beholder: visual mate choice lateralization in a polymorphic songbird