Language Structure… You’re Born with It

Humans are unique in their ability to acquire language. But how? A new study published in the Proceeding of the National Academy of Sciences shows that we are in fact born with the basic fundamental knowledge of language, thus shedding light on the age-old linguistic “nature vs. nurture” debate.

THE STUDY

While languages differ from each other in many ways, certain aspects appear to be shared across languages. These aspects might stem from linguistic principles that are active in all human brains. A natural question then arises: are infants born with knowledge of how the human words might sound like? Are infants biased to consider certain sound sequences as more word-like than others? “The results of this new study suggest that, the sound patterns of human languages are the product of an inborn biological instinct, very much like birdsong,” said Prof. Iris Berent of Northeastern University in Boston, who co-authored the study with a research team from the International School of Advanced Studies in Italy, headed by Dr. Jacques Mehler. The study’s first author is Dr. David Gómez.

BLA, ShBA, LBA

Consider, for instance, the sound-combinations that occur at the beginning of words. While many languages have words that begin by bl (e.g., blando in Italian, blink in English, and blusa in Spanish), few languages have words that begin with lb. Russian is such a language (e.g., lbu, a word related to lob, “forehead”), but even in Russian such words are extremely rare and outnumbered by words starting with bl. Linguists have suggested that such patterns occur because human brains are biased to favor syllables such as bla over lba. In line with this possibility, past experimental research from Dr. Berent’s lab has shown that adult speakers display such preferences, even if their native language has no words resembling either bla or lba. But where does this knowledge stem from? Is it due to some universal linguistic principle, or to adults’ lifelong experience with listening and producing their native language?

THE EXPERIMENT

These questions motivated our team to look carefully at how young babies perceive different types of words. We used near-infrared spectroscopy, a silent and non-invasive technique that tells us how the oxygenation of the brain cortex (those very first centimeters of gray matter just below the scalp) changes in time, to look at the brain reactions of Italian newborn babies when listening to good and bad word candidates as described above (e.g., blif, lbif).

Working with Italian newborn infants and their families, we observed that newborns react differently to good and bad word candidates, similar to what adults do. Young infants have not learned any words yet, they do not even babble yet, and still they share with us a sense of how words should sound. This finding shows that we are born with the basic, foundational knowledge about the sound pattern of human languages.

It is hard to imagine how differently languages would sound if humans did not share such type of knowledge. We are fortunate that we do, and so our babies can come to the world with the certainty that they will readily recognize the sound patterns of words–no matter the language they will grow up with.

(Image caption: The images show an early developmental stage of normal (top row) and BRCA1-deficient brains (bottom row). The imaged embryos show abundant proliferation of cell growth (red, first column) in both normal and BRCA1-deficient brains at this stage. However brains lacking BRCA1 exhibit high levels of cellular suicide (green, second column). The third column shows an overlay of the other columns. Credit: Courtesy of the Salk Institute for Biological Studies)

Scientists reveal potential link between brain development and breast cancer gene

Scientists at the Salk Institute have uncovered details into a surprising—and crucial—link between brain development and a gene whose mutation is tied to breast and ovarian cancer. Aside from better understanding neurological damage associated in a small percentage of people susceptible to breast cancers, the new work also helps to better understand the evolution of the brain.

The research, published this month in PNAS, shows that the gene known as BRCA1 has a significant role in creating healthy brains in mice and may provide a hint as to why some women genetically prone to breast cancer experience brain seizures.

"Previously, people associated mutations or deletions of BRCA1 with breast and ovarian cancer," says Inder Verma, a professor in Salk’s Laboratory of Genetics and American Cancer Society Professor of Molecular Biology. "Our paper goes beyond this link to explain the protective mechanism of BRCA1 in the brain."

Through a three–lab collaboration at the Salk Institute, which began over a water cooler conversation between adjacent lab researchers 10 years ago, the work has culminated in dramatic findings. The team found that eliminating BRCA1 in neural stems cells had profound effects: large swaths of brain were simply missing; the cortex, which typically has six layers, only developed two very rudimentary layers; the cerebellum, which is normally made up of many folds and creases, was almost completely smooth; and the olfactory bulb, which processes odor information, was severely disorganized and poorly developed. Neurons were dying rapidly shortly after forming, while ones that did last were often defective. In mouse models, this resulted in interference in balance, motor skills, and other core functions.

How exactly was the absence of BRCA1 leading to such a neural catastrophe? In a previous paper, the team showed that without the protein coded by the BRCA1 gene, DNA is not packaged properly, becoming fragile and more likely to break during DNA replication. In this new paper, the researchers reveal more about that mechanism, showing that without the protective ability of BRCA1, breaks in the DNA strands go unfixed, prompting the molecule ATM kinase to activate a cellular “suicide” pathway involving a protein called p53. This pathway helps to halt the replication of damaged cells and is important in cancer research.

"BRCA1 acts by conferring stability to the DNA and preventing it from breaking," says Carlos G. Perez–Garcia, a Salk researcher in the Molecular Neurobiology Lab. "BRCA1 is important for all healthy cells."

When the researchers eliminated both BRCA1 and p53, they found the neurons grew at a normal rate, but still disorderly, with cells pointed in the wrong direction.

"In this scenario, we recover a lot of neurons but there’s still a lot of abnormalities, such as cells that are sideways and pointed the wrong direction," says Gerald Pao, who, along with Quan Zhu and Perez–Garcia, is a primary contributor to the paper and Salk researcher.

This observation led the team to propose that BRCA1 has an additional role in assisting neurons in orienting: the gene acts on the centromere of DNA—essentially an anchor for the chromosome arms essential in cell replication—to tell the new cell in which direction to grow, providing guidance in developing the brain’s organized layers.

"It is remarkable that BRCA1 has such a significant effect on the brain, especially size. This work leads us to a better understanding of how to protect neurons," says Verma, who is also the Irwin and Joan Jacobs Chair in Exemplary Life Science. Because BRCA1 seems to regulate the centromere, studying the gene will help scientists to understand how mammalian brains have evolved over time.

"Now we have an explanation for why some patients with breast cancer also experienced brain seizures," adds Pao. This knowledge could potentially help identify breast cancer–susceptible patients predisposed to seizures and provide appropriate treatments.

Faster eye responses in Chinese people not down to culture

New research from University of Liverpool scientists has cast doubt on the theory that neurological behaviour is a product of culture in people of Chinese origin.

Scientists tested three groups – students from mainland China, British people with Chinese parents and white British people – to see how quickly their eyes reacted to dots appearing in the periphery of their vision.

These rapid eye movements, known as saccades, were timed in all of the participants to see which of them were capable of making high numbers of express saccades – particularly fast responses which begin a tenth of a second after a target appears.

The findings, published in the journal PLoS One, revealed that similar numbers of the British Chinese and mainland Chinese participants made high numbers express saccades, with the white British participants made far fewer. Culturally the British Chinese participants were similar to their white British counterparts and different to the mainland Chinese students.

Therefore in terms of eye movement patterns, Chinese ethnicity was more of a factor than culture. This is contrary to several previous reports from other research groups which looked at behaviour in Asian and white participants and concluded that culture explained behavioural differences between groups.

Neurophysiologist, Dr Paul Knox, from the University’s Institute of Ageing and Chronic Disease, led the study. He said: “Examining saccades from different populations is revealing a lot about underlying brain mechanisms and how we think.

"Many scientists believe that the eye movement patterns you develop are due to where you live – the books you read and the influence of your family, peers and community – your culture."

"Our research has shown that this cannot be the case, at least for saccade behaviour. What this leaves is the way we’re made, perhaps our genetics. And this may have a bearing on the way the brains in different groups react to injuries and disease."

All of the participants completed questionnaires which evaluated their cultural values. They then wore a headset and looked at a plain white board on which lights appeared. The headset measured the time it took for participants’ eyes to react to the lights as they appeared in different places on the board.

Twenty-seven percent of Chinese participants responded with high proportions of express saccades, similar to 22% of the British Chinese, but many more than the 10% of white British participants.

Dr Knox concluded: “From a situation where 80% of our understanding of neuroscience was derived from tests on US psychology undergraduates, we’re now showing how the human brain is not just amazingly complex in general, but also highly variable across the human population.”

(Image credit)

Scientists identify part of brain linked to gambling addiction

New research reveals that brain damage affecting the insula – an area with a key role in emotions – disrupts errors of thinking linked to gambling addiction.

The research, led by Dr Luke Clark from the University of Cambridge, was published on April 7 2014 in the journal PNAS.

During gambling games, people often misperceive their chances of winning due to a number of errors of thinking called cognitive distortions. For example, ‘near-misses’ seem to encourage further play, even though they are no different from any other loss. In a random sequence like tossing a coin, a run of one event (heads) makes people think the other outcome (tails) is due next; this is known as the ‘gambler’s fallacy’.

There is increasing evidence that problem gamblers are particularly prone to these erroneous beliefs. In this study, the researchers examined the neurological basis of these beliefs in patients with injuries to different parts of the brain.

“While neuroimaging studies can tell us a great deal about the brain’s response to complex events, it’s only by studying patients with brain injury that we can see if a brain region is actually needed to perform a given task,” said Dr Clark.

For the study, the researchers gave patients with injuries to specific parts of the brain (the ventromedial prefrontal cortex, the amygdala, or the insula) two different gambling tasks: a slot machine game that delivered wins and ‘near-misses’ (like a cherry one position from the jackpot line), and a roulette game involving red or black predictions, to elicit the gambler’s fallacy. For the control groups, they also had patients with injuries to other parts of the brain as well as healthy participants undergo the gambling tasks.

All of the groups with the exception of the patients with insula damage reported a heightened motivation to play following near-misses in the slot machine game, and also fell prey to the gambler’s fallacy in the roulette game.

Clark added: “Based on these results, we believe that the insula could be hyperactive in problem gamblers, making them more susceptible to these errors of thinking. Future treatments for gambling addiction could seek to reduce this hyperactivity, either by drugs or by psychological techniques like mindfulness therapies.”

Gambling is a widespread activity: 73% of people in the UK report some gambling involvement in the past year* and around 50% play games other than the National Lottery. For a small proportion of players (around 1-5%), their gambling becomes excessive, resulting in features seen in addiction. Problem gambling is associated with both debt and family difficulties as well as other mental health problems like depression.

Feelings of Failure, Not Violent Content, Foster Aggression in Video Gamers

The disturbing imagery or violent storylines of videos games like World of Warcraft or Grand Theft Auto are often accused of fostering feelings of aggression in players. But a new study shows hostile behavior is linked to gamers’ experiences of failure and frustration during play—not to a game’s violent content.

The study is the first to look at the player’s psychological experience with video games instead of focusing solely on its content. Researchers found that failure to master a game and its controls led to frustration and aggression, regardless of whether the game was violent or not. The findings of the study were published online in the March edition of the Journal of Personality and Social Psychology.

“Any player who has thrown down a remote control after losing an electronic game can relate to the intense feelings or anger failure can cause,” explains lead author Andrew Przybylski, a researcher at the Oxford Internet Institute at Oxford University, who said such frustration is commonly known among gamers as “rage-quitting.”

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Spinal Stimulation Helps Four Patients with Paraplegia Regain Voluntary Movement

Four people with paraplegia are able to voluntarily move previously paralyzed muscles as a result of a novel therapy that involves electrical stimulation of the spinal cord, according to a study funded in part by the National Institutes of Health and the Christopher & Dana Reeve Foundation. The participants, each of whom had been paralyzed for more than two years, were able to voluntarily flex their toes, ankles, and knees while the stimulator was active, and the movements were enhanced over time when combined with physical rehabilitation. Researchers involved in the study say the therapy has the potential to change the prognosis of people with paralysis even years after injury.

“When we first learned that a patient had regained voluntary control as a result of spinal stimulation, we were cautiously optimistic,” said Roderic Pettigrew, Ph.D., M.D., director of the National Institute of Biomedical Imaging and Bioengineering (NIBIB) at NIH, which provided support for the study. “Now that spinal stimulation has been successful in 4 out of 4 patients, there is evidence to suggest that a large cohort of individuals, previously with little realistic hope of any meaningful recovery from spinal cord injury, may benefit from this intervention.”

One of the most impressive and unexpected findings of the study is that two of the patients who benefited from the spinal stimulation had complete motor and sensory paralysis. In these patients, the pathway that sends information about sensation from the legs to the brain is disrupted, in addition to the pathway that sends information from the brain to the legs in order to control movement. The researchers were surprised by the outcome; they had assumed that at least some of the sensory pathway needed to be intact for the therapy to be effective.

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Don’t beat yourself up, you’ll live longer

Brandeis researchers explore the relationship between self-compassion and health

We all have stress in our lives, whether it’s a daily commute, workplace pressures or relationship troubles. But how we deal with that stress could impact our health and longevity.

In a recently published paper in Brain, Behavior and Immunity, Brandeis University researchers report they found a connection between a self-compassionate attitude and lower levels of stress-induced inflammation. The discovery could lead to new techniques to lower stress and improve health.

The paper was authored by psychology professor Nicolas Rohleder, with postdoctoral fellows Juliana Breines and Myriam Thoma, and graduate students Danielle Gianferante, Luke Hanlin and Xuejie Chen.

It’s long known that psychological stress can trigger biological responses similar to the effects of illness or injury, including inflammation. While regulated inflammation can help stave off infection or promote healing, unregulated inflammation can lead to cardiovascular disease, cancer and Alzheimer’s.

Self-compassion describes behaviors such as self-forgiveness or, more colloquially, cutting yourself some slack. A person with high levels of self-compassion may not blame themselves for stress beyond their control or may be more willing to move on from an argument, rather than dwelling on it for days.

To understand the connection between self-compassion and inflammatory responses to stress, Rohleder and his team asked 41 participants to rank their levels of self-compassion. The participants ranked their agreement to statements such as, “I try to be understanding and patient toward aspects of my personality I do not like” and “I’m disapproving and judgmental about my own flaws and inadequacies.”

Then, the participants took one stress test a day for two days and their levels of interleukin-6 (IL-6), an inflammatory agent linked to stress, were recorded before and after each test. After the first stress test, participants with higher self-compassion had significantly lower levels of IL-6.

On the second day, Rohleder and his team found something unexpected. Those with low self-compassion had higher base levels of IL-6 before the test, suggesting that they may have been carrying the stress they experienced the day before.

“The high responses of IL-6 on the first day and the higher baseline levels on the second day suggest that people with low self-compassion are especially vulnerable to the adverse effects of this kind of stress,” Rohleder says.

The research illustrates how easy it is for stress to build over time and how a seemingly small daily stressor, such as traffic, can impact a person’s health if they don’t have the right strategies to deal with it.

“Hopefully, this research can provide more effective ways to cope with stress and reduce disease, not only by relieving negative emotions but by fostering positive ideas of self compassion,” Rohleder says.

Genes increase the stress of social disadvantage for some children

Genes amplify the stress of harsh environments for some children, and magnify the advantage of supportive environments for other children, according to a study that’s one of the first to document how genes interacting with social environments affect biomarkers of stress.

"Our findings suggest that an individual’s genetic architecture moderates the magnitude of the response to external stimuli—but it is the environment that determines the direction" says Colter Mitchell, lead author of the paper and a researcher at the University of Michigan Institute for Social Research (ISR).

The study, published today in the Proceedings of the National Academy of Sciences, uses telomere length as a marker of stress. Found at the ends of chromosomes, telomeres generally shorten with age, and when individuals are exposed to disease and chronic stress, including the stress of living in a disadvantaged environment.

For the study, Mitchell and colleagues used telomere samples from a group of 40 nine-year-old boys from two very different environments – one nurturing and the other harsh. Those in the nurturing environment came from stable families, with nurturing parenting, good maternal mental health, and positive socioeconomic conditions, while those in the harsh environment experienced high levels of poverty, harsh parenting, poor maternal mental health, and high family instability.

For those children with heightened sensitivity in the serotonergic and dopaminergic genetic pathways compared to other children, telomere length was shortest in a disadvantaged environment, and longest in a supportive environment.