Posts tagged psychology
Posts tagged psychology
In 1979 China instituted the one-child policy, which limited every family to just one offspring in a controversial attempt to reduce the country’s burgeoning population. The strictly enforced law had the desired effects: in 2011 researchers estimated that the policy prevented 400 million births. In a new study in Science, researchers find that it has also caused China’s so-called little emperors to be more pessimistic, neurotic and selfish than their peers who have siblings.
Psychologist Xin Meng of the Australian National University in Canberra and her colleagues recruited 421 Chinese young adults born between 1975 and 1983 from around Beijing for a series of surveys and tests that evaluated a variety of psychological traits, such as trustworthiness and optimism. Almost all the participants born after 1979 were only children compared with about one fifth of those born before 1979. The study participants born after the policy went into effect were found to be both less trusting and less trustworthy, less inclined to take risks, less conscientious and optimistic, and less competitive than those born a few years earlier.
“Because of the one-child policy, parents are less likely to teach their child to be imaginative, trusting and unselfish,” Meng says. Without siblings, she notes, the need to share may not be emphasized, which could help explain these findings.
Only children in other parts of the world, however, do not show such striking differences from their peers. Toni Falbo, a social psychologist at the University of Texas at Austin, who was not involved in the study, suggests that larger social forces in China also probably contributed to these results. “There’s a lot of pressure being placed on [Chinese] parents to make their kid the best possible because they only had one,” Falbo says. These types of pressures could harm anyone, even if they had siblings, she says.
Whatever its cause, the personality profile of China’s little emperors may be troubling to a nation hoping to continue its ascent in economic prosperity. The traits marred by the one-child policy, the study authors point out, are exactly those needed in leaders and entrepreneurs.
If bats ever used a cell phone, they could forgo the version with caller ID: The mammals can identify each other by their voices, a new study says.
Bats aren’t the only mammals to use voice recognition—people do it, too. Even in the days before caller ID, a simple “Hi, it’s me,” from a close friend or loved one was usually enough to figure out who’s on the other end. Recognizing a person by voice, however, requires previous knowledge: We can’t identify a stranger on the phone by voice alone because we have never met them before.
People can, however, discriminate between a familiar voice and an unfamiliar one, even if they’ve never met the other person. We can also distinguish between two individuals by voice alone even if we’ve never met them before.
Hanna Kastein and colleagues at the University of Veterinary Medicine in Hannover, Germany, wanted to know whether bats could perform these same tasks.
“Bats are totally interesting mammals to study voice perception since they are dependent on their vocalizations for orientation and communication due to their nocturnal lifestyle. In addition, they are socially living animals that frequently communicate acoustically with other members of their species,” Kastein said.
Besides their social lifestyles, bats and people share a number of physical characteristics. Both produce sounds using a combination of the larynx, vocal cords, and nasal cavities. These structures work together with an animal’s physical makeup to produce an individual’s unique voice.
“In stressful situations, voices become higher pitched, or ‘squeaky,’ in bats as in humans. Also, each individual bat has a slightly different morphology, and thus its voice sounds different from any other individual, just as voices in humans differ individually,” Kastein said.
You Had Me at Hello
Kastein and colleagues wanted to know whether bats could use vocal calls to identify individuals with which they shared a roost, and whether they could use these same calls to distinguish between two different individuals.
The researchers worked with the greater false vampire bat (Megaderma lyra) because the species has a rich array of calls that it uses in several contexts.
The team observed two groups of bats kept in separate artificial roosts for two months. They hypothesized that bats that had the most body contact while roosting would form the closest relationships. Kastein and colleagues then recorded various vocal calls from both groups of bats.
When Kastein played the recording of a vocal call over a loudspeaker, bats in both roosts universally turned their heads toward the speaker regardless of whether the call was from a bat with which they had close body contact, a bat from the same roost, or a bat from the other roost.
Given that the artificial roosts had much lower rates of vocal calls, due to the lack of stimuli, the researchers thought that this response could be due to the novelty of hearing any type of vocalization.
So the team did a second set of experiments in which they had a bat listen to the call of their “friend” until the call didn’t create any type of behavioral response, such as turning the head. This means the listening bat had become habituated to the call, according to the study, published recently in the journal Animal Cognition.
Then, the scientists alternated playing a vocalization of the bat friend with that of an unfamiliar bat. The listening bats were significantly more likely to turn their heads toward the call of their friend—indicating both that they recognized their friend and that they could distinguish between individual vocalizations.
“In our study, we found that the … false vampire bat is able to discriminate between different voices, including both known or unknown individuals,” Kastein noted.
“However, to what extent bats are able to label an unknown bat as unknown, we cannot say.” She suspects that in real life, recognizing other bats by their voices is aided by smell and, to a lesser extent, vision.
Consider a failed murder attempt. Or a simple mistake that causes another to die. Is one of these more acceptable than the other?
Neuroscientists don’t pretend to hold the answers as to how people know what is right and what is wrong. But studies show individual biology may influence the ways people process the actions of others.
It turns out we judge others not only for what they do, but also for what we perceive they are thinking while they do it.
Consider the following scenario: Grace and Sally are touring a chemical factory when Grace decides to grab a cup of coffee. Sally asks Grace to pour her a cup as well. Grace spots a container of white powder next to the coffee maker and, knowing that her friend takes sugar in her coffee, she pours some into Sally’s cup. As it turns out, the powder is poison, and Sally dies after a few sips.
Most of us would understand and maybe forgive Grace for accidentally poisoning — or even killing — her friend. But what would you think of Grace if you were to learn that she had a hunch that the powder was toxic, yet decided to add it to her friend’s cup anyway?
“Often, what determines moral blame is not what the outcome is, but what [we think] is going on in the mind of the person performing the act,” says Rebecca Saxe, a neuroscientist at the Massachusetts Institute of Technology who studies how the brain casts judgment.
Scientists are learning the ways the brain responds when we attempt to determine right from wrong. Ultimately, they hope such information will help show how the brain processes difficult situations.
What was she thinking?
One way scientists study how we make right-or-wrong judgments is to look at brain regions that are most active when people attempt to interpret the thoughts of others.
In some studies, participants read stories about characters that either accidentally or intentionally cause harm to others while scientists use functional magnetic resonance imaging (fMRI) to track how brain activity changes. Such studies show that thinking about another’s thoughts increases the activity of nerve cells in a brain region known as the right temporo-parietal junction located behind the right ear.
As it turns out, some of these cells respond differently when presented with an intentional harm versus an accident. By zeroing in on the distinct patterns of activity in these cells, Saxe’s group discovered that they could accurately predict how forgiving the participants would be.
“People who say accidents are forgivable have really different [activity] patterns” than those less willing to overlook the unintentional harm, Saxe says.
Thinking about harm
Neuroscientists also study how people respond when asked how they themselves would act in morally challenging scenarios.
In one popular moral dilemma scenario, scientists ask participants to imagine the following: A runaway train is barreling down on five people. The only way to save these people is to hit a switch that would redirect the train onto tracks where it will kill only one person. Would you hit the switch?
What if, instead, you had to push a man off of a bridge to stop the train, knowing that doing so will kill him but save the lives of the others?
Studies ran these scenarios by people with damage to the ventromedial prefrontal cortex — a region believed to be involved in the processing of emotions — and those without damage. Both groups equally support the decision to hit the switch to redirect the train to save more lives.
However, those with damage to the ventromedial prefrontal cortex are much more likely to endorse pushing the man in front of the train, a more direct and personal harm. These studies, led by neuroscientist Antonio Damasio of the University of Southern California, suggest the important role of emotion in the generation of such judgments.
To test how important the ventromedial prefrontal cortex is when we judge the actions of others, Damasio along with neuroscientist Liane Young of Boston asked a small group of people with damage to this region to evaluate variations of the Grace and Sally story.
When told that Grace deliberately puts powder she believes is toxic into Sally’s cup, only to later learn the powder was sugar, healthy adults regularly condemn Grace’s failed attempt to harm her friend. However, people with ventromedial prefrontal cortex damage shrug off Grace’s action. As they see it, as long as Sally survives, Grace’s actions are no big deal.
Damasio says these results, along with others, reveal the role of the ventromedial prefrontal cortex and emotion in evaluating harmful intent.
That’s not fair
There is also evidence that changes in the chemistry of the brain influence how we behave when others treat us unfairly.
To measure how changes in brain chemistry affect people’s reactions to unfairness, University College London neuroscientist Molly Crockett and others gave study participants a drink to drive down levels of the neurotransmitter serotonin in the brain before asking them to play the ultimatum game.
In the ultimatum game, participants are paired with strangers they are told have been given a lump sum of money to share with them. The stranger determines how to divvy up the money, and proposes a split to the participant. The participant decides whether or not to accept the stranger’s offer. If the participant accepts, both players walk away with some money. However, a participant may reject the offer, believing it to be unfair, leaving both players empty-handed. Crockett found that people with lower levels of serotonin were more likely than others to reject offers they deemed to be unfair.
When the scientists examined the brain activity of participants with depleted serotonin levels as they accepted or rejected the offers, they found that rejecting offers led to increased activity in the dorsal striatum — a region involved in processing reward. Crockett says the findings suggest that dips in serotonin can shift people’s motivations to punish unfairness. For instance, when you deplete serotonin, people who are normally more forgiving may become happier with revenge, she says.
Crockett notes that serotonin levels may fluctuate when people are hungry or stressed. The findings illustrate how individual differences in biology might influence the way people view, and respond to, the actions of others.
An optical illusion can change the implicit biases of Caucasian people against people with darker skin, according to a study published in the August 2013 edition of Cognition.
The research, a collaboration between Royal Holloway University of London, the Central European University in Budapest and Radboud University Nijmegen in the Netherlands, analyzed the implicit racial biases of 34 Caucasian participants, then subjected them to something called the Rubber Hand Illusion, where they watched a rubber hand being touched by a paintbrush as they felt their own hand being stimulated out of sight. The illusion creates the sense that the fake hand is part of the subject’s body, even when it’s of a completely different skin color.
The more the participants felt like the darker skinned fake hand was their own, the less racist they came off in a second implicit bias test.
In another test, participants underwent the same process, but some saw a white hand, while others saw a dark hand. The implicit bias test showed that the opinions of those who saw the white hand didn’t change, while again those who felt ownership of the darker hand felt less racial bias.
“Across two experiments, the more intense the participants’ illusion of ownership over the dark-skinned rubber hand, the more positive their implicit racial attitudes became,” the authors write.
“It comes down to a perceived similarity between white and dark skin,” lead author Lara Maister of Royal Holloway University of London said in a press statement. “The illusion creates an overlap, which in turn helps to reduce negative attitudes because participants see less difference between themselves and those with dark skin.”
The study suggests that racial biases aren’t necessarily cemented by adulthood, but that they can be altered. “Changes in body-representation may therefore constitute a core, previously unexplored, dimension that in turn changes social cognition processes,” the authors write. They suggest that future research into different social groups and stereotypes could expand on their work, since this research only explored the attitudes of white individuals.
Patients with treatment-resistant major depression saw dramatic improvement in their illness after treatment with ketamine, an anesthetic, according to the largest ketamine clinical trial to-date led by researchers from the Icahn School of Medicine at Mount Sinai. The antidepressant benefits of ketamine were seen within 24 hours, whereas traditional antidepressants can take days or weeks to demonstrate a reduction in depression.
The research will be discussed at the American Psychiatric Association meeting on Monday, May 20, 2013 at 12:30 pm in the Press Briefing Room at the Moscone Center in San Franscico.
Led by Dan Iosifescu, MD, Associate Professor of Psychiatry at Mount Sinai; Sanjay Mathew, MD, Associate Professor of Psychiatry at Baylor College of Medicine; and James Murrough, MD Assistant Professor of Psychiatry at Mount Sinai, the research team evaluated 72 people with treatment-resistant depression—meaning their depression has failed to respond to two or more medications—who were administered a single intravenous infusion of ketamine for 40 minutes or an active placebo of midazolam, another type of anesthetic without antidepressant properties. Patients were interviewed after 24 hours and again after seven days. After 24 hours, the response rate was 63.8 percent in the ketamine group compared to 28 percent in the placebo group. The response to ketamine was durable after seven days, with a 45.7 percent response in the ketamine group versus 18.2 percent in the placebo group. Both drugs were well tolerated.
“Using midazolam as an active placebo allowed us to independently assess the antidepressant benefit of ketamine, excluding any anesthetic effects,” said Dr. Murrough, who is first author on the new report. “Ketamine continues to show significant promise as a new treatment option for patients with severe and refractory forms of depression.”
Major depression is caused by a breakdown in communication between nerve cells in the brain, a process that is controlled by chemicals called neurotransmitters. Traditional antidepressants such as selective serotonin reuptake inhibitors (SSRIs) influence the activity of the neurotransmitters serotonin and noreprenephrine to reduce depression. In these medicines, response is often significantly delayed and up to 60 percent of people do not respond to treatment, according to the U.S Department of Health and Human Services. Ketamine works differently than traditional antidepressants in that it influences the activity of the glutamine neurotransmitter to help restore the dysfunctional communication between nerve cells in the depressed brain, and much more quickly than traditional antidepressants.
Future studies are needed to investigate the longer term safety and efficacy of a course of ketamine in refractory depression. Dr. Murrough recently published a preliminary report in the journal Biological Psychiatry on the safety and efficacy of ketamine given three times weekly for two weeks in patients with treatment-resistant depression.
“We found that ketamine was safe and well tolerated and that patients who demonstrated a rapid antidepressant effect after starting ketamine were able to maintain the response throughout the course of the study,” Dr. Murrough said. “Larger placebo-controlled studies will be required to more fully determine the safety and efficacy profile of ketamine in depression.”
The potential of ketamine was discovered by Dennis S. Charney, MD, Anne and Joel Ehrenkranz Dean of the Icahn School of Medicine at Mount Sinai, and Executive Vice President for Academic Affairs of The Mount Sinai Medical Center, in collaboration with John H. Krystal, MD, Chair of the Department of Psychiatry at Yale University.
“Major depression is one of the most prevalent and costly illnesses in the world, and yet currently available treatments fall far short of alleviating this burden,” said Dr. Charney. “There is an urgent need for new, fast-acting therapies, and ketamine shows important potential in filling that void.”
Dr. Murrough will present his research on Sunday, May 19, 2013 from 1:00 pm to 3:00 pm in the Moscone exhibit hall at the APA meeting.
Whether we’re listening to Bach or the blues, our brains are wired to make music-color connections depending on how the melodies make us feel, according to new research from the University of California, Berkeley. For instance, Mozart’s jaunty Flute Concerto No. 1 in G major is most often associated with bright yellow and orange, whereas his dour Requiem in D minor is more likely to be linked to dark, bluish gray.
Moreover, people in both the United States and Mexico linked the same pieces of classical orchestral music with the same colors. This suggests that humans share a common emotional palette – when it comes to music and color – that appears to be intuitive and can cross cultural barriers, UC Berkeley researchers said.
“The results were remarkably strong and consistent across individuals and cultures and clearly pointed to the powerful role that emotions play in how the human brain maps from hearing music to seeing colors,” said UC Berkeley vision scientist Stephen Palmer, lead author of a paper published this week in the journal Proceedings of the National Academy of Sciences.
Using a 37-color palette, the UC Berkeley study found that people tend to pair faster-paced music in a major key with lighter, more vivid, yellow colors, whereas slower-paced music in a minor key is more likely to be teamed up with darker, grayer, bluer colors.
“Surprisingly, we can predict with 95 percent accuracy how happy or sad the colors people pick will be based on how happy or sad the music is that they are listening to,” said Palmer, who will present these and related findings at the International Association of Colour conference at the University of Newcastle in the U.K. on July 8. At the conference, a color light show will accompany a performance by the Northern Sinfonia orchestra to demonstrate “the patterns aroused by music and color converging on the neural circuits that register emotion,” he said.
The findings may have implications for creative therapies, advertising and even music player gadgetry. For example, they could be used to create more emotionally engaging electronic music visualizers, computer software that generates animated imagery synchronized to the music being played. Right now, the colors and patterns appear to be randomly generated and do not take emotion into account, researchers said.
They may also provide insight into synesthesia, a neurological condition in which the stimulation of one perceptual pathway, such as hearing music, leads to automatic, involuntary experiences in a different perceptual pathway, such as seeing colors. An example of sound-to-color synesthesia was portrayed in the 2009 movie The Soloist when cellist Nathaniel Ayers experiences a mesmerizing interplay of swirling colors while listening to the Los Angeles symphony. Artists such as Wassily Kandinksky and Paul Klee may have used music-to-color synesthesia in their creative endeavors.
Nearly 100 men and women participated in the UC Berkeley music-color study, of which half resided in the San Francisco Bay Area and the other half in Guadalajara, Mexico. In three experiments, they listened to 18 classical music pieces by composers Johann Sebastian Bach, Wolfgang Amadeus Mozart and Johannes Brahms that varied in tempo (slow, medium, fast) and in major versus minor keys.
In the first experiment, participants were asked to pick five of the 37 colors that best matched the music to which they were listening. The palette consisted of vivid, light, medium, and dark shades of red, orange, yellow, green, yellow-green, green, blue-green, blue, and purple.
Participants consistently picked bright, vivid, warm colors to go with upbeat music and dark, dull, cool colors to match the more tearful or somber pieces. Separately, they rated each piece of music on a scale of happy to sad, strong to weak, lively to dreary and angry to calm.
Two subsequent experiments studying music-to-face and face-to-color associations supported the researchers’ hypothesis that “common emotions are responsible for music-to-color associations,” said Karen Schloss, a postdoctoral researchers at UC Berkeley and co-author of the paper.
For example, the same pattern occurred when participants chose the facial expressions that “went best” with the music selections, Schloss said. Upbeat music in major keys was consistently paired with happy-looking faces while subdued music in minor keys was paired with sad-looking faces. Similarly, happy faces were paired with yellow and other bright colors and angry faces with dark red hues.
Next, Palmer and his research team plan to study participants in Turkey where traditional music employs a wider range of scales than just major and minor. “We know that in Mexico and the U.S. the responses are very similar,” he said. “But we don’t yet know about China or Turkey.”
Our researchers have found a previously undiscovered link between epileptic seizures and the signs of autism in adults.
Dr SallyAnn Wakeford from the Department of Psychology revealed that adults with epilepsy were more likely to have higher traits of autism and Asperger syndrome.
Characteristics of autism, which include impairment in social interaction and communication as well as restricted and repetitive interests, can be severe and go unnoticed for many years, having tremendous impact on the lives of those who have them.
The research found that epileptic seizures disrupt the neurological function that affects social functioning in the brain resulting in the same traits seen in autism.
Dr Wakeford said: “The social difficulties in epilepsy have been so far under-diagnosed and research has not uncovered any underlying theory to explain them. This new research links social difficulties to a deficit in somatic markers in the brain, explaining these characteristics in adults with epilepsy.”
Dr Wakeford and her colleagues discovered that having increased autistic traits was common to all epilepsy types, however, this was more pronounced for adults with Temporal Lobe Epilepsy (TLE).
The researchers suggest that one explanation may be because anti-epileptic drugs are often less effective for TLE. The reason why they suspect these drugs are implicated is because they were strongly related to the severity of autistic characteristics.
Dr Wakeford carried out a comprehensive range of studies with volunteers with epilepsy and discovered that all of the adults with epilepsy showed autism traits.
She said: “It is unknown whether these adults had a typical developmental period during childhood or whether they were predisposed to having autistic traits before the onset of their epilepsy. However what is known is that the social components of autistic characteristics in adults with epilepsy may be explained by social cognitive differences, which have largely been unrecognised until now.”
Dr Wakeford said the findings could lead to improved treatment for people with epilepsy and autism. She said: “Epilepsy has a history of cultural stigma, however the more we understand about the psychological consequences of epilepsy the more we can remove the stigma and mystique of this condition.
“These findings could mean that adults with epilepsy get access to better services, as there is a wider range of treatments available for those with autism condition.”
Margaret Rawnsley, research administration officer at Epilepsy Action welcomed the findings.
She said: “We welcome any research that could further our understanding of epilepsy and ultimately improve the lives of those with the condition. This research has the potential to tell us more about the links between epilepsy and other conditions, such as autism spectrum disorders.”
The song, “Get Happy,” famously performed by Judy Garland, has encouraged people to improve their mood for decades. Recent research at the University of Missouri discovered that an individual can indeed successfully try to be happier, especially when cheery music aids the process. This research points to ways that people can actively improve their moods and corroborates earlier MU research.
“Our work provides support for what many people already do – listen to music to improve their moods,” said lead author Yuna Ferguson, who performed the study while she was an MU doctoral student in psychological science. “Although pursuing personal happiness may be thought of as a self-centered venture, research suggests that happiness relates to a higher probability of socially beneficial behavior, better physical health, higher income and greater relationship satisfaction.”
In two studies by Ferguson, participants successfully improved their moods in the short term and boosted their overall happiness over a two week period. During the first study, participants improved their mood after being instructed to attempt to do so, but only if they listened to the upbeat music of Copland, as opposed to the more somber Stravinsky. Other participants, who simply listened to the music without attempting to change their mood, also didn’t report a change in happiness. In the second study, participants reported higher levels of happiness after two weeks of lab sessions in which they listened to positive music while trying to feel happier, compared to control participants who only listened to music.
However, Ferguson noted that for people to put her research into practice, they must be wary of too much introspection into their mood or constantly asking, “Am I happy yet?”
“Rather than focusing on how much happiness they’ve gained and engaging in that kind of mental calculation, people could focus more on enjoying their experience of the journey towards happiness and not get hung up on the destination,” said Ferguson.
Ferguson’s work corroborated earlier findings by Ferguson’s doctoral advisor and co-author of the current study, Kennon Sheldon, professor of psychological science in MU’s College of Arts and Science.
“The Hedonic Adaptation Prevention model, developed in my earlier research, says that we can stay in the upper half of our ‘set range’ of potential happiness as long as we keep having positive experiences, and avoid wanting too much more than we have,” said Sheldon. “Yuna’s research suggests that we can intentionally seek to make mental changes leading to new positive experiences of life. The fact that we’re aware we’re doing this, has no detrimental effect.”
Ferguson is now assistant professor of psychology at Pennsylvania State University Shenango. The study, “Trying to Be Happier Really Can Work: Two Experimental Studies,” was published in The Journal of Positive Psychology.
New research from Wake Forest Baptist Medical Center finds that suicide, while strongly associated with psychiatric conditions, also correlates with environmental pollution.
Lead researcher John G. Spangler, M.D., M.P.H., a professor of family medicine at Wake Forest Baptist, looked specifically at the relationship between air pollution and emissions from coal-fired electricity plants.
“This study raises interesting questions about suicide rates in counties where coal-fired electrical plants operate and suggests that the quality of air can affect people suffering from different mood disorders,” Spangler said.
For this ecological study, Spangler evaluated air level contaminates in 20 North Carolina counties where coal-fired electricity plants existed, using data from the 2000 U.S. Census, 2001-2005 mortality rates from the N.C. State Center for Health Statistics and the U.S. Environmental Protection Agency.
County-level suicide rates were higher overall in North Carolina (12.4 per 100,000 population) compared to the U.S. population (10.8 per 100,000). The study found that for each additional coal-fired electricity plant per N.C. county, there were about two additional suicides per 100,000 population annually per county. As there were 20 coal-fired electricity plants in North Carolina when this study was carried out, that means there were about 40 suicides a year per 100,000 population related to the plants. When applied to the state’s year 2,000 population of 8,049,313, this equals about 3,220 suicides a year associated with coal-fired electricity plants.
The study is published in the most recent online edition of the Journal of Mood Disorders.
“The presence of a coal-fired electricity plant correlated with airborne levels of nickel, mercury, lead, chromium, cadmium, beryllium and arsenic,” Spangler said.
While prior research has evaluated the association between environmental contamination and mood disorders and suicide, coal emissions have not been looked at in this fashion, Spangler said. “This is the first study to show that the existence of coal-fired electricity plants is related to population-level suicide rates. Because suicide might be associated with environmental pollution, this study may help inform regulations not only of air pollutants, but also of coal-fired electrical power plant emissions.”
Spangler has conducted previous ecological research into environmental heavy metals, looking at their correlation to diabetes mortality, chronic liver disease death, cancer mortality and infant mortality. Spangler said the study was subject to a number of limitations because it only looked at county-level characteristics and could not control for factors in individual residents.
“Still, it raises the interesting question of whether suicide in a given population is related to the presence or absence of coal-fired electricity plants and the air quality,” he said. “Further research is needed to understand what factors related to coal burning actually are at play and suggest that tighter regulation of coal-fired power plant emissions might cut down on county suicide rates in North Carolina.”
(Image: David Freund)
Your brain often works on autopilot when it comes to grammar. That theory has been around for years, but University of Oregon neuroscientists have captured elusive hard evidence that people indeed detect and process grammatical errors with no awareness of doing so.
Participants in the study — native-English speaking people, ages 18-30 — had their brain activity recorded using electroencephalography, from which researchers focused on a signal known as the Event-Related Potential (ERP). This non-invasive technique allows for the capture of changes in brain electrical activity during an event. In this case, events were short sentences presented visually one word at a time.
Subjects were given 280 experimental sentences, including some that were syntactically (grammatically) correct and others containing grammatical errors, such as “We drank Lisa’s brandy by the fire in the lobby,” or “We drank Lisa’s by brandy the fire in the lobby.” A 50 millisecond audio tone was also played at some point in each sentence. A tone appeared before or after a grammatical faux pas was presented. The auditory distraction also appeared in grammatically correct sentences.
This approach, said lead author Laura Batterink, a postdoctoral researcher, provided a signature of whether awareness was at work during processing of the errors. “Participants had to respond to the tone as quickly as they could, indicating if its pitch was low, medium or high,” she said. “The grammatical violations were fully visible to participants, but because they had to complete this extra task, they were often not consciously aware of the violations. They would read the sentence and have to indicate if it was correct or incorrect. If the tone was played immediately before the grammatical violation, they were more likely to say the sentence was correct even it wasn’t.”
When tones appeared after grammatical errors, subjects detected 89 percent of the errors. In cases where subjects correctly declared errors in sentences, the researchers found a P600 effect, an ERP response in which the error is recognized and corrected on the fly to make sense of the sentence.
When the tones appear before the grammatical errors, subjects detected only 51 percent of them. The tone before the event, said co-author Helen J. Neville, who holds the UO’s Robert and Beverly Lewis Endowed Chair in psychology, created a blink in their attention. The key to conscious awareness, she said, is based on whether or not a person can declare an error, and the tones disrupted participants’ ability to declare the errors. But, even when the participants did not notice these errors, their brains responded to them, generating an early negative ERP response. These undetected errors also delayed participants’ reaction times to the tones.
“Even when you don’t pick up on a syntactic error your brain is still picking up on it,” Batterink said. “There is a brain mechanism recognizing it and reacting to it, processing it unconsciously so you understand it properly.”
The study was published in the May 8 issue of the Journal of Neuroscience.
The brain processes syntactic information implicitly, in the absence of awareness, the authors concluded. “While other aspects of language, such as semantics and phonology, can also be processed implicitly, the present data represent the first direct evidence that implicit mechanisms also play a role in the processing of syntax, the core computational component of language.”
It may be time to reconsider some teaching strategies, especially how adults are taught a second language, said Neville, a member of the UO’s Institute of Neuroscience and director of the UO’s Brain Development Lab.
Children, she noted, often pick up grammar rules implicitly through routine daily interactions with parents or peers, simply hearing and processing new words and their usage before any formal instruction. She likened such learning to “Jabberwocky,” the nonsense poem introduced by writer Lewis Carroll in 1871 in “Through the Looking Glass,” where Alice discovers a book in an unrecognizable language that turns out to be written inversely and readable in a mirror.
For a second language, she said, “Teach grammatical rules implicitly, without any semantics at all, like with jabberwocky. Get them to listen to jabberwocky, like a child does.”