Posts tagged individual differences
Articles and news from the latest research reports.
Presence or absence of early language delay alters anatomy of the brain in autism
A new study led by researchers from the University of Cambridge has found that a common characteristic of autism – language delay in early childhood – leaves a ‘signature’ in the brain. The results are published today (23 September) in the journal Cerebral Cortex.
The researchers studied 80 adult men with autism: 38 who had delayed language onset and 42 who did not. They found that language delay was associated with differences in brain volume in a number of key regions, including the temporal lobe, insula, ventral basal ganglia, which were all smaller in those with language delay; and in brainstem structures, which were larger in those with delayed language onset.
Additionally, they found that current language function is associated with a specific pattern of grey and white matter volume changes in some key brain regions, particularly temporal, frontal and cerebellar structures.
The Cambridge researchers, in collaboration with King’s College London and the University of Oxford, studied participants who were part of the MRC Autism Imaging Multicentre Study (AIMS).
Delayed language onset – defined as when a child’s first meaningful words occur after 24 months of age, or their first phrase occurs after 33 months of age – is seen in a subgroup of children with autism, and is one of the clearest features triggering an assessment for developmental delay in children, including an assessment of autism.
“Although people with autism share many features, they also have a number of key differences,” said Dr Meng-Chuan Lai of the Cambridge Autism Research Centre, and the paper’s lead author. “Language development and ability is one major source of variation within autism. This new study will help us understand the substantial variety within the umbrella category of ‘autism spectrum’. We need to move beyond investigating average differences in individuals with and without autism, and move towards identifying key dimensions of individual differences within the spectrum.”
He added: “This study shows how the brain in men with autism varies based on their early language development and their current language functioning. This suggests there are potentially long-lasting effects of delayed language onset on the brain in autism.”
Last year, the American Psychiatric Association removed Asperger Syndrome (Asperger’s Disorder) as a separate diagnosis from its diagnostic manual (DSM-5), and instead subsumed it within ‘autism spectrum disorder.’ The change was one of many controversial decisions in DSM-5, the main manual for diagnosing psychiatric conditions.
“This new study shows that a key feature of Asperger Syndrome, the absence of language delay, leaves a long lasting neurobiological signature in the brain,” said Professor Simon Baron-Cohen, senior author of the study. “Although we support the view that autism lies on a spectrum, subgroups based on developmental characteristics, such as Asperger Syndrome, warrant further study.”
“It is important to note that we found both differences and shared features in individuals with autism who had or had not experienced language delay,” said Dr Lai. “When asking: ‘Is autism a single spectrum or are there discrete subgroups?’ - the answer may be both.”
Neural reward response may demonstrate why quitting smoking is harder for some
For some cigarette smokers, strategies to aid quitting work well, while for many others no method seems to work. Researchers have now identified an aspect of brain activity that helps to predict the effectiveness of a reward-based strategy as motivation to quit smoking.
The researchers observed the brains of nicotine-deprived smokers with functional magnetic resonance imaging (fMRI) and found that those who exhibited the weakest response to rewards were also the least willing to refrain from smoking, even when offered money to do so.
"We believe that our findings may help to explain why some smokers find it so difficult to quit smoking," said Stephen J. Wilson, assistant professor of psychology, Penn State. "Namely, potential sources of reinforcement for giving up smoking — for example, the prospect of saving money or improving health — may hold less value for some individuals and, accordingly, have less impact on their behavior."
The researchers recruited 44 smokers to examine striatal response to monetary reward in those expecting to smoke and in those who were not, and the subsequent willingness of the smokers to forego a cigarette in an effort to earn more money.
"The striatum is part of the so-called reward system in the brain," said Wilson. "It is the area of the brain that is important for motivation and goal-directed behavior — functions highly relevant to addiction."
The participants, who were between the ages of 18 and 45, all reported that they smoked at least 10 cigarettes per day for the past 12 months. They were instructed to abstain from smoking and from using any products containing nicotine for 12 hours prior to arriving for the experiment.
Each participant spent time in an fMRI scanner while playing a card-guessing game with the potential to win money. The participants were informed that they would have to wait approximately two hours, until the experiment was over, to smoke a cigarette. Partway through the card-guessing task, half of the participants were informed that there had been a mistake, and they would be allowed to smoke during a 50-minute break that would occur in another 16 minutes.
However, when the time came for the cigarette break, the participant was told that for every 5 minutes he or she did not smoke, he or she would receive $1 — with the potential to earn up to $10.
Wilson and his colleagues reported in a recent issue of Cognitive, Affective and Behavioral Neuroscience that they found that smokers who could not resist the temptation to smoke also showed weaker responses in the ventral striatum when offered monetary rewards while in the fMRI.
"Our results suggest that it may be possible to identify individuals prospectively by measuring how their brains respond to rewards, an observation that has significant conceptual and clinical implications," said Wilson. "For example, particularly ‘at-risk’ smokers could potentially be identified prior to a quit attempt and be provided with special interventions designed to increase their chances for success."
Exploring the Genetics of “I’ll Do It Tomorrow”
Procrastination and impulsivity are genetically linked, suggesting that the two traits stem from similar evolutionary origins, according to research published in Psychological Science, a journal of the Association for Psychological Science. The research indicates that the traits are related to our ability to successfully pursue and juggle goals.
“Everyone procrastinates at least sometimes, but we wanted to explore why some people procrastinate more than others and why procrastinators seem more likely to make rash actions and act without thinking,” explains psychological scientist and study author Daniel Gustavson of the University of Colorado Boulder. “Answering why that’s the case would give us some interesting insights into what procrastination is, why it occurs, and how to minimize it.”
From an evolutionary standpoint, impulsivity makes sense: Our ancestors should have been inclined to seek immediate rewards when the next day was uncertain.
Procrastination, on the other hand, may have emerged more recently in human history. In the modern world, we have many distinct goals far in the future that we need to prepare for – when we’re impulsive and easily distracted from those long-term goals, we often procrastinate.
Thinking about the two traits in that context, it seems logical that people who are perpetual procrastinators would also be highly impulsive. Many studies have observed this positive relationship, but it is unclear what cognitive, biological, and environmental influences are responsible for it.
The most effective way to understand why these traits are correlated is to study human twins. Identical twins — who share 100% of their genes — tend to show greater similarities in behavior than fraternal twins, who only share 50% of their genes (just like any other siblings). Researchers take advantage of this genetic discrepancy to figure out the relative importance of genetic and environmental influences on particular behaviors, like procrastination and impulsivity.
Gustavson and colleagues had 181 identical-twin pairs and 166 fraternal-twin pairs complete several surveys intended to probe their tendencies toward impulsivity and procrastination, as well as their ability to set and maintain goals.
They found that procrastination is indeed heritable, just like impulsivity. Not only that, there seems to be a complete genetic overlap between procrastination and impulsivity — that is, there are no genetic influences that are unique to either trait alone.
That finding suggests that, genetically speaking, procrastination is an evolutionary byproduct of impulsivity — one that likely manifests itself more in the modern world than in the world of our ancestors.
In addition, the link between procrastination and impulsivity also overlapped genetically with the ability to manage goals, lending support to the idea that delaying, making rash decisions, and failing to achieve goals all stem from a shared genetic foundation.
Gustavson and colleagues are now investigating how procrastination and impulsivity are related to higher-level cognitive abilities, such as executive functions, and whether these same genetic influences are related to other aspects of self-regulation in our day-to-day lives.
“Learning more about the underpinnings of procrastination may help develop interventions to prevent it, and help us overcome our ingrained tendencies to get distracted and lose track of work,” Gustavson concludes.
Gender and genes play an important role in delayed language development
Boys are at greater risk for delayed language development than girls, according to a new study using data from the Norwegian Mother and Child Cohort Study. The researchers also found that reading and writing difficulties in the family gave an increased risk.
“We show for the first time that reading and writing difficulties in the family can be the main reason why a child has a speech delay that first begins between three to five years of age,” says Eivind Ystrøm, senior researcher at the Norwegian Institute of Public Health.
Ystrøm was supervisor of Imac Maria Zambrana, a former PhD student at the Norwegian Institute of Public Health who conducted the research in this study as part of her doctoral research.
The researchers used data from questionnaires completed by the mothers who are participating in the Norwegian Mother and Child Cohort Study (MoBa). The study included more than 10,000 children from week 17 of pregnancy up to five years of age.
“MoBa is a large study with a normal cross-section of the population. It gives us a unique opportunity to examine changes over time, the scope and any risk factors for delayed language development,” says Ystrøm.
Mostly boys
The researchers classified the language difficulties at three and five years of age in three groups: persistent delayed language development (present at both times), transient delayed language development (only present at three years) and delayed language development first identified at five years old.
Boys are in the majority for the groups with persistent and transient language difficulties. Ystrøm explains that boys are biologically at greater risk for developmental disorders in utero than girls. British scientists have measured the male sex hormone (testosterone) in amniotic fluid and they found that the levels were related to the development of both autism and language disorders. Ystrøm points out that boys are generally a little later in language development than girls, but that most catch up during the first year. Therefore, many boys could be at risk of persistent language impairment and increasingly have transient language difficulties that disappear before school age.
The researchers found that gender was irrelevant for the third group who have language difficulties that begin sometime between three and five years of age.
Hereditary factors
We have good knowledge about normal language development in children. Many genes are important for language development and research suggests that different genes are involved in different types of language difficulty.
“Reading and writing difficulties in the family are the predominant risk factors for late-onset language difficulties. We see no language problems when the child is between 18 months and three years old. They are latent” says Ystrøm.
The researchers believe that both specific genes and factors in the child’s external environment can lead to delays in language development at three to five years of age.
What can we do?
Ystrøm believes that children with delayed language development must be identified as early as possible. Parents, health care workers and child care staff should be aware of the language development of children and encourage an enabling language environment, in some cases with specially adapted measures. In particular, they must be aware of children who have sustained disabilities, or who have had normal language development up to three years and then unexpectedly began to have difficulties.
“Professionals and caregivers must be vigilant. It is difficult to detect language difficulties when language becomes more complex in older children. They must be trained so that they are confident in how to spot language difficulties and how to encourage a child’s language. We need more research into the needs of children with different trajectories”, says Ystrøm.
Parents who are concerned about their child’s language development should consult their doctor. They should also raise the issue at the regular check-ups at the health clinic when the child is between two and four years old.
“The checks must take place at the appropriate time. It is important that they are not delayed or not implemented at all,” says Ystrøm.
A few years ago, a survey by the Health and Welfare Department in Oslo showed that few of the health centres in Oslo met the required 14 consultations for each child from birth to school stipulated by the Norwegian Directorate of Health.
Further research
In addition to researchers at the Norwegian Institute of Public Health, researchers at the University of Oslo and the University of Melbourne in Australia participated in this study. The work is funded by the Extra Foundation for Health and Rehabilitation.
“We hope to continue this research and specifically look at the relationship between gender and language. We need more research into the needs of children with various types of language delay”, says Eivind Ystrøm.
Reference
Zambrana, IM, Pons, F., Eadie, P. and Ystrom, E. (2013). Trajectories of language delay from age 3 to 5: persistence, recovery and late onset. International Journal of Language & Communication
(Source: fhi.no)
No math gene: learning mathematics takes practice
New research from the Norwegian University of Science and Technology shows that if you want to be good at math, you have to practice all different kinds of maths.
What makes someone good at math? A love of numbers, perhaps, but a willingness to practice, too. And even if you are good at one specific type of math, you can’t trust your innate abilities enough to skip practicing other types if you want to be good.
New research at the Norwegian University of Science and Technology (NTNU) in Trondheim could have an effect on how math is taught. If you want to be really good at all types of math, you need to practice them all. You can’t trust your innate natural talent to do most of the job for you.
This might seem obvious to some, but it goes against the traditional view that if you are good at math, it is a skill that you are simply born with.
Professor Hermundur Sigmundsson at Department of Psychology is one of three researchers involved in the project. The results have been published in Psychological Reports.
The numbers
The researchers tested the math skills of 70 Norwegian fifth graders, aged 10.5 years on average. Their results suggest that it is important to practice every single kind of math subject to be good at all of them, and that these skills aren’t something you are born with.
“We found support for a task specificity hypothesis. You become good at exactly what you practice,” Sigmundsson says.
Nine types of math tasks were tested, from normal addition and subtraction, both orally and in writing, to oral multiplication and understanding the clock and the calendar.
“Our study shows little correlation between (being good at) the nine different mathematical skills, Sigmundsson said. “For instance there is little correlation between being able to solve a normal addition in the form of ‘23 + 67’ and addition in the form of a word problem.”
This example might raise a few eyebrows. Perhaps basic math is not a problem for the student, but the reading itself is. Up to 20 per cent of Norwegian boys in secondary school have problems with reading.
Sigmundsson also finds support in everyday examples.
“Some students will be good at geometry, but not so good at algebra,” he says.
If that is the case they have to practice more algebra, which is the area where most students in secondary school have problems.
“At the same time this means there is hope for some students. Some just can’t be good at all types of math, but at least they can be good at geometry, for example,” he says.
It is this finding that might in the end help change the way math is taught.
Support in neurology
The fact that you are good at precisely what you practice is probably due to the fact that different kinds of practice activate different neural connections.
The results can also be transferred to other areas. The football player who practices hitting the goal from 25 yards with a perfectly placed shot will become good at exactly this. But she is not necessarily good at tackling or reading the game.
“This is also supported by new insights in neurology. With practice you develop specific neural connections,” says Sigmundsson.
(Source: alphagalileo.org)
Picking Up a Second Language Is Predicted by Ability to Learn Patterns
Some people seem to pick up a second language with relative ease, while others have a much more difficult time. Now, a new study suggests that learning to understand and read a second language may be driven, at least in part, by our ability to pick up on statistical regularities.
The study is published in Psychological Science, a journal of the Association for Psychological Science.
Some research suggests that learning a second language draws on capacities that are language-specific, while other research suggests that it reflects a more general capacity for learning patterns. According to psychological scientist and lead researcher Ram Frost of Hebrew University, the data from the new study clearly point to the latter:
“These new results suggest that learning a second language is determined to a large extent by an individual ability that is not at all linguistic,” says Frost.
In the study, Frost and colleagues used three different tasks to measure how well American students in an overseas program picked up on the structure of words and sounds in Hebrew. The students were tested once in the first semester and again in the second semester.
The students also completed a task that measured their ability to pick up on statistical patterns in visual stimuli. The participants watched a stream of complex shapes that were presented one at a time. Unbeknownst to the participants, the 24 shapes were organized into 8 triplets — the order of the triplets was randomized, though the shapes within each triplet always appeared in the same sequence. After viewing the stream of shapes, the students were tested to see whether they implicitly picked up the statistical regularities of the shape sequences.
The data revealed a strong association between statistical learning and language learning: Students who were high performers on the shapes task tended to pick up the most Hebrew over the two semesters.
“It’s surprising that a short 15-minute test involving the perception of visual shapes could predict to such a large extent which of the students who came to study Hebrew would finish the year with a better grasp of the language,” says Frost.
According to the researchers, establishing a link between second language acquisition and a general capacity for statistical learning may have broad implications.
“This finding points to the possibility that a unified and universal principle of statistical learning can quantitatively explain a wide range of cognitive processes across domains, whether they are linguistic or nonlinguistic,” they conclude.