Neuroscience

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Posts tagged cognitive function

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Children’s drawings indicate later intelligence
How 4-year old children draw pictures of a child is an indicator of intelligence at age 14, according to a study by the Institute of Psychiatry at King’s College London, published today in Psychological Science.
The researchers studied 7,752 pairs of identical and non-identical twins (a total of 15,504 children) from the Medical Research Council (MRC) funded Twins Early Development Study (TEDS), and found that the link between drawing and later intelligence was influenced by genes.
At the age of 4, children were asked by their parents to complete a ‘Draw-a-Child’ test, i.e. draw a picture of a child. Each figure was scored between 0 and 12 depending on the presence and correct quantity of features such as head, eyes, nose, mouth, ears, hair, body, arms etc. For example, a drawing with two legs, two arms, a body and head, but no facial features, would score 4. The children were also given verbal and non-verbal intelligence tests at ages 4 and 14.
The researchers found that higher scores on the Draw-a-Child test were moderately associated with higher scores of intelligence at ages 4 and 14. The correlation between drawing and intelligence was moderate at ages 4 (0.33) and 14 (0.20).
Dr Rosalind Arden, lead author of the paper from the MRC Social, Genetic and Developmental Psychiatry (SGDP) Centre at the Institute of Psychiatry at King’s College London, says: “The Draw-a-Child test was devised in the 1920’s to assess children’s intelligence, so the fact that the test correlated with intelligence at age 4 was expected.What surprised us was that it correlated with intelligence a decade later.”
“The correlation is moderate, so our findings are interesting, but it does not mean that parents should worry if their child draws badly. Drawing ability does not determine intelligence, there are countless factors, both genetic and environmental, which affect intelligence in later life.”
The researchers also measured the heritability of figure drawing. Identical twins share all their genes, whereas non-identical twins only share about 50 percent, but each pair will have a similar upbringing, family environment and access to the same materials.
Overall, at age 4, drawings from identical twins pairs were more similar to one another than drawings from non-identical twin pairs. Therefore, the researchers concluded that differences in children’s drawings have an important genetic link. They also found that drawing at age 4 and intelligence at age 14 had a strong genetic link.
Dr Arden explains: “This does not mean that there is a drawing gene – a child’s ability to draw stems from many other abilities, such as observing, holding a pencil etc. We are a long way off understanding how genes influence all these different types of behaviour.”
Dr Arden adds: “Drawing is an ancient behaviour, dating back beyond 15,000 years ago. Through drawing, we are attempting to show someone else what’s in our mind. This capacity to reproduce figures is a uniquely human ability and a sign of cognitive ability, in a similar way to writing, which transformed the human species’ ability to store information, and build a civilisation.”

Children’s drawings indicate later intelligence

How 4-year old children draw pictures of a child is an indicator of intelligence at age 14, according to a study by the Institute of Psychiatry at King’s College London, published today in Psychological Science.

The researchers studied 7,752 pairs of identical and non-identical twins (a total of 15,504 children) from the Medical Research Council (MRC) funded Twins Early Development Study (TEDS), and found that the link between drawing and later intelligence was influenced by genes.

At the age of 4, children were asked by their parents to complete a ‘Draw-a-Child’ test, i.e. draw a picture of a child. Each figure was scored between 0 and 12 depending on the presence and correct quantity of features such as head, eyes, nose, mouth, ears, hair, body, arms etc. For example, a drawing with two legs, two arms, a body and head, but no facial features, would score 4. The children were also given verbal and non-verbal intelligence tests at ages 4 and 14.

The researchers found that higher scores on the Draw-a-Child test were moderately associated with higher scores of intelligence at ages 4 and 14. The correlation between drawing and intelligence was moderate at ages 4 (0.33) and 14 (0.20).

Dr Rosalind Arden, lead author of the paper from the MRC Social, Genetic and Developmental Psychiatry (SGDP) Centre at the Institute of Psychiatry at King’s College London, says: “The Draw-a-Child test was devised in the 1920’s to assess children’s intelligence, so the fact that the test correlated with intelligence at age 4 was expected.What surprised us was that it correlated with intelligence a decade later.”

“The correlation is moderate, so our findings are interesting, but it does not mean that parents should worry if their child draws badly. Drawing ability does not determine intelligence, there are countless factors, both genetic and environmental, which affect intelligence in later life.”

The researchers also measured the heritability of figure drawing. Identical twins share all their genes, whereas non-identical twins only share about 50 percent, but each pair will have a similar upbringing, family environment and access to the same materials.

Overall, at age 4, drawings from identical twins pairs were more similar to one another than drawings from non-identical twin pairs. Therefore, the researchers concluded that differences in children’s drawings have an important genetic link. They also found that drawing at age 4 and intelligence at age 14 had a strong genetic link.

Dr Arden explains: “This does not mean that there is a drawing gene – a child’s ability to draw stems from many other abilities, such as observing, holding a pencil etc. We are a long way off understanding how genes influence all these different types of behaviour.”

Dr Arden adds: “Drawing is an ancient behaviour, dating back beyond 15,000 years ago. Through drawing, we are attempting to show someone else what’s in our mind. This capacity to reproduce figures is a uniquely human ability and a sign of cognitive ability, in a similar way to writing, which transformed the human species’ ability to store information, and build a civilisation.”

Filed under intelligence child development drawing genes cognitive function psychology neuroscience science

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Physically fit kids have beefier brain white matter than their less-fit peers
A new study of 9- and 10-year-olds finds that those who are more aerobically fit have more fibrous and compact white-matter tracts in the brain than their peers who are less fit. “White matter” describes the bundles of axons that carry nerve signals from one brain region to another. More compact white matter is associated with faster and more efficient nerve activity.
The team reports its findings in the open-access journal Frontiers in Human Neuroscience.
“Previous studies suggest that children with higher levels of aerobic fitness show greater brain volumes in gray-matter brain regions important for memory and learning,” said University of Illinois postdoctoral researcher Laura Chaddock-Heyman, who conducted the study with kinesiology and community health professor Charles Hillman and psychology professor and Beckman Institute director Arthur Kramer. “Now for the first time we explored how aerobic fitness relates to white matter in children’s brains.”
The team used diffusion tensor imaging (DTI, also called diffusion MRI) to look at five white-matter tracts in the brains of the 24 participants. This method analyzes water diffusion into tissues. For white matter, less water diffusion means the tissue is more fibrous and compact, both desirable traits.
The researchers controlled for several variables – such as social and economic status, the timing of puberty, IQ, or a diagnosis of ADHD or other learning disabilities – that might have contributed to the reported fitness differences in the brain.
The analysis revealed significant fitness-related differences in the integrity of several white-matter tracts in the brain: the corpus callosum, which connects the brain’s left and right hemispheres; the superior longitudinal fasciculus, a pair of structures that connect the frontal and parietal lobes; and the superior corona radiata, which connect the cerebral cortex to the brain stem.  “All of these tracts have been found to play a role in attention and memory,” Chaddock-Heyman said.
The team did not test for cognitive differences in the children in this study, but previous work has demonstrated a link between improved aerobic fitness and gains in cognitive function on specific tasks and in academic settings.
“Previous studies in our lab have reported a relationship between fitness and white-matter integrity in older adults,” Kramer said. “Therefore, it appears that fitness may have beneficial effects on white matter throughout the lifespan.”
To take the findings further, the team is now two years into a five-year randomized, controlled trial to determine whether white-matter tract integrity improves in children who begin a new physical fitness routine and maintain it over time. The researchers are looking for changes in aerobic fitness, brain structure and function, and genetic regulation.
“Prior work from our laboratories has demonstrated both short- and long-term differences in the relation of aerobic fitness to brain health and cognition,” Hillman said. “However, our current randomized, controlled trial should provide the most comprehensive assessment of this relationship to date.”
The new findings add to the evidence that aerobic exercise changes the brain in ways that improve cognitive function, Chaddock-Heyman said.
“This study extends our previous work and suggests that white-matter structure may be one additional mechanism by which higher-fit children outperform their lower-fit peers on cognitive tasks and in the classroom,” she said.

Physically fit kids have beefier brain white matter than their less-fit peers

A new study of 9- and 10-year-olds finds that those who are more aerobically fit have more fibrous and compact white-matter tracts in the brain than their peers who are less fit. “White matter” describes the bundles of axons that carry nerve signals from one brain region to another. More compact white matter is associated with faster and more efficient nerve activity.

The team reports its findings in the open-access journal Frontiers in Human Neuroscience.

“Previous studies suggest that children with higher levels of aerobic fitness show greater brain volumes in gray-matter brain regions important for memory and learning,” said University of Illinois postdoctoral researcher Laura Chaddock-Heyman, who conducted the study with kinesiology and community health professor Charles Hillman and psychology professor and Beckman Institute director Arthur Kramer. “Now for the first time we explored how aerobic fitness relates to white matter in children’s brains.”

The team used diffusion tensor imaging (DTI, also called diffusion MRI) to look at five white-matter tracts in the brains of the 24 participants. This method analyzes water diffusion into tissues. For white matter, less water diffusion means the tissue is more fibrous and compact, both desirable traits.

The researchers controlled for several variables – such as social and economic status, the timing of puberty, IQ, or a diagnosis of ADHD or other learning disabilities – that might have contributed to the reported fitness differences in the brain.

The analysis revealed significant fitness-related differences in the integrity of several white-matter tracts in the brain: the corpus callosum, which connects the brain’s left and right hemispheres; the superior longitudinal fasciculus, a pair of structures that connect the frontal and parietal lobes; and the superior corona radiata, which connect the cerebral cortex to the brain stem.
“All of these tracts have been found to play a role in attention and memory,” Chaddock-Heyman said.

The team did not test for cognitive differences in the children in this study, but previous work has demonstrated a link between improved aerobic fitness and gains in cognitive function on specific tasks and in academic settings.

“Previous studies in our lab have reported a relationship between fitness and white-matter integrity in older adults,” Kramer said. “Therefore, it appears that fitness may have beneficial effects on white matter throughout the lifespan.”

To take the findings further, the team is now two years into a five-year randomized, controlled trial to determine whether white-matter tract integrity improves in children who begin a new physical fitness routine and maintain it over time. The researchers are looking for changes in aerobic fitness, brain structure and function, and genetic regulation.

“Prior work from our laboratories has demonstrated both short- and long-term differences in the relation of aerobic fitness to brain health and cognition,” Hillman said. “However, our current randomized, controlled trial should provide the most comprehensive assessment of this relationship to date.”

The new findings add to the evidence that aerobic exercise changes the brain in ways that improve cognitive function, Chaddock-Heyman said.

“This study extends our previous work and suggests that white-matter structure may be one additional mechanism by which higher-fit children outperform their lower-fit peers on cognitive tasks and in the classroom,” she said.

Filed under white matter diffusion tensor imaging aerobic fitness cognitive function memory neuroscience science

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In search for Alzheimer’s drug, a major STEP forward

Researchers at Yale School of Medicine have discovered a new drug compound that reverses the brain deficits of Alzheimer’s disease in an animal model. Their findings are published in the Aug. 5 issue of the journal PLoS Biology.

The compound, TC-2153, inhibits the negative effects of a protein called STtriatal-Enriched tyrosine Phosphatase (STEP), which is key to regulating learning and memory. These cognitive functions are impaired in Alzheimer’s.

"Decreasing STEP levels reversed the effects of Alzheimer’s disease in mice," said lead author Paul Lombroso, M.D., professor in the Yale Child Study Center and in the Departments of Neurobiology and Psychiatry at Yale School of Medicine.

Lombroso and co-authors studied thousands of small molecules, searching for those that would inhibit STEP activity. Once identified, those STEP-inhibiting compounds were tested in brain cells to examine how effectively they could halt the effects of STEP. They examined the most promising compound in a mouse model of Alzheimer’s disease, and found a reversal of deficits in several cognitive exercises that gauged the animals’ ability to remember previously seen objects.

High levels of STEP proteins keep synapses in the brain from strengthening. Synaptic strengthening is a process that is required for people to turn short-term memories into long-term memories. When STEP is elevated in the brain, it depletes receptors from synaptic sites, and inactivates other proteins that are necessary for proper cognitive function. This disruption can result in Alzheimer’s disease or a number of neuropsychiatric and neurodegenerative disorders, all marked by cognitive deficits.

"The small molecule inhibitor is the result of a five-year collaborative effort to search for STEP inhibitors," said Lombroso. "A single dose of the drug results in improved cognitive function in mice. Animals treated with TC compound were indistinguishable from a control group in several cognitive tasks."

The team is currently testing the TC compound in other animals with cognitive defects, including rats and non-human primates. “These studies will determine whether the compound can improve cognitive deficits in other animal models,” said Lombroso. “Successful results will bring us a step closer to testing a drug that improves cognition in humans.”

(Source: eurekalert.org)

Filed under alzheimer's disease STEP TC-2153 cognitive function animal model neuroscience science

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Antipsychotic drugs linked to slight decrease in brain volume 
A study published today has confirmed a link between antipsychotic medication and a slight, but measureable, decrease in brain volume in patients with schizophrenia. For the first time, researchers have been able to examine whether this decrease is harmful for patients’ cognitive function and symptoms, and noted that over a nine year follow-up, this decrease did not appear to have any effect.
As we age, our brains naturally lose some of their volume – in other words, brain cells and connections. This process, known as atrophy, typically begins in our thirties and continues into old age. Researchers have known for some time that patients with schizophrenia lose brain volume at a faster rate than healthy individuals, though the reason why is unclear.
Now, in a study published in the open access journal PLOS ONE, a team of researchers from the University of Oulu, Finland, and the University of Cambridge has identified the rate of decrease in both healthy individuals and patients with schizophrenia. They also documented where in the brain schizophrenia patients have more atrophy, and have examined links between atrophy and antipsychotic medication.
By comparing brain scans of 33 patients with schizophrenia with 71 control subjects over a period of 9 years – from age 34 to 43 – the researchers were able to show that schizophrenia patients lost brain volume at a rate of 0.7% each year. The control participants lost brain volume at a rate of 0.5% per year.
Scientists have previously speculated that antipsychotic medication used to treat schizophrenia may be linked to this decrease in brain volume. Today’s research confirms this association, showing that the rate of decrease in volume was greater when the dose of medication was higher. However, the mechanisms behind this – and whether it was in fact the medication that was causing this greater loss of tissue – are not clear. Some researchers have previously argued that whilst older antipsychotic medications might cause brain volume decreases, newer antipsychotic medications may protect against these decreases. However, today’s research suggests that both classes of antipsychotic medication are associated with similar declines in brain volume.
The researchers also looked at whether there was any link between the volume of brain lost and the severity of symptoms or loss of cognitive function, but found no effect.
Professor Juha Veijola from the Department of Psychiatry at the University of Oulu, Finland says: “We all lose some brain tissue as we get older, but people with schizophrenia lose it at a faster rate. We’ve shown that this loss seems to be linked to the antipsychotic medication people are taking. Research like this where patients are studied for many years can help to develop guidelines about when clinicians can reduce the dosage of antipsychotic medication in the long term treatment of people with schizophrenia.”
“It’s important to stress that the loss of brain volume doesn’t appear to have any effect on people over the nine year follow-up we conducted, and patients should not stop their medication on the basis of this research,” adds Dr Graham Murray from the Behavioural and Clinical Neuroscience Institute and the Department of Psychiatry at University of Cambridge. “A key question in future will be to examine whether there is any effect of this loss of brain volume later in life. We need more research in larger studies with longer follow-ups to evaluate the significance of these brain changes.”

Antipsychotic drugs linked to slight decrease in brain volume

A study published today has confirmed a link between antipsychotic medication and a slight, but measureable, decrease in brain volume in patients with schizophrenia. For the first time, researchers have been able to examine whether this decrease is harmful for patients’ cognitive function and symptoms, and noted that over a nine year follow-up, this decrease did not appear to have any effect.

As we age, our brains naturally lose some of their volume – in other words, brain cells and connections. This process, known as atrophy, typically begins in our thirties and continues into old age. Researchers have known for some time that patients with schizophrenia lose brain volume at a faster rate than healthy individuals, though the reason why is unclear.

Now, in a study published in the open access journal PLOS ONE, a team of researchers from the University of Oulu, Finland, and the University of Cambridge has identified the rate of decrease in both healthy individuals and patients with schizophrenia. They also documented where in the brain schizophrenia patients have more atrophy, and have examined links between atrophy and antipsychotic medication.

By comparing brain scans of 33 patients with schizophrenia with 71 control subjects over a period of 9 years – from age 34 to 43 – the researchers were able to show that schizophrenia patients lost brain volume at a rate of 0.7% each year. The control participants lost brain volume at a rate of 0.5% per year.

Scientists have previously speculated that antipsychotic medication used to treat schizophrenia may be linked to this decrease in brain volume. Today’s research confirms this association, showing that the rate of decrease in volume was greater when the dose of medication was higher. However, the mechanisms behind this – and whether it was in fact the medication that was causing this greater loss of tissue – are not clear. Some researchers have previously argued that whilst older antipsychotic medications might cause brain volume decreases, newer antipsychotic medications may protect against these decreases. However, today’s research suggests that both classes of antipsychotic medication are associated with similar declines in brain volume.

The researchers also looked at whether there was any link between the volume of brain lost and the severity of symptoms or loss of cognitive function, but found no effect.

Professor Juha Veijola from the Department of Psychiatry at the University of Oulu, Finland says: “We all lose some brain tissue as we get older, but people with schizophrenia lose it at a faster rate. We’ve shown that this loss seems to be linked to the antipsychotic medication people are taking. Research like this where patients are studied for many years can help to develop guidelines about when clinicians can reduce the dosage of antipsychotic medication in the long term treatment of people with schizophrenia.”

“It’s important to stress that the loss of brain volume doesn’t appear to have any effect on people over the nine year follow-up we conducted, and patients should not stop their medication on the basis of this research,” adds Dr Graham Murray from the Behavioural and Clinical Neuroscience Institute and the Department of Psychiatry at University of Cambridge. “A key question in future will be to examine whether there is any effect of this loss of brain volume later in life. We need more research in larger studies with longer follow-ups to evaluate the significance of these brain changes.”

Filed under antipsychotics schizophrenia neuroimaging cognitive function neuroscience science

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“Noisy” Memory in Schizophrenia

The inability to ignore irrelevant stimuli underlies the impaired working memory and cognition often experienced by individuals diagnosed with schizophrenia, reports a new study in the current issue of Biological Psychiatry.

Our brains are usually good at focusing on the information that we are trying to learn and filtering out the “noise” or thoughts that aren’t relevant. However, memory impairment in schizophrenia may be related in part to a problem with this filtering process, which Dr. Teal Eich at Columbia University and her colleagues studied.

“Our assumption was that understanding the impairments in the component processes of working memory – the ability to hold and manipulate information in the mind – among patients with schizophrenia could be fundamental to understanding not only cognitive function in the disorder, which is widespread and has debilitating consequences, but also the disorder itself,” Eich explained.

The researchers recruited patients with schizophrenia and a control group of healthy volunteers to complete an item recognition task in the laboratory while undergoing a functional magnetic resonance imaging scan. In particular, they focused on analyzing potential activation differences in the ventro-lateral prefrontal cortex (VLPFC), a region of the brain implicated in working memory.

The design of the task allowed for the assessment of the various components of working memory: 1) maintaining the memory itself, 2) inhibiting or ignoring irrelevant information, and 3) during memory retrieval, controlling the interference of irrelevant information.

While simply maintaining the memory, both groups showed a similar degree of activation in the VLPFC. During the inhibition phase, VLPFC activity is expected to decrease, which was indeed observed in the healthy group, but not in the patients. Finally, during interference control, patients performed worse and showed increased VLPFC activation compared to the healthy volunteers. Overall, the patients showed altered VLPFC functioning and significant impairments in their ability to control working memory.

“Our findings show that these patients have a specific deficit in inhibiting information in working memory, leading to impaired distinctions between relevant and irrelevant thoughts,” said Eich. “This result may provide valuable insights into the potential brain mechanisms underlying the reasons why these affected individuals are unable to control or put out of mind certain thoughts or ideas.”

This study adds to a growing literature suggesting that cognitive functions require both the activation of one set of regions and the inhibition of others. The failure to suppress activation may be just as disruptive to cortical functions as deficits in cortical activation.

Many years ago, the pioneering scientist Patricia Goldman-Rakic and her colleagues showed that the inhibition of regional prefrontal cortical activity was dependent upon the integrity of the GABA (gamma-aminobutyric acid) system in the brain, a chemical system with abnormalities associated with schizophrenia.

“We need to determine whether the cortical inhibitory deficits described in this study can be attributed to particular brain chemical signaling abnormalities,” said Dr. John Krystal, Editor of Biological Psychiatry. “If so, this type of study could be used to guide therapeutic strategies to enhance working memory function.”

(Source: elsevier.com)

Filed under schizophrenia working memory prefrontal cortex neuroimaging cognitive function neuroscience science

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Speaking 2 languages benefits the aging brain

New research reveals that bilingualism has a positive effect on cognition later in life. Findings published in Annals of Neurology, a journal of the American Neurological Association and Child Neurology Society, show that individuals who speak two or more languages, even those who acquired the second language in adulthood, may slow down cognitive decline from aging.

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Bilingualism is thought to improve cognition and delay dementia in older adults. While prior research has investigated the impact of learning more than one language, ruling out “reverse causality” has proven difficult. The crucial question is whether people improve their cognitive functions through learning new languages or whether those with better baseline cognitive functions are more likely to become bilingual.

"Our study is the first to examine whether learning a second language impacts cognitive performance later in life while controlling for childhood intelligence," says lead author Dr. Thomas Bak from the Centre for Cognitive Aging and Cognitive Epidemiology at the University of Edinburgh.

For the current study, researchers relied on data from the Lothian Birth Cohort 1936, comprised of 835 native speakers of English who were born and living in the area of Edinburgh, Scotland. The participants were given an intelligence test in 1947 at age 11 years and retested in their early 70s, between 2008 and 2010. Two hundred and sixty two participants reported to be able to communicate in at least one language other than English. Of those, 195 learned the second language before age 18, 65 thereafter.

Findings indicate that those who spoke two or more languages had significantly better cognitive abilities compared to what would be expected from their baseline. The strongest effects were seen in general intelligence and reading. The effects were present in those who acquired their second language early as well as late.

The Lothian Birth Cohort 1936 forms the Disconnected Mind project at the University of Edinburgh, funded by Age UK. The work was undertaken by The University of Edinburgh Centre for Cognitive Ageing and Cognitive Epidemiology, part of the cross council Lifelong Health and Wellbeing Initiative (MR/K026992/1) and has been made possible thanks to funding from the Biotechnology and Biological Sciences Research Council (BBSRC) and Medical Research Council (MRC).

"The Lothian Birth Cohort offers a unique opportunity to study the interaction between bilingualism and cognitive aging, taking into account the cognitive abilities predating the acquisition of a second language" concludes Dr. Bak. "These findings are of considerable practical relevance. Millions of people around the world acquire their second language later in life. Our study shows that bilingualism, even when acquired in adulthood, may benefit the aging brain."

After reviewing the study, Dr. Alvaro Pascual-Leone, an Associate Editor for Annals of Neurology and Professor of Medicine at Harvard Medical School in Boston, Mass. said, “The epidemiological study by Dr. Bak and colleagues provides an important first step in understanding the impact of learning a second language and the aging brain. This research paves the way for future causal studies of bilingualism and cognitive decline prevention.”

(Source: eurekalert.org)

Filed under aging bilingualism cognition cognitive function psychology neuroscience science

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Structurally-Constrained Relationships between Cognitive States in the Human Brain
The anatomical connectivity of the human brain supports diverse patterns of correlated neural activity that are thought to underlie cognitive function. In a manner sensitive to underlying structural brain architecture, we examine the extent to which such patterns of correlated activity systematically vary across cognitive states. Anatomical white matter connectivity is compared with functional correlations in neural activity measured via blood oxygen level dependent (BOLD) signals. Functional connectivity is separately measured at rest, during an attention task, and during a memory task. We assess these structural and functional measures within previously-identified resting-state functional networks, denoted task-positive and task-negative networks, that have been independently shown to be strongly anticorrelated at rest but also involve regions of the brain that routinely increase and decrease in activity during task-driven processes. We find that the density of anatomical connections within and between task-positive and task-negative networks is differentially related to strong, task-dependent correlations in neural activity. The space mapped out by the observed structure-function relationships is used to define a quantitative measure of separation between resting, attention, and memory states. We find that the degree of separation between states is related to both general measures of behavioral performance and relative differences in task-specific measures of attention versus memory performance. These findings suggest that the observed separation between cognitive states reflects underlying organizational principles of human brain structure and function.
Full Article

Structurally-Constrained Relationships between Cognitive States in the Human Brain

The anatomical connectivity of the human brain supports diverse patterns of correlated neural activity that are thought to underlie cognitive function. In a manner sensitive to underlying structural brain architecture, we examine the extent to which such patterns of correlated activity systematically vary across cognitive states. Anatomical white matter connectivity is compared with functional correlations in neural activity measured via blood oxygen level dependent (BOLD) signals. Functional connectivity is separately measured at rest, during an attention task, and during a memory task. We assess these structural and functional measures within previously-identified resting-state functional networks, denoted task-positive and task-negative networks, that have been independently shown to be strongly anticorrelated at rest but also involve regions of the brain that routinely increase and decrease in activity during task-driven processes. We find that the density of anatomical connections within and between task-positive and task-negative networks is differentially related to strong, task-dependent correlations in neural activity. The space mapped out by the observed structure-function relationships is used to define a quantitative measure of separation between resting, attention, and memory states. We find that the degree of separation between states is related to both general measures of behavioral performance and relative differences in task-specific measures of attention versus memory performance. These findings suggest that the observed separation between cognitive states reflects underlying organizational principles of human brain structure and function.

Full Article

Filed under cognitive function attention memory neural activity performance psychology neuroscience science

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No such thing as a ‘universal’ intelligence test. Cultural differences determine results country by country 
Researchers at the University of Granada have shown that a universal test of intelligence quotient (IQ) does not exist. Results in this type of test are determined by cultural differences.
Their objective was to study and explain cultural differences in IQ test performance. To do this, scientists from CIMCYC—the University of Granada’s Brain Mind and Behavior Research Center—conducted a study of 54 individuals aged between 18 and 54 years: 27 were Spanish and the other 27 were Moroccans residing in Spain.
The groups were selected to ensure that clear cultural differences existed between them: they spoke different languages (Spanish versus Arabic), professed different religions (Christians versus Muslims), had different traditions, and came from very different geographical contexts (Europe versus Africa).
Both groups underwent different tests of intellectual capacity: for example, a test of non-verbal intelligence, and various neuropsychological tests that measure functions such as visual memory and executive functions.
The same test measures different cognitive functions
Although the two groups were similar in terms of sex, educational level and socio-economic status, the results showed that in the test of non-verbal intelligence, the Spanish group obtained a higher IQ score than the Moroccan group. Moreover, the neuropsychological skills used in each subtest were clearly dependent on the country of origin of each participant. In other words, the same test can measure different cognitive functions in individuals from different cultures.
In the light of the results of this study, the authors suggest that the non-verbal tests cannot be considered culture-free and confirm the importance of validating the tests in their cultural context.
In 2014, this study has been ranked in the top 10 of articles downloaded from Archives of Clinical Neuropsychology.

No such thing as a ‘universal’ intelligence test. Cultural differences determine results country by country

Researchers at the University of Granada have shown that a universal test of intelligence quotient (IQ) does not exist. Results in this type of test are determined by cultural differences.

Their objective was to study and explain cultural differences in IQ test performance. To do this, scientists from CIMCYC—the University of Granada’s Brain Mind and Behavior Research Center—conducted a study of 54 individuals aged between 18 and 54 years: 27 were Spanish and the other 27 were Moroccans residing in Spain.

The groups were selected to ensure that clear cultural differences existed between them: they spoke different languages (Spanish versus Arabic), professed different religions (Christians versus Muslims), had different traditions, and came from very different geographical contexts (Europe versus Africa).

Both groups underwent different tests of intellectual capacity: for example, a test of non-verbal intelligence, and various neuropsychological tests that measure functions such as visual memory and executive functions.

The same test measures different cognitive functions

Although the two groups were similar in terms of sex, educational level and socio-economic status, the results showed that in the test of non-verbal intelligence, the Spanish group obtained a higher IQ score than the Moroccan group. Moreover, the neuropsychological skills used in each subtest were clearly dependent on the country of origin of each participant. In other words, the same test can measure different cognitive functions in individuals from different cultures.

In the light of the results of this study, the authors suggest that the non-verbal tests cannot be considered culture-free and confirm the importance of validating the tests in their cultural context.

In 2014, this study has been ranked in the top 10 of articles downloaded from Archives of Clinical Neuropsychology.

Filed under intelligence cultural differences cognitive function performance psychology neuroscience science

139 notes

Novel Protein Fragments May Protect Against Alzheimer’s
The devastating loss of memory and consciousness in Alzheimer’s disease is caused by plaque accumulations and tangles in neurons, which kill brain cells. Alzheimer’s research has centered on trying to understand the pathology as well as the potential protective or regenerative properties of brain cells as an avenue for treating the widespread disease.
Now Prof. Illana Gozes, the incumbent of the Lily and Avraham Gildor Chair for the Investigation of Growth Factors and director of the Adams Super Center for Brain Studies at the Sackler Faculty of Medicine and a member of Tel Aviv University’s Sagol School of Neuroscience, has discovered novel protein fragments that have proven protective properties for cognitive functioning.
In a study published in the Journal of Alzheimer’s Disease, Prof. Gozes examined the protective effects of two newly discovered protein fragments in mice afflicted with Alzheimer’s disease-like symptoms. Her findings have the potential to serve as a pipeline for new drug candidates to treat the disease.
NAP time for Alzheimer’s
"Several years ago we discovered that NAP, a snippet of a protein essential for brain formation, which later showed efficacy in Phase 2 clinical trials in mild cognitive impairment patients, a precursor to Alzheimer’s," said Prof. Gozes. "Now, we’re investigating whether there are other novel NAP-like sequences in other proteins. This is the question that led us to our discovery."
Prof. Gozes’ research focused on the microtubule network, a crucial part of cells in our bodies. Microtubules act as a transportation system within nerve cells, carrying essential proteins and enabling cell-to-cell communications. But in neurodegenerative diseases like Alzheimer’s, ALS, and Parkinson’s, this network breaks down, hindering motor abilities and cognitive function.
"NAP operates through the stabilization of microtubules — tubes within the cell which maintain cellular shape. They serve as ‘train tracks’ for movement of biological material," said Prof. Gozes. "This is very important to nerve cells, because they have long processes and would otherwise collapse. In Alzheimer’s disease, these microtubules break down. The newly discovered protein fragments, just like NAP before them, work to protect microtubules, thereby protecting the cell."
Down the tubes
In her new study, Prof. Gozes and her team looked at the subunit of the microtubule — the tubulin — and the protein TAU (tubulin-associated unit), important for assembly and maintenance of the microtubule. Abnormal TAU proteins form the tangles that contribute to Alzheimer’s; increased tangle accumulation is indicative of cognitive deterioration. Prof. Gozes decided to test both the tubulin and the TAU proteins for NAP-like sequences. After confirming NAP-like sequences in both tubulin subunits and in TAU, she tested the fragments in tissue cultures for nerve-cell protecting properties against amyloid peptides, the cause of plaque build up in Alzheimer patients’ brains.
"From the tissue culture, we moved to a 10-month-old transgenic mouse model with frontotemporal dementia-like characteristics, which exhibits TAU pathology and cognitive decline," said Prof. Gozes. "We tested one compound — a tubulin fragment — and saw that it protected against cognitive deficits. When we looked at the ‘dementia’-afflicted brain, there was a reduction in the NAP parent protein, but upon treatment with the tubulin fragment, the protein was restored to normal levels."
Prof. Gozes and her team also measured the brain-to-body mass ratio, an indicator of brain degeneration, and saw a significant decrease in the mouse model compared to normal mice. Following the introduction of the tubulin fragments, however, the mouse’s brain to body ratio returned to normal. “We clearly see here the protective effect of the treatment,” said Prof. Gozes. “We witnessed the restorative and protective effects of totally new protein fragments, derived from proteins critical to cell function, in tissue cultures and on animal models.”
(Image: Getty Images)

Novel Protein Fragments May Protect Against Alzheimer’s

The devastating loss of memory and consciousness in Alzheimer’s disease is caused by plaque accumulations and tangles in neurons, which kill brain cells. Alzheimer’s research has centered on trying to understand the pathology as well as the potential protective or regenerative properties of brain cells as an avenue for treating the widespread disease.

Now Prof. Illana Gozes, the incumbent of the Lily and Avraham Gildor Chair for the Investigation of Growth Factors and director of the Adams Super Center for Brain Studies at the Sackler Faculty of Medicine and a member of Tel Aviv University’s Sagol School of Neuroscience, has discovered novel protein fragments that have proven protective properties for cognitive functioning.

In a study published in the Journal of Alzheimer’s Disease, Prof. Gozes examined the protective effects of two newly discovered protein fragments in mice afflicted with Alzheimer’s disease-like symptoms. Her findings have the potential to serve as a pipeline for new drug candidates to treat the disease.

NAP time for Alzheimer’s

"Several years ago we discovered that NAP, a snippet of a protein essential for brain formation, which later showed efficacy in Phase 2 clinical trials in mild cognitive impairment patients, a precursor to Alzheimer’s," said Prof. Gozes. "Now, we’re investigating whether there are other novel NAP-like sequences in other proteins. This is the question that led us to our discovery."

Prof. Gozes’ research focused on the microtubule network, a crucial part of cells in our bodies. Microtubules act as a transportation system within nerve cells, carrying essential proteins and enabling cell-to-cell communications. But in neurodegenerative diseases like Alzheimer’s, ALS, and Parkinson’s, this network breaks down, hindering motor abilities and cognitive function.

"NAP operates through the stabilization of microtubules — tubes within the cell which maintain cellular shape. They serve as ‘train tracks’ for movement of biological material," said Prof. Gozes. "This is very important to nerve cells, because they have long processes and would otherwise collapse. In Alzheimer’s disease, these microtubules break down. The newly discovered protein fragments, just like NAP before them, work to protect microtubules, thereby protecting the cell."

Down the tubes

In her new study, Prof. Gozes and her team looked at the subunit of the microtubule — the tubulin — and the protein TAU (tubulin-associated unit), important for assembly and maintenance of the microtubule. Abnormal TAU proteins form the tangles that contribute to Alzheimer’s; increased tangle accumulation is indicative of cognitive deterioration. Prof. Gozes decided to test both the tubulin and the TAU proteins for NAP-like sequences. After confirming NAP-like sequences in both tubulin subunits and in TAU, she tested the fragments in tissue cultures for nerve-cell protecting properties against amyloid peptides, the cause of plaque build up in Alzheimer patients’ brains.

"From the tissue culture, we moved to a 10-month-old transgenic mouse model with frontotemporal dementia-like characteristics, which exhibits TAU pathology and cognitive decline," said Prof. Gozes. "We tested one compound — a tubulin fragment — and saw that it protected against cognitive deficits. When we looked at the ‘dementia’-afflicted brain, there was a reduction in the NAP parent protein, but upon treatment with the tubulin fragment, the protein was restored to normal levels."

Prof. Gozes and her team also measured the brain-to-body mass ratio, an indicator of brain degeneration, and saw a significant decrease in the mouse model compared to normal mice. Following the introduction of the tubulin fragments, however, the mouse’s brain to body ratio returned to normal. “We clearly see here the protective effect of the treatment,” said Prof. Gozes. “We witnessed the restorative and protective effects of totally new protein fragments, derived from proteins critical to cell function, in tissue cultures and on animal models.”

(Image: Getty Images)

Filed under alzheimer's disease NAP microtubules tau protein brain cells cognitive function neuroscience science

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Researchers capture handoff of tracked object between brain hemispheres
When tracking a moving object, the two halves of the human brain operate much like runners successfully passing a baton during a relay race, says a University of Oregon researcher.
In a study online ahead of print in Current Biology, electroencephalogram (EEG) measured brainwaves from healthy young adults revealed how information about an attended object — one being watched closely — moves from one brain hemisphere to the other.
Such handoffs are necessary because the human visual system is contralateral; objects on the left side of space are processed by the right hemisphere and vice versa. When objects change sides, the two hemispheres must coordinate so that the tracked object isn’t lost during the exchange.
"Attentional tracking is something we do on a regular basis when driving in traffic or walking through a crowd," said Edward K. Vogel, professor of psychology. "Our world is dynamic. We’re moving. Our eyes are moving. Objects are moving. We need to use our attention to follow objects of interest as they move so that we can predict where they are going.”
People experience a smooth and seamless visual world despite information quickly being transferred back and forth between the hemispheres. “A car in your rearview mirror that moves from one lane to the other doesn’t suddenly disappear and then reappear on the other side,” he said. “The exchange is smooth, in part, because often the hemispheres coordinate a soft handoff.”
That means, he said, that before the object crosses into the other side of space, the new hemisphere picks it up, and the old hemisphere continues to hang on to it until it crosses well into the other side of space. Both hemispheres grab hold of the object during the exchange — much like in a relay race when two runners both briefly have hold of the baton to assure it isn’t dropped.
Eventually, Vogel said, such research may help us better understand individual differences in people’s visual tracking abilities. Some people, for instance, have trouble picking up a moving vehicle seen in a rearview mirror once it enters a blind spot. “This new technique allows us to watch the brain as information about a target is handed off from one side to the other, and it may provide insights into why attention is so limited,” Vogel said.
While psychological studies have often looked at attention and awareness, there has been little focus on how the two hemispheres interact. Interestingly, Vogel said, cellphone companies have long studied a similar problem: how to best transfer a call’s signal while a customer moves from one zone of a cell tower to another.
Cellular carriers using Code Division Multiple Access (CDMA) such as Sprint and Verizon utilize a soft handoff between towers, similar to the new findings. Global System for Mobile (GSM) carriers, such as T-Mobile and ATT, use a hard handoff in which a signal leaving a tower’s coverage is rapidly shut off and then turned on by the next tower — a scenario that tended to, before the technology improved, result in more dropped calls.
"Researchers at the University of Oregon are using cutting-edge techniques to examine important mechanisms of cognitive functioning," said Kimberly Andrews Espy, vice president for research and innovation and dean of the UO Graduate School. "This research by Dr. Vogel and his team provides a window on the process of attentional tracking that furthers our understanding of how the two hemispheres of the brain work together to process visual information."

Researchers capture handoff of tracked object between brain hemispheres

When tracking a moving object, the two halves of the human brain operate much like runners successfully passing a baton during a relay race, says a University of Oregon researcher.

In a study online ahead of print in Current Biology, electroencephalogram (EEG) measured brainwaves from healthy young adults revealed how information about an attended object — one being watched closely — moves from one brain hemisphere to the other.

Such handoffs are necessary because the human visual system is contralateral; objects on the left side of space are processed by the right hemisphere and vice versa. When objects change sides, the two hemispheres must coordinate so that the tracked object isn’t lost during the exchange.

"Attentional tracking is something we do on a regular basis when driving in traffic or walking through a crowd," said Edward K. Vogel, professor of psychology. "Our world is dynamic. We’re moving. Our eyes are moving. Objects are moving. We need to use our attention to follow objects of interest as they move so that we can predict where they are going.”

People experience a smooth and seamless visual world despite information quickly being transferred back and forth between the hemispheres. “A car in your rearview mirror that moves from one lane to the other doesn’t suddenly disappear and then reappear on the other side,” he said. “The exchange is smooth, in part, because often the hemispheres coordinate a soft handoff.”

That means, he said, that before the object crosses into the other side of space, the new hemisphere picks it up, and the old hemisphere continues to hang on to it until it crosses well into the other side of space. Both hemispheres grab hold of the object during the exchange — much like in a relay race when two runners both briefly have hold of the baton to assure it isn’t dropped.

Eventually, Vogel said, such research may help us better understand individual differences in people’s visual tracking abilities. Some people, for instance, have trouble picking up a moving vehicle seen in a rearview mirror once it enters a blind spot. “This new technique allows us to watch the brain as information about a target is handed off from one side to the other, and it may provide insights into why attention is so limited,” Vogel said.

While psychological studies have often looked at attention and awareness, there has been little focus on how the two hemispheres interact. Interestingly, Vogel said, cellphone companies have long studied a similar problem: how to best transfer a call’s signal while a customer moves from one zone of a cell tower to another.

Cellular carriers using Code Division Multiple Access (CDMA) such as Sprint and Verizon utilize a soft handoff between towers, similar to the new findings. Global System for Mobile (GSM) carriers, such as T-Mobile and ATT, use a hard handoff in which a signal leaving a tower’s coverage is rapidly shut off and then turned on by the next tower — a scenario that tended to, before the technology improved, result in more dropped calls.

"Researchers at the University of Oregon are using cutting-edge techniques to examine important mechanisms of cognitive functioning," said Kimberly Andrews Espy, vice president for research and innovation and dean of the UO Graduate School. "This research by Dr. Vogel and his team provides a window on the process of attentional tracking that furthers our understanding of how the two hemispheres of the brain work together to process visual information."

Filed under cognitive function cerebral hemispheres attentional tracking motion perception neuroscience science

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