Researchers publish first study of brain activation in MS using fNIRS

Using functional near infrared spectroscopy (fNIRS), Kessler Foundation researchers have shown differential brain activation patterns between people with multiple sclerosis (MS) and healthy controls. This is the first MS study in which brain activation was studied using fNIRS while participants performed a cognitive task. The article, “Neuroimaging and cognition using functional near infrared spectroscopy (fNIRS) in multiple sclerosis,” was published online on June 11 by Brain Imaging and Behavior. Authors are Jelena Stojanovic-Radic, PhD, Glenn Wylie, DPhil, Gerald Voelbel, PhD, Nancy Chiaravalloti, PhD, and John DeLuca, PhD.

Researchers compared 13 individuals with MS with 12 controls for their performance on a working memory task with four levels of difficulty. Most such studies have employed functional magnetic resonance imaging (fMRI); fNIRS has been used infrequently in clinical populations, and has not been applied previously to neuroimaging research in MS.  Studies comparing fMRI findings with those of fNIRS, however, show broad agreement in terms of activation patterns.

Results showed differences in activation between the groups that were dependent on task load. The MS group had an increase in activation at low task difficulty and a decrease in activation at high task difficulty. Conversely, in the control group, activation decreased with low task difficulty and increased with high task difficulty. Performance accuracy was lower in the MS group for low task load; there were no differences between the groups at the higher task loads.  

“The data we obtained via fNIRS are consistent with fMRI data for clinical populations. We demonstrated that fNIRS is capable of detecting neuronal activation with a reasonable degree of detail,” noted Glenn Wylie, DPhil, associate director of Neuroscience and the Neuroimaging Center at Kessler Foundation. “We attribute the differences in brain activation patterns to the effort expended during the working memory task rather than to differences in speed of processing,” he added. “Because fNIRS is more portable and easier to use that fMRI, it may offer advantages in monitoring cognitive interventions that require frequent scans.”

In addition to working memory, future research in clinical populations should focus on processing speed and episodic memory, cognitive functions that are also affected in MS.

(Image credit)

In our world of ingrained literacy, thinking and writing seem scarcely related activities. We can imagine the latter depending on the former, but surely not the other way around: everyone thinks, whether or not they write. But Havelock was right. The written word – the persistent word – was a prerequisite for conscious thought as we understand it.
—  James Gleick
Intelligent whites give more enlightened responses than less intelligent whites to questions about their attitudes, but their responses to questions about actual policies aimed at redressing racial discrimination are far less enlightened. For example, although nearly all whites with advanced cognitive abilities say that ‘whites have no right to segregate their neighborhoods,’ nearly half of this group remains content to allow prejudicial real estate practices to continue unencumbered by open housing laws.

Humans not smarter than animals, just different, experts say

Humans have been deceiving themselves for thousands of years that they’re smarter than the rest of the animal kingdom, despite growing evidence to the contrary, according to University of Adelaide experts in evolutionary biology.

"For millennia, all kinds of authorities – from religion to eminent scholars – have been repeating the same idea ad nauseam, that humans are exceptional by virtue that they are the smartest in the animal kingdom," says Dr Arthur Saniotis, Visiting Research Fellow with the University’s School of Medical Sciences.

"However, science tells us that animals can have cognitive faculties that are superior to human beings."

[read more]

Awake within a dream: lucid dreamers show greater insight in waking life

People who are aware they are asleep when they are dreaming have better than average problem-solving abilities, new research has discovered.

image

Experts from the University of Lincoln, UK, say that those who experience ‘lucid dreaming’ – a phenomena where someone who is asleep can recognise that they are dreaming – can solve problems in the waking world better than those who remain unaware of the dream until they wake up.

The concept of lucid dreaming was explored in the 2010 film Inception, where the dreamers were able to spot incongruities within their dream. It is thought some people are able to do this because of a higher level of insight, meaning their brains detect they are in a dream because events would not make sense otherwise. This cognitive ability translates to the waking world when it comes to finding the solution to a problem by spotting hidden connections or inconsistencies, researchers say.

The research was carried out by Dr Patrick Bourke, Senior Lecturer at the Lincoln School of Psychology and his student Hannah Shaw. It is the first empirical study demonstrating the relationship between lucid dreaming and insight.

He said: “It is believed that for dreamers to become lucid while asleep, they must see past the overwhelming reality of their dream state, and recognise that they are dreaming.

“The same cognitive ability was found to be demonstrated while awake by a person’s ability to think in a different way when it comes to solving problems.”

The study examined 68 participants aged between 18 and 25 who had experienced different levels of lucid dreaming, from never to several times a month. They were asked to solve 30 problems designed to test insight. Each problem consisted of three words and a solution word.

Each of the three words could be combined with the solution word to create a new compound word.

For example with the words ‘sand’, ‘mile’ and ‘age’, the linking word would be ‘stone’.

Results showed that frequent lucid dreamers solved 25 per cent more of the insight problems than the non-lucid dreamers.

Miss Shaw, who conducted the research as part of her undergraduate dissertation, said the ability to experience lucid dreams is something that can be learned. “We aren’t entirely sure why some people are naturally better at lucid dreaming than others, although it is a skill which can be taught,” said Hannah.

“For example you can get into the habit of asking yourself “is this a dream?”. If you do this during the day when you are awake and make it a habit then it can transfer to when you are in a dream.”

Our awareness of our own speech often comes after the words have left our mouth, not before.

-

If you think you know what you just said, think again. People can be tricked into believing they have just said something they did not, researchers report this week.The dominant model of how speech works is that it is planned in advance — speakers begin with a conscious idea of exactly what they are going to say. But some researchers think that speech is not entirely planned, and that people know what they are saying in part through hearing themselves speak. So cognitive scientist Andreas Lind and his colleagues at Lund University in Sweden wanted to see what would happen if someone said one word, but heard themselves saying another. “If we use auditory feedback to compare what we say with a well-specified intention, then any mismatch should be quickly detected,” he says. “But if the feedback is instead a powerful factor in a dynamic, interpretative process, then the manipulation could go undetected.” In Lind’s experiment, participants took a Stroop test — in which a person is shown, for example, the word ‘red’ printed in blue and is asked to name the colour of the type (in this case, blue). During the test, participants heard their responses through headphones. The responses were recorded so that Lind could occasionally play back the wrong word, giving participants auditory feedback of their own voice saying something different from what they had just said. Lind chose the words ‘grey’ and ‘green’ (grå and grön in Swedish) to switch, as they sound similar but have different meanings. After participants heard a manipulated word, a question popped up on the screen asking what they had just said, and they were also quizzed after the test to see whether they had detected the switch. When the voice-activated software got the timing just right — so that the wrong word began within 5–20 milliseconds of the participant starting to speak — the change went undetected more than two-thirds of the time. And in 85% of undetected substitutions, the participant accepted that they had said the wrong word, indicating that speakers listen to their own voices to help specify the meaning of what they are saying. The remaining 15% didn’t notice the manipulations, but also didn’t seem to notice that the word had changed, and Lind says it is unclear why. The results are published this week in Psychological Science.

Ability to ‘think about thinking’ not limited to humans

Humans’ closest animal relatives, chimpanzees, have the ability to “think about thinking” – what is called “metacognition,” according to new research by scientists at Georgia State University and the University at Buffalo.

Michael J. Beran and Bonnie M. Perdue of the Georgia State Language Research Center (LRC) and J. David Smith of the University at Buffalo conducted the research, published in the journal Psychological Science of the Association for Psychological Science.

"The demonstration of metacognition in nonhuman primates has important implications regarding the emergence of self-reflective mind during humans’ cognitive evolution," the research team noted.

Metacognition is the ability to recognize one’s own cognitive states. For example, a game show contestant must make the decision to “phone a friend” or risk it all, dependent on how confident he or she is in knowing the answer.

"There has been an intense debate in the scientific literature in recent years over whether metacognition is unique to humans," Beran said.

Chimpanzees at Georgia State’s LRC have been trained to use a language-like system of symbols to name things, giving researchers a unique way to query animals about their states of knowing or not knowing.

In the experiment, researchers tested the chimpanzees on a task that required them to use symbols to name what food was hidden in a location. If a piece of banana was hidden, the chimpanzees would report that fact and gain the food by touching the symbol for banana on their symbol keyboards.

But then, the researchers provided chimpanzees either with complete or incomplete information about the identity of the food rewards.

In some cases, the chimpanzees had already seen what item was available in the hidden location and could immediately name it by touching the correct symbol without going to look at the item in the hidden location to see what it was.

In other cases, the chimpanzees could not know what food item was in the hidden location, because either they had not seen any food yet on that trial, or because even if they had seen a food item, it may not have been the one moved to the hidden location.

In those cases, they should have first gone to look in the hidden location before trying to name any food.

In the end, chimpanzees named items immediately and directly when they knew what was there, but they sought out more information before naming when they did not already know.

The research team said, “This pattern of behavior reflects a controlled information-seeking capacity that serves to support intelligent responding, and it strongly suggests that our closest living relative has metacognitive abilities closely related to those of humans.”

PSYCHOGRAPHY

[noun]

1. a description of the phenomena of mind; mapping thoughts.

2. the reception of written spirit messages through a medium; spirit writing. 

3. the production of images of spirits on film without the use of a camera, believed to be caused by spiritualistic forces.

Etymology: Greek ‘psych-’ (mind, spirit, consciousness; mental processes; the human soul; breath of life; literally, “that which breathes” or “breathing”) + -graphia (writing).

[Michael Birnstingl]

Train your heart to protect your mind

Exercising to improve our cardiovascular strength may protect us from cognitive impairment as we age, according to a new study by researchers at the University of Montreal and its affiliated Institut universitaire de gératrie de Montréal Research Centre. “Our body’s arteries stiffen with age, and the vessel hardening is believed to begin in the aorta, the main vessel coming out of the heart, before reaching the brain. Indeed, the hardening may contribute to cognitive changes that occur during a similar time frame,” explained Claudine Gauthier, first author of the study. “We found that older adults whose aortas were in a better condition and who had greater aerobic fitness performed better on a cognitive test. We therefore think that the preservation of vessel elasticity may be one of the mechanisms that enables exercise to slow cognitive aging.”

The researchers worked with 31 young people between the ages of 18 and 30 and 54 older participants aged between 55 and 75. This enabled the team to compare the older participants within their peer group and against the younger group who obviously have not begun the aging processes in question. None of the participants had physical or mental health issues that might influence the study outcome. Their fitness was tested by exhausting the participants on a workout machine and determining their maximum oxygen intake over a 30 second period. Their cognitive abilities were assessed with the Stroop task. The Stroop task is a scientifically validated test that involves asking someone to identify the ink colour of a colour word that is printed in a different colour (e.g. the word red could be printed in blue ink and the correct answer would be blue). A person who is able to correctly name the colour of the word without being distracted by the reflex to read it has greater cognitive agility.

The participants undertook three MRI scans: one to evaluate the blood flow to the brain, one to measure their brain activity as they performed the Stroop task, and one to actually look at the physical state of their aorta. The researchers were interested in the brain’s blood flow, as poorer cardiovascular health is associated with a faster pulse wave,at each heartbeat which in turn could cause damage to the brain’s smaller blood vessels. “This is first study to use MRI to examine participants in this way,” Gauthier said. “It enabled us to find even subtle effects in this healthy population, which suggests that other researchers could adapt our test to study vascular-cognitive associations within less healthy and clinical populations.”

The results demonstrated age-related declines in executive function, aortic elasticity and cardiorespiratory fitness, a link between vascular health and brain function, and a positive association between aerobic fitness and brain function. “The link between fitness and brain function may be mediated through preserved cerebrovascular reactivity in periventricular watershed areas that are also associated with cardiorespiratory fitness,” Gauthier said. “Although the impact of fitness on cerebral vasculature may however involve other, more complex mechanisms, overall these results support the hypothesis that lifestyle helps maintain the elasticity of arteries, thereby preventing downstream cerebrovascular damage and resulting in preserved cognitive abilities in later life.”

A universal difference

The author of Crazy Like Us, Ethan Watters, has written an excellent article on whether there’s such a thing as ‘human nature’ for the latest edition of Adbusters.

The piece tackles how scientific assumptions about the ‘universals’ of the human mind are having to be revised and discusses research which has shown how people from across the world behave markedly differently in supposedly culturally neutral tasks.

The last generation or two of undergraduates have largely been taught by a cohort of social scientists busily doing penance for the racism and Eurocentrism of their predecessors, albeit in different ways. Many anthropologists took to the navel gazing of postmodernism and swore off attempts at rationality and science, which were disparaged as weapons of cultural imperialism.

Economists and psychologists skirted the issue with the convenient assumption that their job was to study the human mind stripped of culture. The human brain is genetically comparable around the globe, it was agreed, so human hardwiring for much behavior, perception, and cognition should be similarly universal. No need, in that case, to look beyond the convenient population of undergraduates for test subjects…

Henrich’s work with the ultimatum game emerged from a small but growing counter trend in the social sciences, one in which researchers look straight at the question of how deeply culture shapes human cognition.

The article is an engaging look at this new wave of research.

Source: mindhacks.com
Original article: Is There Such a Thing as “Human Nature”?

2

How Intense Study May Harm Our Workouts

Tire your brain and your body may follow, a remarkable new study of mental fatigue finds. Strenuous mental exertion may lessen endurance and lead to shortened workouts, even if, in strict physiological terms, your body still has plenty of energy reserves.

Scientists have long been intrigued by the idea that physical exertion affects our ability to think, with most studies finding that short bouts of exercise typically improve cognition. Prolonged and exhausting physical exercise, on the other hand, may leave practitioners too worn out to think clearly, at least for a short period of time.

But the inverse possibility — that too much thinking might impair physical performance — has received far less attention. So scientists from the University of Kent in England and the French Institute of Health and Medical Research, known as INSERM, joined forces to investigate the matter. For a study published online in May in Medicine & Science in Sports & Exercise, they decided to tire volunteers’ brains with a mentally demanding computer word game and see how well their bodies would perform afterward.

Fatigue is a complex, multifaceted condition. Exercise science usually concentrates on bodily fatigue, meaning a reduction in our ability to contract muscles and stay in motion. Run, cycle, lift weights or just stand, and a small army of muscles contract, burning fuel and eventually tiring. This fatigue occurs both within the individual muscles and at the level of the nervous system, a condition known as central fatigue.

Our minds tire, too, although the causes are difficult to pin down. Neurons may run low of fuel, and other processes probably also are involved. But it is clear, as many of us know from personal experience, that concentrating intensively on an intellectually demanding project for hours typically leaves you feeling mentally dull.

To determine the impact that such mental fatigue might have on subsequent exercise, the researchers first asked 10 healthy, active young men to visit an exercise lab on several occasions. During each visit, the men began by having monitors and an electrode attached to one leg and then vigorously contracting their leg muscles, while the electrode zapped a small amount of electricity into the muscles, augmenting their effort so that they reached their maximum contractile force at that moment. Tired muscles would be expected to produce less force and respond more feebly to the electrical zapping, telling scientists to what degree the body has developed both localized and central fatigue.

Then, during one session, the men sat for 90 minutes before a computer screen, intently watching individual letters flash by while they counted every four and punched various keys, depending on how each grouping of the letters was configured. This test is known reliably to induce mental fatigue.

During a separate lab visit, the men watched “Earth,” a serene, calming documentary, for 90 minutes.

After both intellectual activities, the men exercised one of their legs at a specialized one-legged ergometer to the point of muscular exhaustion, while frequently telling the researchers how strenuous the exercise felt.

Then they underwent the test of actual maximum contractile force one more time.

As it turned out, mental fatigue significantly affected the men’s endurance. They tired about 13 percent faster after the computer test than after watching “Earth.” They also reported that the workout felt far more taxing.

But, interestingly, their maximum contractile force was about the same after each session. Their muscles responded just as robustly to orders from the brain and the attached electrode after the draining mental workout as after the quiet session, even though the brain-fogged volunteers felt as if their muscles were much more exhausted.

This finding suggests “that maximal force production is not altered by mental fatigue but endurance performance is altered, and this alteration is closely linked with a higher feeling of perceived exertion,” said Romuald Lepers, a professor at the INSERM research laboratory at the University of Burgundy in France and, with Samuele M. Marcora and Benjamin Pageaux of the University of Kent, co-author of the study.

In simpler terms, exercise simply feels harder when your brain is tired, so you quit earlier, although objectively, your muscles are still somewhat fresh.

This finding has multiple implications for how we combine ratiocination and sweat. It suggests, for instance, that the morning of an important race or challenging training session may not be the ideal time to finish your taxes, since overthinking could lead to underperforming physically.

Inversely, the results also suggest that “training our brain to avoid or limit mental fatigue” could be a hitherto untapped means of improving physical performance, Dr. Lepers said. Training yourself to speed through crossword puzzles, in other words, might improve your workouts, by subtly altering how mind and muscles communicate and making your brain less likely to consider your muscles easily enfeebled.

But that possibility hasn’t been tested, Dr. Lepers said. For now, his study’s most compelling conclusion is that, as he says, “our feelings do not always reflect our physiological state” and our bodies may in many instances be sturdier than own minds realize, an idea worth thinking about.

2

‘Sticky synapses’ can impair new memories by holding on to old ones

A team of UBC neuroscientists has found that synapses that are too strong or ‘sticky’ can actually hinder our capacity to learn new things.

University of British Columbia researchers have discovered that so-called “sticky synapses” in the brain can impair new learning by excessively hard-wiring old memories and inhibiting our ability to adapt to our changing environment.

Memories are formed by strong synaptic connections between nerve cells. Now a team of UBC neuroscientists has found that synapses that are too strong or “sticky” can actually hinder our capacity to learn new things by affecting cognitive flexibility, the ability to modify our behaviours to adjust to circumstances that are similar, but not identical, to previous experiences.

“We tend to think that strong retention of memories is always a good thing,” says Fergil Mills, UBC PhD candidate and the study’s first author. “But our study shows that cognitive flexibility involves actively weakening old memory traces. In certain situations, you have to be able to ‘forget’ to learn.”

The study, published today in the Proceedings of the National Academy of Sciences, shows that mice with excessive beta-catenin – a protein that is part of the “molecular glue” that holds synapses together – can learn a task just as well as normal mice, but lacked the mental dexterity to adapt if the task was altered.

“Increased levels of beta-catenin have previously been reported in disorders such as Alzheimer’s disease and Huntington’s disease, and, intriguingly, patients with these diseases have been shown to have deficits in cognitive flexibility similar to those we observed in this study,” says Shernaz Bamji, an associate professor in UBC’s Dept. of Cellular and Physiological Sciences.

“Now, we see that changes in beta-catenin levels can dramatically affect learning and memory, and may indeed play a role in the cognitive deficits associated with these diseases,” she adds. “This opens up many exciting new avenues for research into these diseases and potential therapeutic approaches.”

BACKGROUND

To test cognitive flexibility in mice, researchers conducted an experiment where the mice were placed in a pool of water and had to learn to find a submerged hidden platform. The mice with excessive beta-catenin could learn to find the platform just as well as normal mice. However, if the platform was moved to a different location in the pool, these mice kept swimming to the platform’s previous location. Even after many days of training, the ‘sticky synapses’ in their brains made them unable to effectively learn to find the new platform.

Ability To ‘Think About Thinking’ Not Limited Only To Humans

Humans’ closest animal relatives, chimpanzees, have the ability to “think about thinking” – what is called “metacognition,” according to new research by scientists at Georgia State University and the University at Buffalo.

“The demonstration of metacognition in nonhuman primates has important implications regarding the emergence of self-reflective mind during humans’ cognitive evolution,” […] “There has been an intense debate in the scientific literature in recent years over whether metacognition is unique to humans,” the research team noted.

Chimpanzees at Georgia State’s LRC have been trained to use a language-like system of symbols to name things, giving researchers a unique way to query animals about their states of knowing or not knowing. In the experiment, researchers tested the chimpanzees on a task that required them to use symbols to name what food was hidden in a location. If a piece of banana was hidden, the chimpanzees would report that fact and gain the food by touching the symbol for banana on their symbol keyboards. But then, the researchers provided chimpanzees either with complete or incomplete information about the identity of the food rewards.

In some cases, the chimpanzees had already seen what item was available in the hidden location and could immediately name it by touching the correct symbol without going to look at the item in the hidden location to see what it was. In other cases, the chimpanzees could not know what food item was in the hidden location, because either they had not seen any food yet on that trial, or because even if they had seen a food item, it may not have been the one moved to the hidden location. In those cases, they should have first gone to look in the hidden location before trying to name any food.

In the end, chimpanzees named items immediately and directly when they knew what was there, but they sought out more information before naming when they did not already know.

The research team said, “This pattern of behavior reflects a controlled information-seeking capacity that serves to support intelligent responding, and it strongly suggests that our closest living relative has metacognitive abilities closely related to those of humans.”

Source: gsu.edu
Image: [x]

Bee brains challenge view that larger brains are superior at understanding conceptual relationships

The humble honeybee may not seem very intelligent at first sight, but recent research has shown that it possesses a surprising degree of sophistication that is not expected in an insect brain. Specifically, the honeybee can understand conceptual relationships such as “same/different” and “above/below” that rely on relationships between objects rather than simply the physical features of objects.

In primates, this ability to understand conceptual relationships is attributed to neuronal activity in the prefrontal cortex (PFC). However, honeybees don’t have PFCs. Their brains are so small and lacking in complex brain structures that scientists have traditionally thought that the ability to understand conceptual relationships was beyond them.

Scientists Aurore Avarguès-Weber and Martin Giurfa, both from the University of Toulouse and CNRS in Toulouse, France, have analyzed the implications of the honeybee’s ability to understand conceptual relationships, and have published a paper on the subject in a recent issue of Proceedings of the Royal Society B.

"One thing that should be clear from this analysis is that, although it is always a matter of debate what is unique to humans and what to animals, these results show at least something that is not," Giurfa told Phys.org. "While the capacity of conceptual elaboration has been considered (and is still considered) a higher-order capacity proper from primates and other ‘highly-evolved’ animals (the quotes are ironic in this case), the fact that a 950 000-neuron [honeybee] brain can achieve this kind of task shows that the frontier does not reside there.

"The obvious question would be then, what brings as advantage a 100-billion-neuron [human] brain? Obviously several advantages can be cited: language, for instance. Consciousness, whose existence is a matter of debate and of investigation in animals. And the idea that human brains have perhaps replicated redundant and modifiable modules to solve problems that small brains solve with single microcircuits at a smaller scale."

[read more]

2

The social origins of intelligence in the brain
-
A study of brain injuries in vets showed that brain regions that contribute to optimal social functioning are also vital to general intelligence and emotional intelligence
-
By studying the injuries and aptitudes of Vietnam War veterans who suffered penetrating head wounds during the war, researchers have found that brain regions that contribute to optimal social functioning are also vital to general intelligence and emotional intelligence. This finding, reported in the journal Brain, bolsters the view that general intelligence emerges from the emotional and social context of one’s life. “We are trying to understand the nature of general intelligence and to what extent our intellectual abilities are grounded in social cognitive abilities,” said Aron Barbey, a University of Illinois professor of neuroscience, psychology, and speech and hearing science. Barbey, an affiliate of the Beckman Institute and he Institute for Genomic Biology at the University of Illinois, led the new study with an international team of collaborators.

Studies in social psychology indicate that human intellectual functions originate from the social context of everyday life, Barbey said. “We depend at an early stage of our development on social relationships — those who love us care for us when we would otherwise be helpless.”

Social interdependence continues into adulthood and remains important throughout the lifespan. “Our friends and family tell us when we could make bad mistakes and sometimes rescue us when we do.

“And so the idea is that the ability to establish social relationships and navigate the social world is not secondary to a more general cognitive capacity for intellectual function, but that it may be the other way around. Intelligence may originate from the central role of relationships in human life and therefore may be tied to social and emotional capacities.”

(via The social origins of intelligence in the brain | KurzweilAI)

Text
Photo
Quote
Link
Chat
Audio
Video