T. Rex not as smart as previously claimed

Dinosaurs were as smart as reptiles but not as intelligent as monkeys, as former research suggests.

An international team of palaeontologists, behavioural scientists and neurologists have re-examined brain size and structure in dinosaurs and concluded they behaved more like crocodiles and lizards.

In a study published last year, it was claimed that dinosaurs like T. rex had an exceptionally high number of neurons and were substantially more intelligent than assumed. It was claimed that these high neuron counts could directly inform on intelligence, metabolism and life history, and that T. rex was rather monkey-like in some of its habits. Cultural transmission of knowledge as well as tool use were cited as examples of cognitive traits that it might have possessed.

However the new study, published today in The Anatomical Record, involving the University of Bristol's Hady George, Dr Darren Naish (University of Southampton) and led by Dr Kai Caspar (Heinrich Heine University) with Dr Cristian Gutierrez-Ibanez (University of Alberta) and Dr Grant Hurlburt (Royal Ontario Museum) takes a closer look at techniques used to predict both brain size and neuron numbers in dinosaur brains. The team found that previous assumptions about brain size in dinosaurs, and the number of neurons their brains contained, were unreliable.

The research follows decades of analysis in which palaeontologists and biologists have examined dinosaur brain size and anatomy, and used these data to infer behaviour and lifestyle. Information on dinosaur brains comes from mineral infillings of the brain cavity, termed endocasts, as well as the shapes of the cavities themselves.

The team found that their brain size had been overestimated -- especially that of the forebrain -- and thus neuron counts as well. In addition, they show that neuron count estimates are not a reliable guide to intelligence.

To reliably reconstruct the biology of long-extinct species, the team argues, researchers should look at multiple lines of evidence, including skeletal anatomy, bone histology, the behaviour of living relatives, and trace fossils. "Determining the intelligence of dinosaurs and other extinct animals is best done using many lines of evidence ranging from gross anatomy to fossil footprints instead of relying on neuron number estimates alone," explained Hady from Bristol's School of Earth Sciences.

Dr Kai Caspar explained: "We argue that it's not good practice to predict intelligence in extinct species when neuron counts reconstructed from endocasts are all we have to go on."

"Neuron counts are not good predictors of cognitive performance, and using them to predict intelligence in long-extinct species can lead to highly misleading interpretations," added Dr Ornella Bertrand (Institut Català de Paleontologia Miquel Crusafont).

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Can animals count?

Research co-led by neuroscientists Professor Yung Wing-ho from City University of Hong Kong (CityUHK) and Professor Ke Ya from The Chinese University of Hong Kong (CUHK) Faculty of Medicine (CU Medicine) has made a groundbreaking discovery regarding number sense in animals by confirming the existence of discrete number sense in rats, offering a crucial animal model for investigating the neural basis of numerical ability and disability in humans.

The research team has developed an innovative approach that employs a novel numerical learning task, brain manipulation techniques and artificial intelligence modelling, and that resolves an ongoing argument about whether rats have a sense of numbers. The study sheds light on the mechanisms underlying numerical ability. The findings have been published in the renowned multidisciplinary scientific journal Science Advances.

Number sense closely linked to survival and intelligence

Number sense is a fundamental ability in animals' perception of the world and increases their chances of survival. It is also an important cognitive ability, which is fundamental to mathematical aptitude, a hallmark of human intelligence. About 3% to 7% of people suffer from dyscalculia, a learning disability that affects the ability to learn arithmetic and mathematics of people of normal intelligence; a deficit in number sense is one of the major symptoms.

Number sense refers to the capability to compare, estimate and manipulate nonsymbolic numerical quantities, rather than associated magnitudes, which are continuous dimensions inherent in a group of items, such as the area of visual objects or the duration of sound pulses. There have been challenges regarding whether number sense can be assessed in isolation from the influence of continuous magnitudes. Also, there has been a vivid ongoing debate regarding whether the sense of magnitude or the sense of number is more fundamental.

Study confirms that the rat brain has a specific area for dealing with numbers

The research team minimised the influence of continuous magnitudes in numerical tests and conducted meticulous quantitative analyses in the study to determine the respective contributions of numbers and magnitudes. They developed an algorithm to generate stimuli that enable animals to focus only on numbers, minimising other distracting factors. This will help scientists better understand how animals perceive and quantify numbers.

The study found that rats without any previous knowledge of numbers were able to develop a sense of numbers when trained with sounds representing two or three numbers. Despite the influence of continuous magnitudes, the rats consistently focused on the number of sounds when making choices for food rewards.

Professor Yung, Associate Dean of the Jockey Club College of Veterinary Medicine and Life Sciences and Chair Professor of Cognitive Neuroscience at CityUHK, said, "Our study helps dissect the relationship between magnitude and numerosity processing. We discovered that when we blocked a specific part of the rats' brain, called the posterior parietal cortex, their ability to understand numbers was affected but not their sense of magnitude. This suggests that the brain has a specific area for dealing with numbers. In fact, this is the first time scientists have demonstrated that rats have the ability to discriminate and categorise three different numbers in a single test, surpassing a simple quantity comparison."

Professor Ke from the School of Biomedical Sciences at CU Medicine expressed excitement about the findings. "The study not only solves a long-standing mystery about how brains handle numbers, but also offers new insights into studying the specific neural circuits involved in number processing in animals and how genes are associated with mathematical ability," she said. "Furthermore, the findings from neural network modelling could have practical applications in the field of artificial intelligence. In the future, our increased understanding of the brain mechanisms underlying the processing of numbers may contribute to the development of interventions for individuals with numerical difficulties."

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Lack of focus doesn't equal lack of intelligence -- it's proof of an intricate brain

Imagine a busy restaurant: dishes clattering, music playing, people talking loudly over one another. It's a wonder that anyone in that kind of environment can focus enough to have a conversation. A new study by researchers at Brown University's Carney Institute for Brain Science provides some of the most detailed insights yet into the brain mechanisms that help people pay attention amid such distraction, as well as what's happening when they can't focus.

In an earlier psychology study, the researchers established that people can separately control how much they focus (by enhancing relevant information) and how much they filter (by tuning out distraction). The team's new research, published in Nature Human Behaviour, unveils the process by which the brain coordinates these two critical functions.

Lead author and neuroscientist Harrison Ritz likened the process to how humans coordinate muscle activity to perform complex physical tasks.

"In the same way that we bring together more than 50 muscles to perform a physical task like using chopsticks, our study found that we can coordinate multiple different forms of attention in order to perform acts of mental dexterity," said Ritz, who conducted the study while a Ph.D. student at Brown.

The findings provide insight into how people use their powers of attention as well as what makes attention fail, said co-author Amitai Shenhav, an associate professor in Brown's Department of Cognitive, Linguistic and Psychological Sciences.

"These findings can help us to understand how we as humans are able to exhibit such tremendous cognitive flexibility -- to pay attention to what we want, when we want to," Shenhav said. "They can also help us better understand limitations on that flexibility, and how limitations might manifest in certain attention-related disorders such as ADHD."

The focus-and-filter test

To conduct the study, Ritz administered a cognitive task to participants while measuring their brain activity in an fMRI machine. Participants saw a swirling mass of green and purple dots moving left and right, like a swarm of fireflies. The tasks, which varied in difficulty, involved distinguishing between the movement and colors of the dots. For example, participants in one exercise were instructed to select which color was in the majority for the rapidly moving dots when the ratio of purple to green was almost 50/50.

Ritz and Shenhav then analyzed participants' brain activity in response to the tasks.

Ritz, who is now a postdoctoral fellow at the Princeton Neuroscience Institute, explained how the two brain regions work together during these types of tasks.

"You can think about the intraparietal sulcus as having two knobs on a radio dial: one that adjusts focusing and one that adjusts filtering," Ritz said. "In our study, the anterior cingulate cortex tracks what's going on with the dots. When the anterior cingulate cortex recognizes that, for instance, motion is making the task more difficult, it directs the intraparietal sulcus to adjust the filtering knob in order to reduce the sensitivity to motion.

"In the scenario where the purple and green dots are almost at 50/50, it might also direct the intraparietal sulcus to adjust the focusing knob in order to increase the sensitivity to color. Now the relevant brain regions are less sensitive to motion and more sensitive to the appropriate color, so the participant is better able to make the correct selection."

Ritz's description highlights the importance of mental coordination over mental capacity, revealing an often-expressed idea to be a misconception.

"When people talk about the limitations of the mind, they often put it in terms of, 'humans just don't have the mental capacity' or 'humans lack computing power,'" Ritz said. "These findings support a different perspective on why we're not focused all the time. It's not that our brains are too simple, but instead that our brains are really complicated, and it's the coordination that's hard."

Ongoing research projects are building on these study findings. A partnership with physician-scientists at Brown University and Baylor College of Medicine is investigating focus-and-filter strategies in patients with treatment-resistant depression. Researchers in Shenhav's lab are looking at the way motivation drives attention; one study co-led by Ritz and Brown Ph.D. student Xiamin Leng examines the impact of financial rewards and penalties on focus-and-filter strategies.

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Geckos know their own odor

Geckos can use their tongue to differentiate their own odor from that of other members of their species, as researchers from the University of Bern have shown in a new experimental study. The findings show that geckos are able to communicate socially, meaning that they are more intelligent than was previously assumed.

Self-recognition is the ability to detect stimuli which come from oneself. We as people, and also some animals, can identify ourselves visually when we look in the mirror. However, not all animals rely on their sense of sight, first and foremost. Geckos, and also other lizards and snakes, use their tongues to perceive chemicals, so-called pheromones, from other individuals. For instance, when climbing a wall, geckos pause every so often to dart their tongues around. This enables them to detect potential partners or rivals. But can geckos also detect their own odor and recognize themselves by smell?

In a study recently published in the journal Animal Cognition, researchers at the Institute of Ecology and Evolution of the University of Bern focused on whether Tokay geckos can detect skin chemicals that they themselves produce, and whether they can discriminate between these chemicals and those of other geckos of the same sex. The experiments confirmed that geckos are capable of this. During the tests, the animals were more interested in the skin chemicals of other geckos than in their own. This shows that geckos use pheromones for social communication.

Gecko and peppermint odor on cotton swabs

During the experiment, the researchers presented the geckos with various odors on cotton swabs. As well as their own odor, these were odors from other geckos, or control odors such as water and peppermint. When they reacted, the geckos showed two types of behavior: on one hand, they stuck out their tongues in the direction of the odor on the swab and, on the other hand, towards the surrounding area, their own home enclosure. The researchers interpreted this behavior as a sign that the geckos first perceive the odor on the swab, and then compare it with their own odor on the walls of the enclosure. "The geckos have to compare more frequently when confronted with the odor of another gecko, compared to their own odor. This indicates that they know their own odor," explains Birgit Szabo, lead author of the study from the Division of Behavioural Ecology at the University of Bern's Institute of Ecology and Evolution.

In an experiment, the team was also able to show that geckos detect and use the odors of their feces to distinguish themselves from others. Geckos also deposit pheromones on their excrement, for instance, to mark their territory. This is because, just like many mammals, geckos have preferred areas for defecation so that they can communicate their presence.

More social and intelligent than we thought

The findings of the study show that geckos can communicate socially by using chemicals from their skin and excrement, and that they use these chemicals to distinguish themselves from other geckos. "Lizards and reptiles are generally seen as unsocial primitive animals. We must recognize that reptiles are more social and intelligent than we thought," says Birgit Szabo.

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Just like humans, more intelligent jays have greater self-control

A study has found that Eurasian jays can pass a version of the 'marshmallow test' -- and those with the greatest self-control also score the highest on intelligence tests.

This is the first evidence of a link between self-control and intelligence in birds.

Self-control -- the ability to resist temptation in favour of a better but delayed reward -- is a vital skill that underpins effective decision-making and future planning.

Jays are members of the corvid family, often nicknamed the 'feathered apes' because they rival non-human primates in their cognitive abilities. Corvids hide, or 'cache', their food to save it for later. In other words, they need to delay immediate gratification to plan for future meals. The researchers think this may have driven the evolution of self-control in these birds.

Self-control has been previously shown to be linked to intelligence in humans, chimpanzees and -- in an earlier study by these researchers -- in cuttlefish. The greater the intelligence, the greater the self-control.

The new results show that the link between intelligence and self-control exists across distantly related animal groups, suggesting it has evolved independently several times.

Of all the corvids, jays in particular are vulnerable to having their caches stolen by other birds. Self-control also enables them to wait for the right moment to hide their food without being seen or heard.

The results are published today in the journal Philosophical Transactions of the Royal Society B.

To test the self-control of ten Eurasian jays, Garrulus glandarius, researchers designed an experiment inspired by the 1972 Stanford Marshmallow test -- in which children were offered a choice between one marshmallow immediately, or two if they waited for a period of time.

Instead of marshmallows, the jays were presented with mealworms, bread and cheese. Mealworms are a common favourite; bread and cheese come second but individuals vary in their preference for one over the other.

The birds had to choose between bread or cheese -- available immediately, and mealworm that they could see but could only get to after a delay, when a Perspex screen was raised. Could they delay immediate gratification and wait for their favourite food?

A range of delay times was tested, from five seconds to five and a half minutes, before the mealworm was made available if the bird had resisted the temptation to eat the bread or cheese.

All the birds in the experiment managed to wait for the worm, but some could wait much longer than others. Top of the class was 'JayLo', who ignored a piece of cheese and waited five and a half minutes for a mealworm. The worst performers, 'Dolci' and 'Homer', could only wait a maximum of 20 seconds.

"It's just mind-boggling that some jays can wait so long for their favourite food. In multiple trials, I sat there watching JayLo ignore a piece of cheese for over five minutes -- I was getting bored, but she was just patiently waiting for the worm," said Dr Alex Schnell at the University of Cambridge's Department of Psychology, first author of the report.

The jays looked away from the bread or cheese when it was presented to them, as if to distract themselves from temptation. Similar behaviour has been seen in chimpanzees and children.

The researchers also presented the jays with five cognitive tasks that are commonly used to measure general intelligence. The birds that performed better in these tasks also managed to wait longer for the mealworm reward. This suggests that self-control is linked with intelligence in jays.

"The birds' performance varied across individuals -- some did really well in all the tasks and others were mediocre. What was most interesting was that if a bird was good at one of the tasks, it was good at all of them -- which suggests that a general intelligence factor underlies their performance," said Schnell.

The jays also adjusted their self-control behaviour according to the circumstances: in another experiment where the worm was visible but always out of reach, the jays always ate the immediately available bread or cheese. And the length of time they were willing to wait for the worm fell if it was pitted against their second most preferred food as the immediate treat, compared to their third. This flexibility shows that jays only delay gratification when it is warranted.

Research by other scientists has found that children taking the Stanford marshmallow test vary greatly in their self-control, and this ability is linked to their general intelligence. Children that can resist temptation for longer also get higher scores in a range of academic tasks.

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Human brain cells in a dish learn to play Pong in real time

Human and mouse neurons in a dish learned to play the video game Pong, researchers report October 12 in the journal Neuron. The experiments are evidence that even brain cells in a dish can exhibit inherent intelligence, modifying their behavior over time.

"From worms to flies to humans, neurons are the starting block for generalized intelligence," says first author Brett Kagan (@ANeuroExplorer), chief scientific officer at Cortical Labs in Melbourne, Australia. "So, the question was, can we interact with neurons in a way to harness that inherent intelligence?"

To start, the researchers connected the neurons to a computer in such a way where the neurons received feedback on whether their in-game paddle was hitting the ball. They monitored the neuron's activity and responses to this feedback using electric probes that recorded "spikes" on a grid.

The spikes got stronger the more a neuron moved its paddle and hit the ball. When neurons missed, their playstyle was critiqued by a software program created by Cortical Labs. This demonstrated that the neurons could adapt activity to a changing environment, in a goal-oriented way, in real time.

"We chose Pong due to its simplicity and familiarity, but, also, it was one of the first games used in machine learning, so we wanted to recognize that," says Kagan, who worked with collaborators from 10 other institutions on the project.

"An unpredictable stimulus was applied to the cells, and the system as a whole would reorganize its activity to better play the game and to minimize having a random response," he says. "You can also think that just playing the game, hitting the ball and getting predictable stimulation, is inherently creating more predictable environments."

The theory behind this learning is rooted in the free-energy principle. Simply put, the brain adapts to its environment by changing either its world view or its actions to better fit the world around it.

Pong wasn't the only game the research team tested. "You know when the Google Chrome browser crashes and you get that dinosaur that you can make jump over obstacles (Project Bolan). We've done that and we've seen some nice preliminary results, but we still have more work to do building new environments for custom purposes," says Kagan.

Future directions of this work have potential in disease modeling, drug discoveries, and expanding the current understanding of how the brain works and how intelligence arises.

Read more at Science Daily

Reducing air pollution can support healthy brain development

A new study finds that having a portable air cleaner in the home can reduce the negative impacts of air pollution on brain development in children.

Simon Fraser University researchers collaborated with U.S. and Mongolian scientists to study the benefits of using air filters to reduce exposure to air pollution during pregnancy, and assessed the impact on children's intelligence.

The researchers note that their randomized controlled trial is the first study of its kind to document the impacts of air pollution reduction on cognition in children.

Beginning in 2014, the team recruited 540 pregnant women in Ulaanbaatar, Mongolia to participate in the Ulaanbaatar Gestation and Air Pollution Research (UGAAR) study. Ulaanbaatar has some of the worst air quality in the world, well exceeding guidelines set by the World Health Organization (WHO).

The women were less than 18 weeks into their pregnancies and non-smokers who had not previously used air filtering devices in their homes. They were randomly assigned to either the control or intervention group. The intervention group was provided with one or two HEPA filter air cleaners and encouraged to run the air cleaners continuously for the duration of their pregnancies. The air cleaners were removed from the home once the child was born.

The researchers later measured the children's full-scale intelligence quotient (FSIQ) at four years of age using the Weschler Preschool and Primary Scale of Intelligence.

They found that the children born to mothers who had used the air cleaners had an average FSIQ that was 2.8-points higher than the group that did not use an air cleaner during pregnancy.

"These results, combined with evidence from previous studies, strongly implicate air pollution as a threat to brain development," says Ryan Allen, professor of environmental health in SFU's Faculty of Health Sciences. "But the good news is that reducing exposure had clear benefits."

Children in the intervention group also had significantly greater average verbal comprehension index scores, which is consistent with results from previous observational studies. The research suggests that a child's verbal skills may be particularly sensitive to air pollution exposure.

More than 90 per cent of the world's population breathes air with particulate matter concentrations above the WHO guidelines. The researchers suggest the population-level impact of air pollution on brain development could be substantive even if the individual-level effects are modest.

Their study results indicate that reducing exposure to air pollution during pregnancy could improve children's cognitive development around the world.

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Video games can help boost children's intelligence

Researchers at Karolinska Institutet in Sweden have studied how the screen habits of US children correlates with how their cognitive abilities develop over time. They found that the children who spent an above-average time playing video games increased their intelligence more than the average, while TV watching or social media had neither a positive nor a negative effect. The results are published in the journal Scientific Reports.

Children are spending more and more time in front of screens. How this affects their health and whether it has a positive or negative impact on their cognitive abilities are hotly debated. For this present study, researchers at Karolinska Institutet and Vrije Universiteit Amsterdam specifically studied the link between screen habits and intelligence over time.

Over 9,000 boys and girls in the USA participated in the study. At the age of nine or ten, the children performed a battery of psychological tests to gauge their general cognitive abilities (intelligence). The children and their parents were also asked about how much time the children spent watching TV and videos, playing video games and engaging with social media.

Followed up after two years

Just over 5,000 of the children were followed up after two years, at which point they were asked to repeat the psychological tests. This enabled the researchers to study how the children's performance on the tests varied from the one testing session to the other, and to control for individual differences in the first test. They also controlled for genetic differences that could affect intelligence and differences that could be related to the parents' educational background and income.

On average, the children spent 2.5 hours a day watching TV, half an hour on social media and 1 hour playing video games. The results showed that those who played more games than the average increased their intelligence between the two measurements by approximately 2.5 IQ points more than the average. No significant effect was observed, positive or negative, of TV-watching or social media.

"We didn't examine the effects of screen behaviour on physical activity, sleep, wellbeing or school performance, so we can't say anything about that," says Torkel Klingberg, professor of cognitive neuroscience at the Department of Neuroscience, Karolinska Institutet. "But our results support the claim that screen time generally doesn't impair children's cognitive abilities, and that playing video games can actually help boost intelligence. This is consistent with several experimental studies of video-game playing."

Intelligence is not constant

The results are also in line with recent research showing that intelligence is not a constant, but a quality that is influenced by environmental factors.

"We'll now be studying the effects of other environmental factors and how the cognitive effects relate to childhood brain development," says Torkel Klingberg.

One limitation of the study is that it only covered US children and did not differentiate between different types of video games, which makes the results difficult to transfer to children in other countries with other gaming habits. There was also a risk of reporting error since screen time and habits were self-rated.

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Rare discovery: How a gene mutation causes higher intelligence

Synapses are the contact points in the brain via which nerve cells 'talk' to each other. Disturbances in this communication lead to diseases of the nervous system, since altered synaptic proteins, for example, can impair this complex molecular mechanism. This can result in mild symptoms, but also very severe disabilities in those affected.

The interest of the two neurobiologists Professor Tobias Langenhan and Professor Manfred Heckmann, from Leipzig and Würzburg respectively, was aroused when they read in a scientific publication about a mutation that damages a synaptic protein. At first, the affected patients attracted scientists' attention because the mutation caused them to go blind. However, doctors then noticed that the patients were also of above-average intelligence. "It's very rare for a mutation to lead to improvement rather than loss of function," says Langenhan, professor and holder of a chair at the Rudolf Schönheimer Institute of Biochemistry at the Faculty of Medicine.

The two neurobiologists from Leipzig and Würzburg have been using fruit flies to analyse synaptic functions for many years. "Our research project was designed to insert the patients' mutation into the corresponding gene in the fly and use techniques such as electrophysiology to test what then happens to the synapses. It was our assumption that the mutation makes patients so clever because it improves communication between the neurons which involve the injured protein," explains Langenhan. "Of course, you can't conduct these measurements on the synapses in the brains of human patients. You have to use animal models for that."

75 per cent of genes that cause diseases in humans also exist in fruit flies

First, the scientists, together with researchers from Oxford, showed that the fly protein called RIM looks molecularly identical to that of humans. This was essential in order to be able to study the changes in the human brain in the fly. In the next step, the neurobiologists inserted mutations into the fly genome that looked exactly as they did in the diseased people. They then took electrophysiological measurements of synaptic activity. "We actually observed that the animals with the mutation showed a much increased transmission of information at the synapses. This amazing effect on the fly synapses is probably found in the same or a similar way in human patients, and could explain their increased cognitive performance, but also their blindness," concludes Professor Langenhan.

The scientists also found out how the increased transmission at the synapses occurs: the molecular components in the transmitting nerve cell that trigger the synaptic impulses move closer together as a result of the mutation effect and lead to increased release of neurotransmitters. A novel method, super-resolution microscopy, was one of the techniques used in the study. "This gives us a tool to look at and even count individual molecules and confirms that the molecules in the firing cell are closer together than they normally are," says Professor Langenhan, who was also assisted in the study by Professor Hartmut Schmidt's research group from the Carl Ludwig Institute in Leipzig.

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Lead exposure in last century shrank IQ scores of half of Americans, study finds

In 1923, lead was first added to gasoline to help keep car engines healthy. However, automotive health came at the great expense of our own health and well-being.

A new study calculates that exposure to car exhaust from leaded gas during childhood stole a collective 824 million IQ points from more than 170 million Americans alive today, about half the population of the United States.

The findings, from Aaron Reuben, a PhD candidate in clinical psychology at Duke University, and colleagues at Florida State University, suggest that Americans born before 1996 may now be at greater risk for lead-related health problems, such as faster aging of the brain. Leaded gas for cars was banned in the U.S. in 1996, but the researchers say that anyone born before the end of that era, and especially those at the peak of its use in the 1960s and 1970s, had concerningly high lead exposures as children.

The team's paper appeared the week of March 7 in the journal Proceedings of the National Academy of Sciences.

Lead is neurotoxic and can erode brain cells after it enters the body. As such, there is no safe level of exposure at any point in life, health experts say. Young children are especially vulnerable to lead's ability to impair brain development and lower cognitive ability. Unfortunately, no matter what age, our brains are ill-equipped for keeping it at bay.

"Lead is able to reach the bloodstream once it's inhaled as dust, or ingested, or consumed in water," Reuben said. "In the bloodstream, it's able to pass into the brain through the blood-brain barrier, which is quite good at keeping a lot of toxicants and pathogens out of the brain, but not all of them."

One major way lead used to invade bloodstreams was through automotive exhaust.

To answer the complex question of how leaded gas use for more than 70 years may have left a permanent mark on human health, Reuben and his co-authors Michael McFarland and Mathew Hauer, both professors of sociology at Florida State University, opted for a fairly simple strategy.

Using publicly available data on U.S. childhood blood-lead levels, leaded-gas use, and population statistics, they determined the likely lifelong burden of lead exposure carried by every American alive in 2015. From this data, they estimated lead's assault on our intelligence by calculating IQ points lost from leaded gas exposure as a proxy for its harmful impact on public health.

The researchers were stunned by the results.

"I frankly was shocked," McFarland said. "And when I look at the numbers, I'm still shocked even though I'm prepared for it."

As of 2015, more than 170 million Americans (more than half of the U.S. population) had clinically concerning levels of lead in their blood when they were children, likely resulting in lower IQs and putting them at higher risk for other long-term health impairments, such as reduced brain size, greater likelihood of mental illness, and increased cardiovascular disease in adulthood.

Leaded gasoline consumption rose rapidly in the early 1960s and peaked in the 1970s. As a result, Reuben and his colleagues found that essentially everyone born during those two decades are all but guaranteed to have been exposed to pernicious levels of lead from car exhaust.

Even more startling was lead's toll on intelligence: childhood lead exposure may have blunted America's cumulative IQ score by an estimated 824 million points -- nearly three points per person on average. The researchers calculated that at its worst, people born in the mid-to-late 1960s may have lost up to six IQ points, and children registering the highest levels of lead in their blood, eight times the current minimum level to initiate clinical concern, fared even worse, potentially losing more than seven IQ points on average.

Dropping a few IQ points may seem negligible, but the authors note that these changes are dramatic enough to potentially shift people with below-average cognitive ability (IQ score less than 85) to being classified as having an intellectual disability (IQ score below 70).

Moving forward, McFarland is analyzing the racial disparities of childhood lead exposure, hoping to highlight the health inequities suffered by Black children, who were exposed more often to lead and in greater quantities than white children.

Reuben's next step will be to examine the long-term consequences of past lead exposure on brain health in old age, based on previous findings that adults with high childhood lead exposure may experience accelerated brain aging.

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High daily screen time linked to cognitive, behavioral problems in children born extremely preterm

Among 6- and 7-year-olds who were born extremely preterm -- before the 28th week of pregnancy -- those who had more than two hours of screen time a day were more likely to have deficits in overall IQ, executive functioning (problem solving skills), impulse control and attention, according to a study funded by the National Institutes of Health. Similarly, those who had a television or computer in their bedrooms were more likely to have problems with impulse control and paying attention. The findings suggest that high amounts of screen time may exacerbate the cognitive deficits and behavioral problems common to children born extremely preterm.

The study was conducted by Betty R. Vohr, M.D., and colleagues. It appears in JAMA Pediatrics. Funding was provided by NIH's Eunice Kennedy Shriver National Institute of Child Health and Human Development; National Heart, Lung, and Blood Institute; and National Center for Advancing Translational Sciences.

Previous studies have linked high amounts of screen time among children born full-term to language and developmental, behavioral and other problems. In the current study, researchers analyzed data from a study of children born at 28 weeks or earlier. Of 414 children, 238 had more than two hours of screen time per day and 266 had a television or computer in their bedrooms. Compared to children with less screen time per day, those with high amounts of screen time scored an average deficit of nearly 8 points on global executive function percentile scores, roughly 0.8 points lower on impulse control (inhibition) and more than 3 points higher on inattention. Children with a television or computer in their bedrooms also scored lower on measures of inhibition, hyperactivity and impulsivity.

The authors concluded that the findings support the need for physicians to discuss the potential effects of screen time with families of children born extremely preterm.

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Epigenetic mechanism can explain how chemicals in plastic may cause lower IQ levels

The chemical bisphenol F (found in plastics) can induce changes in a gene that is vital for neurological development. This discovery was made by researchers at the universities of Uppsala and Karlstad, Sweden. The mechanism could explain why exposure to this chemical during the fetal stage may be connected with a lower IQ at seven years of age -- an association previously seen by the same research group. The study is published in the scientific journal Environment International.

"We've previously shown that bisphenol F (BPF for short) may be connected with children's cognitive development. However, with this study, we can now begin to understand which biological mechanisms may explain such a link, which is unique for an epidemiological study." The speaker is Carl Gustaf Bornehag, Professor and head of Public Health Sciences at Karlstad University. He is the project manager of the Swedish Environmental Longitudinal Mother and Child, Asthma and Allergy (SELMA) study, from which the data were taken.

External factors can cause changes in gene activity through an "epigenetic" mechanism. This means that individual genes are modified by means of "methylation." Increased methylation in a DNA segment makes it more difficult for the cellular machinery to read that specific part. As a result, expression of methylated genes is often impaired.

The scientists measured BPF levels in urine from pregnant women in the first trimester and subsequently monitored their children after birth. DNA methylation was measured in the children at age seven, and their cognitive ability was investigated. Since the fetus comes into contact with the mother's blood via the placenta, it is also exposed to substances in the mother's body.

The analyses demonstrated that in fetuses exposed to higher levels of BPF, methylation increases in a specific part of the GRIN2B gene, which has a key neurological role. Further, higher methylation was associated with lower IQ in the children. However, the study also found that there appears to be a sex difference in these children's susceptibility to BPF. The epigenetic link between BPF and cognition was observed only in boys.

"The fact that we've been able to identify DNA methylation as a potential mechanism behind BPF's effect on IQ adds an important piece of evidence in work to understand how environmental chemicals affect us on a molecular level," says Elin Engdahl, a researcher in environmental toxicology at Uppsala University and the article's lead author.

Read more at Science Daily

Human intelligence just got less mysterious

 Neuroscience experts from the University of Leicester have released research that breaks with the past fifty years of neuroscientific opinion, arguing that the way we store memories is key to making human intelligence superior to that of animals.

It has previously been thought and copiously published that it is 'pattern separation' in the hippocampus, an area of the brain critical for memory, that enables memories to be stored by separate groups of neurons, so that memories don't get mixed up.

Now, after fifteen years of research, Leicester University's Director of Systems Neuroscience believes that in fact the opposite to pattern separation is present in the human hippocampus. He argues that, contrary to what has been described in animals, the same group of neurons store all memories. The consequences of this are far reaching, as such neuronal representation, devoid of specific contextual details, explains the abstract thinking that characterizes human intelligence.

Leicester University's Director of Systems Neuroscience Professor Rodrigo Quian Quiroga explains,

"In contrast to what everybody expects, when recording the activity of individual neurons we have found that there is an alternative model to pattern separation storing our memories.

"Pattern separation is a basic principle of neuronal coding that precludes memory interference in the hippocampus. Its existence is supported by numerous theoretical, computational and experimental findings in different animal species but these findings have never been directly replicated in humans. Previous human studies have been mostly obtained using Functional Magnetic Resource Imagining (fMRI), which doesn't allow recording the activity of individual neurons. Shockingly, when we directly recorded the activity of individual neurons, we found something completely different to what has been described in other animals. This could well be a cornerstone of human's intelligence."

The study, 'No pattern sepaeration in the human hippocampus', argues that the lack of pattern separation in memory coding is a key difference compared to other species, which has profound implications that could explain cognitive abilities uniquely developed in humans, such as our power of generalization and of creative thought.

Read more at Science Daily

Vitamin D levels during pregnancy linked with child IQ

 Vitamin D is a critical nutrient and has many important functions in the body. A mother's vitamin D supply is passed to her baby in utero and helps regulate processes including brain development. A study published today in The Journal of Nutrition showed that mothers' vitamin D levels during pregnancy were associated with their children's IQ, suggesting that higher vitamin D levels in pregnancy may lead to greater childhood IQ scores. The study also identified significantly lower levels of vitamin D levels among Black pregnant women.

Melissa Melough, the lead author of the study and research scientist in the Department of Child Health, Behavior, and Development at Seattle Children's Research Institute, says vitamin D deficiency is common among the general population as well as pregnant women, but notes that Black women are at greater risk. Melough says she hopes the study will help health care providers address disparities among women of color and those who are at higher risk for vitamin D deficiency.

"Melanin pigment protects the skin against sun damage, but by blocking UV rays, melanin also reduces vitamin D production in the skin. Because of this, we weren't surprised to see high rates of vitamin D deficiency among Black pregnant women in our study. Even though many pregnant women take a prenatal vitamin, this may not correct an existing vitamin D deficiency," Melough said. "I hope our work brings greater awareness to this problem, shows the long-lasting implications of prenatal vitamin D for the child and their neurocognitive development, and highlights that there are certain groups providers should be paying closer attention to. Wide-spread testing of vitamin D levels is not generally recommended, but I think health care providers should be looking out for those who are at higher risk, including Black women."

Addressing disparities

According to Melough, as many as 80% of Black pregnant women in the U.S. may be deficient in vitamin D. Of the women who participated in the study, approximately 46% of the mothers were deficient in vitamin D during their pregnancy, and vitamin D levels were lower among Black women compared to White women.

Melough and her co-authors used data from a cohort in Tennessee called the Conditions Affecting Neurocognitive Development and Learning in Early Childhood (CANDLE) study. CANDLE researchers recruited pregnant women to join the study starting in 2006 and collected information over time about their children's health and development.

After controlling for several other factors related to IQ, higher vitamin D levels in pregnancy were associated with higher IQ in children ages 4 to 6 years old. Although observational studies like this one cannot prove causation, Melough believes her findings have important implications and warrant further research.

Vitamin D deficiency

"Vitamin D deficiency is quite prevalent," Melough said. "The good news is there is a relatively easy solution. It can be difficult to get adequate vitamin D through diet, and not everyone can make up for this gap through sun exposure, so a good solution is to take a supplement."

The recommended daily intake of vitamin D is 600 international units (IU). On average, Americans consume less than 200 IU in their diet, and so if people aren't making up that gap through sun exposure or supplementation, Melough says people will probably become deficient. Foods that contain higher levels of vitamin D include fatty fish, eggs and fortified sources like cow's milk and breakfast cereals. However, Melough notes that vitamin D is one of the most difficult nutrients to get in adequate amounts from our diets.

Additional research is needed to determine the optimal levels of vitamin D in pregnancy, but Melough hopes this study will help to develop nutritional recommendations for pregnant women. Especially among Black women and those at high risk for vitamin D deficiency, nutritional supplementation and screening may be an impactful strategy for reducing health disparities.

Read more at Science Daily

Primate brain size does not predict their intelligence

 Chimpanzees, gorillas and orangutans are our closest relatives, and like us they have relatively large brains and they are very intelligent. But do animals with larger brains really perform better in cognitive tests? A research team from the German Primate Center (DPZ) -- Leibniz Institute for Primate Research in Göttingen has for the first time systematically investigated the cognitive abilities of lemurs, which have relatively small brains compared to other primates. Conducting systematic tests with identical methods revealed that cognitive abilities of lemurs hardly differ from those of monkeys and great apes. Instead, this study revealed that the relationship between brain size and cognitive abilities cannot be generalized and it provides new insights into the evolution of cognitive abilities in primates.

Humans and non-human primates are among the most intelligent living beings. Their brain size may underly their intelligence as primates have relatively large brains in relation to their body size. For example, it is assumed that larger brains enable faster learning and better memory capacities. Within primates, however, species can differ up to 200-fold in brain size. A team of researchers from the German Primate Center (DPZ) has now investigated whether the cognitive performances of lemurs with their relatively small brains differ from those of other primates.

Using a comprehensive standardized test series of cognitive experiments, the so-called "Primate Cognition Test Battery" (PCTB), small children, great apes as well as baboons and macaques have already been tested for their cognitive abilities in the physical and social domain. Cognitive skills in the physical domain include the understanding of spatial, numerical and causal relationships between inanimate objects, while cognitive skills in the social domain deal with intentional actions, perceptions and the understanding of the knowledge of other living beings. Initial studies have shown that children possess a better social intelligence than non-human primates. In the physical domain, however, the species hardly differed even though they show great variation in their relative brain sizes.

For the first time, researchers of the "Behavioral Ecology and Sociobiology Unit" of the DPZ have now tested three lemur species with the PCTB. Lemurs are the most basal living primates and represent the evolutionary link between primates and other mammals, which is why they serve as a living model of primates' origin of cognitive abilities. The study examined ring-tailed lemurs, black-and-white ruffed lemurs and grey mouse lemurs, which differ in their social system, diet and brain size, not only among each other, but also compared to the previously tested Old World monkeys and great apes.

The results of the new study show that despite their smaller brains lemurs' average cognitive performance in the tests of the PCTB was not fundamentally different from the performances of the other primate species. This is even true for mouse lemurs, which have brains about 200 times smaller than those of chimpanzees and orangutans. Only in tests examining spatial reasoning primate species with larger brains performed better. However, no systematic differences in species performances were neither found for the understanding of causal and numerical relationships nor in tests of the social domain. Neither diet, nor social system or brain size could explain the results from the PCTB experiments. "With our study we show that cognitive abilities cannot be generalized, but that species instead differ in domain-specific cognitive skills," says Claudia Fichtel, one of the two first authors of the study funded by the German Research Foundation. "Accordingly, the relationship between brain size and cognitive abilities cannot be generalized."

Read more at Science Daily

New light shed on intelligent life existing across the galaxy

One of the biggest and longest-standing questions in the history of human thought is whether there are other intelligent life forms within our Universe. Obtaining good estimates of the number of possible extraterrestrial civilizations has however been very challenging.

A new study led by the University of Nottingham and published today in The Astrophysical Journal has taken a new approach to this problem. Using the assumption that intelligent life forms on other planets in a similar way as it does on Earth, researchers have obtained an estimate for the number of intelligent communicating civilizations within our own galaxy -the Milky Way. They calculate that there could be over 30 active communicating intelligent civilizations in our home Galaxy.

Professor of Astrophysics at the University of Nottingham, Christopher Conselice who led the research, explains: "There should be at least a few dozen active civilizations in our Galaxy under the assumption that it takes 5 billion years for intelligent life to form on other planets, as on Earth." Conselice also explains that, "The idea is looking at evolution, but on a cosmic scale. We call this calculation the Astrobiological Copernican Limit."

First author Tom Westby explains: "The classic method for estimating the number of intelligent civilizations relies on making guesses of values relating to life, whereby opinions about such matters vary quite substantially. Our new study simplifies these assumptions using new data, giving us a solid estimate of the number of civilizations in our Galaxy.

The two Astrobiological Copernican limits are that intelligent life forms in less than 5 billion years, or after about 5 billion years -- similar to on Earth where a communicating civilization formed after 4.5 billion years. In the strong criteria, whereby a metal content equal to that of the Sun is needed (the Sun is relatively speaking quite metal rich), we calculate that there should be around 36 active civilizations in our Galaxy."

The research shows that the number of civilizations depends strongly on how long they are actively sending out signals of their existence into space, such as radio transmissions from satellites, television, etc. If other technological civilizations last as long as ours which is currently 100 years old, then there will be about 36 ongoing intelligent technical civilizations throughout our Galaxy.

However, the average distance to these civilizations would be 17,000 light-years away, making detection and communication very difficult with our present technology. It is also possible that we are the only civilization within our Galaxy unless the survival times of civilizations like our own are long.

Professor Conselice continues: "Our new research suggests that searches for extraterrestrial intelligent civilizations not only reveals the existence of how life forms, but also gives us clues for how long our own civilization will last. If we find that intelligent life is common then this would reveal that our civilization could exist for much longer than a few hundred years, alternatively if we find that there are no active civilizations in our Galaxy it is a bad sign for our own long-term existence. By searching for extraterrestrial intelligent life -- even if we find nothing -- we are discovering our own future and fate."

From Science Daily

How cognitive intelligence is a whole brain phenomenon

An international collaborative study led by researchers from the NUI Galway provides findings on the neural basis of intelligence, otherwise known as general cognitive ability (IQ).

This new research uses an imaging technique called diffusion tensor imaging (DTI) to provide an insight into how small variations in this wiring system is associated with differences in IQ in both the general population and how disorders such as schizophrenia manifest.

Over 40 scientists from around the world were involved in analysing brain MRI scans and measures of cognitive function of 1,717 participants, with both healthy functions and patients with schizophrenia. This resulted in a new method to harmonise data collection and analysis as part of the Enhancing Neuroimaging Genetics through Meta-Analysis project (ENIGMA), Schizophrenia Working Group. The study, published in The American Journal of Psychiatry, was led by Dr Laurena Holleran, Lecturer in Clinical Neuroscience and Professor Gary Donohoe, Established Professor at NUI Galway's School of Psychology and Centre for Neuroimaging Cognition and Genomics.

Commenting on the findings, lead author Dr Laurena Holleran, stated that: "To date, this is the largest meta-analysis study of brain structure and cognitive function in schizophrenia. Understanding the neural basis of cognitive function is essential so that effective therapies that address difficulties associated with disorders like schizophrenia, which aren't targeted by current treatments. This is important because cognitive deficits associated with the disorder strongly predict social and functional outcomes, such as employment or social relationships.

"Previous literature suggested that general intelligence relies on specific grey matter areas of the brain, including temporal, parietal and frontal regions. However, the results from this study indicate that efficient connection pathways across the entire brain provide a neural network that supports general cognitive function."

According to the study's senior author Professor Gary Donohoe: "These results advance our knowledge in a number of ways. Firstly, we have demonstrated that the relationship between brain structure and intelligence not only involves grey matter, but also white matter -- the brain's wiring system. Secondly, it's not just one part of this wiring system that is important for intelligence, but rather the wiring system as a whole. And finally, the relationship between intelligence and the brain's wiring system is basically the same in patients with schizophrenia and healthy people, in that the lack of pattern explains their cognitive abilities. This suggests that cognitive function in patients is the same as the general population, at least as far as white matter is concerned."

From Science Daily

Breakthrough Listen releases 2 petabytes of data from SETI survey of Milky Way

The Breakthrough Listen Initiative today (Friday, Feb. 14) released data from the most comprehensive survey yet of radio emissions from the plane of the Milky Way Galaxy and the region around its central black hole, and it is inviting the public to search the data for signals from intelligent civilizations.

At a media briefing today in Seattle as part of the annual meeting of the American Association for the Advancement of Science (AAAS), Breakthrough Listen principal investigator Andrew Siemion of the University of California, Berkeley, announced the release of nearly 2 petabytes of data, the second data dump from the four-year old search for extraterrestrial intelligence (SETI). A petabyte of radio and optical telescope data was released last June, the largest release of SETI data in the history of the field.

The data, most of it fresh from the telescope prior to detailed study from astronomers, comes from a survey of the radio spectrum between 1 and 12 gigahertz (GHz). About half of the data comes via the Parkes radio telescope in New South Wales, Australia, which, because of its location in the Southern Hemisphere, is perfectly situated and instrumented to scan the entire galactic disk and galactic center. The telescope is part of the Australia Telescope National Facility, owned and managed by the country's national science agency, CSIRO.

The remainder of the data was recorded by the Green Bank Observatory in West Virginia, the world's largest steerable radio dish, and an optical telescope called the Automated Planet Finder, built and operated by UC Berkeley and located at Lick Observatory outside San Jose, California.

"Since Breakthrough Listen's initial data release last year, we have doubled what is available to the public," said Breakthrough Listen's lead system administrator, Matt Lebofsky. "It is our hope that these data sets will reveal something new and interesting, be it other intelligent life in the universe or an as-yet-undiscovered natural astronomical phenomenon."

The National Radio Astronomy Observatory (NRAO) and the privately-funded SETI Institute in Mountain View, California, also announced today an agreement to collaborate on new systems to add SETI capabilities to radio telescopes operated by NRAO. The first project will develop a system to piggyback on the National Science Foundation's Karl G. Jansky Very Large Array (VLA) in New Mexico and provide data to state-of-the-art digital backend equipment built by the SETI Institute.

"The SETI Institute will develop and install an interface on the VLA, permitting unprecedented access to the rich data stream continuously produced by the telescope as it scans the sky," said Siemion, who, in addition to his UC Berkeley position, is the Bernard M. Oliver Chair for SETI at the SETI Institute. "This interface will allow us to conduct a powerful, wide-area SETI survey that will be vastly more complete than any previous such search."

"As the VLA conducts its usual scientific observations, this new system will allow for an additional and important use for the data we're already collecting," said NRAO Director Tony Beasley. "Determining whether we are alone in the universe as technologically capable life is among the most compelling questions in science, and NRAO telescopes can play a major role in answering it."

"For the whole of human history, we had a limited amount of data to search for life beyond Earth. So, all we could do was speculate. Now, as we are getting a lot of data, we can do real science and, with making this data available to general public, so can anyone who wants to know the answer to this deep question," said Yuri Milner, the founder of Breakthrough Listen.

Earth transit zone survey

In releasing the new radio and optical data, Siemion highlighted a new analysis of a small subset of the data: radio emissions from 20 nearby stars that are aligned with the plane of Earth's orbit such that an advanced civilization around those stars could see Earth pass in front of the sun (a "transit" like those focused on by NASA's Kepler space telescope). Conducted by the Green Bank Telescope, the Earth transit zone survey observed in the radio frequency range between 4 and 8 gigahertz, the so-called C-band. The data were then analyzed by former UC Berkeley undergraduate Sofia Sheikh, now a graduate student at Pennsylvania State University, who looked for bright emissions at a single radio wavelength or a narrow band around a single wavelength. She has submitted the paper to the Astrophysical Journal.

"This is a unique geometry," Sheikh said. "It is how we discovered other exoplanets, so it kind of makes sense to extrapolate and say that that might be how other intelligent species find planets, as well. This region has been talked about before, but there has never been a targeted search of that region of the sky."

While Sheikh and her team found no technosignatures of civilization, the analysis and other detailed studies the Breakthrough Listen group has conducted are gradually putting limits on the location and capabilities of advanced civilizations that may exist in our galaxy.

"We didn't find any aliens, but we are setting very rigorous limits on the presence of a technologically capable species, with data for the first time in the part of the radio spectrum between 4 and 8 gigahertz," Siemion said. "These results put another rung on the ladder for the next person who comes along and wants to improve on the experiment."

Sheikh noted that her mentor, Jason Wright at Penn State, estimated that if the world's oceans represented every place and wavelength we could search for intelligent signals, we have, to date, explored only a hot tub's worth of it.

"My search was sensitive enough to see a transmitter basically the same as the strongest transmitters we have on Earth, because I looked at nearby targets on purpose," Sheikh said. "So, we know that there isn't anything as strong as our Arecibo telescope beaming something at us. Even though this is a very small project, we are starting to get at new frequencies and new areas of the sky."

Beacons in the galactic center?

The so-far unanalyzed observations from the galactic disk and galactic center survey were a priority for Breakthrough Listen because of the higher likelihood of observing an artificial signal from that region of dense stars. If artificial transmitters are not common in the galaxy, then searching for a strong transmitter among the billions of stars in the disk of our galaxy is the best strategy, Simeon said.

On the other hand, putting a powerful, intergalactic transmitter in the core of our galaxy, perhaps powered by the 4 million-solar-mass black hole there, might not be beyond the capabilities of a very advanced civilization. Galactic centers may be so-called Schelling points: likely places for civilizations to meet up or place beacons, given that they cannot communicate among themselves to agree on a location.

"The galactic center is the subject of a very specific and concerted campaign with all of our facilities because we are in unanimous agreement that that region is the most interesting part of the Milky Way galaxy," Siemion said. "If an advanced civilization anywhere in the Milky Way wanted to put a beacon somewhere, getting back to the Schelling point idea, the galactic center would be a good place to do it. It is extraordinarily energetic, so one could imagine that if an advanced civilization wanted to harness a lot of energy, they might somehow use the supermassive black hole that is at the center of the Milky Way galaxy."

Visit from an interstellar comet

Breakthrough Listen also released observations of the interstellar comet 2I/Borisov, which had a close encounter with the sun in December and is now on its way out of the solar system. The group had earlier scanned the interstellar rock 'Oumuamua, which passed through the center of our solar system in 2017. Neither exhibited technosignatures.

"If interstellar travel is possible, which we don't know, and if other civilizations are out there, which we don't know, and if they are motivated to build an interstellar probe, then some fraction greater than zero of the objects that are out there are artificial interstellar devices," said Steve Croft, a research astronomer with the Berkeley SETI Research Center and Breakthrough Listen. "Just as we do with our measurements of transmitters on extrasolar planets, we want to put a limit on what that number is."

Regardless of the kind of SETI search, Siemion said, Breakthrough Listen looks for electromagnetic radiation that is consistent with a signal that we know technology produces, or some anticipated signal that technology could produce, and inconsistent with the background noise from natural astrophysical events. This also requires eliminating signals from cellphones, satellites, GPS, internet, Wi-fi and myriad other human sources.

In Sheikh's case, she turned the Green Bank telescope on each star for five minutes, pointed away for another five minutes and repeated that twice more. She then threw out any signal that didn't disappear when the telescope pointed away from the star. Ultimately, she whittled an initial 1 million radio spikes down to a couple hundred, which she was able to eliminate as Earth-based human interference. The last four unexplained signals turned out to be from passing satellites.

Siemion emphasized that the Breakthrough Listen team intends to analyze all the data released to date and to do it systematically and often.

Read more at Science Daily

High IQs won't be enough to prevent ecological disasters

High IQs aren't going to be enough to stop an ecological disaster. It's going to take social intelligence, too.

That's the conclusion of a new study co-authored by a University of Central Florida researcher and published Wednesday in the journal Nature Communications.

The findings could help identify why some groups better manage shared resources, such as water or fisheries, than others. And as Earth's population is growing at a rate that is putting a strain on resources, finding ways to better manage them is critical.

"Especially in the case of common property, there is often an inbuilt tension between what is good for the individual and what is good for the group," says Jacopo Baggio, an assistant professor in UCF's Department of Political Science and lead author of the study.

"Individuals often have different cognitive abilities," Baggio says. "For example, individuals with high general intelligence will be more able to discern patterns and dynamics of resources, and individuals with high social intelligence communicate more effectively and understand the mental state of others."

Using a digital game to simulate a virtual ecosystem, the researchers found that when teams of people with high general intelligence, but low social intelligence faced a situation where resources became scarce, those teams depleted resources faster, harvested less potential resources and pushed the ecosystem to its limits.

But when both general and social intelligence were high, teams harvested a greater percentage of potential resources and kept the ecosystem from collapsing.

"It's a way to really start to understand how individuals and groups interact and what type of individuals are more prone or less prone to favor group benefits over individual costs," Baggio says.

General intelligence helped people figure out the rules of the game and how the resources, in this case digital tokens, regenerated, while social intelligence helped people cooperate to optimize performance, says Thomas Coyle, co-author of the study and professor of psychology at the University of Texas at San Antonio.

"In theory, people with higher levels of social intelligence are more effective in reducing conflict among group members and in getting people to work toward common goals," Coyle says. "Such 'people' skills are important for managing shared resources."

The work points to a need for education in diverse types of intelligence, says Jacob Freeman, an assistant professor of anthropology at Utah State University and study co-author.

"It suggests that our education systems should focus on cultivating both general and social intelligence to better equip groups to deal with complex, social-ecological challenges," Freeman says.

Coyle says researchers are still exploring ways to improve social intelligence.

For the study, the researchers used a digital game where people collected virtual tokens in exchange for actual money. Participants were 216 undergraduates from two large universities in the Western United States. They were randomly placed into one of two experimental conditions: either a game where the conditions began improving and tokens continued to be replenished, or one where conditions began deteriorating and tokens did not regenerate fast enough.

Read more at Science Daily

Smarter brains run on sparsely connected neurons

Erhan Genc investigates how intelligence is reflected in brain structures.

The more intelligent a person, the fewer connections there are between the neurons in his cerebral cortex. This is the result of a study conducted by neuroscientists working with Dr Erhan Genç and Christoph Fraenz at Ruhr-Universität Bochum; the study was performed using a specific neuroimaging technique that provides insights into the wiring of the brain on a microstructural level.

Together with colleagues from the University of New Mexico in Albuquerque, Humboldt University of Berlin and the Lovelace Biomedical and Environmental Research Institute in Albuquerque, the team from the biopsychology research unit in Bochum published their report in the journal Nature Communications on May 15, 2018.

Intelligence is determined by the number of dendrites

The researchers analysed the brains of 259 men and women using neurite orientation dispersion and density imaging. This method enabled them to measure the amount of dendrites in the cerebral cortex, i.e. extensions of nerve cells that are used by the cells to communicate with each other. In addition, all participants completed an IQ test. Subsequently, the researchers associated the gathered data with each other and found out: the more intelligent a person, the fewer dendrites there are in their cerebral cortex.

Using an independent, publicly accessible database, which had been compiled for the Human Connectome Project, the team confirmed these results in a second sample of around 500 individuals.

Previously conflicting results are thus explained

The new findings provide an explanation of conflicting results gathered in intelligence research to date. For one, it had been previously ascertained that intelligent people tend to have larger brains. "The assumption has been that larger brains contain more neurons and, consequently, possess more computational power," says Erhan Genç. However, other studies had shown that -- despite their comparatively high number of neurons -- the brains of intelligent people demonstrated less neuronal activity during an IQ test than the brains of less intelligent individuals.

"Intelligent brains possess lean, yet efficient neuronal connections," concludes Erhan Genç. "Thus, they boast high mental performance at low neuronal activity."

From Science Daily