Chapter 18. Attention and Higher Cognition

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By Carl Zimmer On a muggy June night in Greenwich Village, more than 800 neuroscientists, philosophers and curious members of the public packed into an auditorium. They came for the first results of an ambitious investigation into a profound question: What is consciousness? To kick things off, two friends — David Chalmers, a philosopher, and Christof Koch, a neuroscientist — took the stage to recall an old bet. In June 1998, they had gone to a conference in Bremen, Germany, and ended up talking late one night at a local bar about the nature of consciousness. For years, Dr. Koch had collaborated with Francis Crick, a biologist who shared a Nobel Prize for uncovering the structure of DNA, on a quest for what they called the “neural correlate of consciousness.” They believed that every conscious experience we have — gazing at a painting, for example — is associated with the activity of certain neurons essential for the awareness that comes with it. Dr. Chalmers liked the concept, but he was skeptical that they could find such a neural marker any time soon. Scientists still had too much to learn about consciousness and the brain, he figured, before they could have a reasonable hope of finding it. Dr. Koch wagered his friend that scientists would find a neural correlate of consciousness within 25 years. Dr. Chalmers took the bet. The prize would be a few bottles of fine wine. Recalling the bet from the auditorium stage, Dr. Koch admitted that it had been fueled by drinks and enthusiasm. “When you’re young, you’ve got to believe things will be simple,” he said. © 2023 The New York Times Company

Keyword: Consciousness
Link ID: 28839 - Posted: 07.01.2023

By John Horgan A neuroscientist clad in gold and red and a philosopher sheathed in black took the stage before a packed, murmuring auditorium at New York University on Friday night. The two men were grinning, especially the philosopher. They were here to settle a bet made in the late 1990s on one of science’s biggest questions: How does a brain, a lump of matter, generate subjective conscious states such as the blend of anticipation and nostalgia I felt watching these guys? Before I reveal their bet’s resolution, let me take you through its twisty backstory, which reveals why consciousness remains a topic of such fascination and frustration to anyone with even the slightest intellectual leaning. I first saw Christof Koch, the neuroscientist, and David Chalmers, the philosopher, butt heads in 1994 at a now legendary conference in Tucson, Ariz., called Toward a Scientific Basis for Consciousness. Koch was a star of the meeting. Together with biophysicist Francis Crick, he had been proclaiming in Scientific American and elsewhere that consciousness, which philosophers have wrestled with for millennia, was scientifically tractable. Just as Crick and geneticist James Watson solved heredity by decoding DNA’s double helix, scientists would crack consciousness by discovering its neural underpinnings, or “correlates.” Or so Crick and Koch claimed. They even identified a possible basis for consciousness: brain cells firing in synchrony 40 times per second. Advertisement Not everyone in Tucson was convinced. Chalmers, younger and then far less well known than Koch, argued that neither 40-hertz oscillations nor any other strictly physical process could account for why perceptions are accompanied by conscious sensations, such as the crushing boredom evoked by a jargony lecture. I have a vivid memory of the audience perking up when Chalmers called consciousness “the hard problem.” That was the first time I heard that now famous phrase.

Keyword: Consciousness
Link ID: 28836 - Posted: 06.28.2023

By Jordan Kinard Long the fixation of religions, philosophy and literature the world over, the conscious experience of dying has recently received increasingly significant attention from science. This comes as medical advances extend the ability to keep the body alive, steadily prying open a window into the ultimate locked room: the last living moments of a human mind. “Around 1959 humans discovered a method to restart the heart in people who would have died, and we called this CPR,” says Sam Parnia, a critical care physician at NYU Langone Health. Parnia has studied people’s recollections after being revived from cardiac arrest—phenomena that he refers to as “recalled experiences surrounding death.” Before CPR techniques were developed, cardiac arrest was basically synonymous with death. But now doctors can revive some people up to 20 minutes or more after their heart has stopped beating. Furthermore, Parnia says, many brain cells remain somewhat intact for hours to days postmortem—challenging our notions of a rigid boundary between life and death. Advancements in medical technology and neuroscience, as well as shifts in researchers’ perspectives, are revolutionizing our understanding of the dying process. Research over the past decade has demonstrated a surge in brain activity in human and animal subjects undergoing cardiac arrest. Meanwhile large surveys are documenting the seemingly inexplicable periods of lucidity that hospice workers and grieving families often report witnessing in people with dementia who are dying. Poet Dylan Thomas famously admonished his readers, “Do not go gentle into that good night. Rage, rage against the dying of the light.” But as more resources are devoted to the study of death, it is becoming increasingly clear that dying is not the simple dimming of one’s internal light of awareness but rather an incredibly active process in the brain. © 2023 Scientific American,

Keyword: Attention; Development of the Brain
Link ID: 28820 - Posted: 06.14.2023

By Claudia Lopez Lloreda Of all of COVID-19’s symptoms, one of the most troubling is “brain fog.” Victims report headaches, trouble concentrating, and forgetfulness. Now, researchers have shown that SARS-CoV-2 can cause brain cells to fuse together, disrupting their communication. Although the study was only done in cells in a lab dish, some scientists say it could help explain one of the pandemic’s most confounding symptoms. “This is a first important step,” says Stefan Lichtenthaler, a biochemist at the German Center for Neurodegenerative Diseases who was not involved with the work. Researchers already knew that SARS-CoV-2 could cause certain cells to fuse together. The lungs of patients who die from severe COVID-19 are often riddled with large, multicellular structures called syncytia, which scientists believe may contribute to the respiratory symptoms of the disease. Like other viruses, SARS-CoV-2 may incite cells to fuse to help it spread across an organ without having to infect new cells. To see whether such cell fusion might happen in brain cells, Massimo Hilliard, a neuroscientist at the University of Queensland, and his colleagues first genetically engineered two populations of mouse neurons: One expressed a red fluorescent molecule, and the other a green fluorescent molecule. If the two fused in a lab dish, they would show up as bright yellow under the microscope. That’s just what the researchers saw when they added SARS-CoV-2 to a dish containing both types of cells, they report today in Science Advances. The same fusion happened in human brain organoids, so-called minibrains that are created from stem cells. The key appears to be angiotensin-converting enzyme 2 (ACE2), the protein expressed on the surface of mammalian cells that SARS-CoV-2 is known to target. The virus uses a surface protein called spike to bind to ACE2, triggering the virus to fuse to a cell and release its genetic material inside. Seemingly, the spike protein in infected cells may also make other ACE2 on a cell trigger fusion to a neighboring cell. When the team engineered neurons to express the spike protein, only cells that also expressed ACE2 were able to fuse with each other. The findings parallel previous work in lung cells: The ACE2 receptor seems to be critical in mediating their fusion during SARS-CoV-2 infection.

Keyword: Neuroimmunology; Attention
Link ID: 28818 - Posted: 06.14.2023

By Steven Strogatz Neuroscience has made progress in deciphering how our brains think and perceive our surroundings, but a central feature of cognition is still deeply mysterious: namely, that many of our perceptions and thoughts are accompanied by the subjective experience of having them. Consciousness, the name we give to that experience, can’t yet be explained — but science is at least beginning to understand it. In this episode, the consciousness researcher Anil Seth and host Steven Strogatz discuss why our perceptions can be described as a “controlled hallucination,” how consciousness played into the internet sensation known as “the dress,” and how people at home can help researchers catalog the full range of ways that we experience the world. Steven Strogatz (00:03): I’m Steve Strogatz, and this is The Joy of Why, a podcast from Quanta Magazine that takes you into some of the biggest unanswered questions in math and science today. In this episode, we’re going to be discussing the mystery of consciousness. The mystery being that when your brain cells fire in certain patterns, it actually feels like something. It might feel like jealousy, or a toothache, or the memory of your mother’s face, or the scent of her favorite perfume. But other patterns of brain activity don’t really feel like anything at all. Right now, for instance, I’m probably forming some memories somewhere deep in my brain. But the process of that memory formation is imperceptible to me. I can’t feel it. It doesn’t give rise to any sort of internal subjective experience at all. In other words, I’m not conscious of it. (00:54) So how does consciousness happen? How is it related to physics and biology? Are animals conscious? What about plants? Or computers, could they ever be conscious? And what is consciousness exactly? My guest today, Dr. Anil Seth, studies consciousness in his role as the co-director of the Sussex Center for Consciousness Science at the University of Sussex, near Brighton, England. The Center brings together all sorts of disciplinary specialists, from neuroscientists to mathematicians to experts in virtual reality, to study the conscious experience. Dr. Seth is also the author of the book Being You: A New Science of Consciousness. He joins us from studios in Brighton, England. Anil, thanks for being here. All Rights Reserved © 2023

Keyword: Consciousness
Link ID: 28812 - Posted: 06.03.2023

By Yasemin Saplakoglu Is this the real life? Is this just fantasy? Those aren’t just lyrics from the Queen song “Bohemian Rhapsody.” They’re also the questions that the brain must constantly answer while processing streams of visual signals from the eyes and purely mental pictures bubbling out of the imagination. Brain scan studies have repeatedly found that seeing something and imagining it evoke highly similar patterns of neural activity. Yet for most of us, the subjective experiences they produce are very different. “I can look outside my window right now, and if I want to, I can imagine a unicorn walking down the street,” said Thomas Naselaris, an associate professor at the University of Minnesota. The street would seem real and the unicorn would not. “It’s very clear to me,” he said. The knowledge that unicorns are mythical barely plays into that: A simple imaginary white horse would seem just as unreal. So “why are we not constantly hallucinating?” asked Nadine Dijkstra, a postdoctoral fellow at University College London. A study she led, recently published in Nature Communications, provides an intriguing answer: The brain evaluates the images it is processing against a “reality threshold.” If the signal passes the threshold, the brain thinks it’s real; if it doesn’t, the brain thinks it’s imagined. They’ve done a great job, in my opinion, of taking an issue that philosophers have been debating about for centuries and defining models with predictable outcomes and testing them. Such a system works well most of the time because imagined signals are typically weak. But if an imagined signal is strong enough to cross the threshold, the brain takes it for reality. All Rights Reserved © 2023

Keyword: Attention
Link ID: 28803 - Posted: 05.27.2023

By Robert Martone Neurological conditions can release a torrent of new creativity in a few people as if opening some mysterious floodgate. Auras of migraine and epilepsy may have influenced a long list of artists, including Pablo Picasso, Vincent van Gogh, Edvard Munch, Giorgio de Chirico, Claude Monet and Georges Seurat. Traumatic brain injury (TBI) can result in original thinking and newfound artistic drive. Emergent creativity is also a rare feature of Parkinson’s disease. But this burst of creative ability is especially true of frontotemporal dementia (FTD). Although a few rare cases of FTD are linked to improvements in verbal creativity, such as greater poetic gifts and increased wordplay and punning, enhanced creativity in the visual arts is an especially notable feature of the condition. Fascinatingly, this burst of creativity indicates that the potential to create may rest dormant in some of us, only to be unleashed by a disease that also causes a loss of verbal abilities. The emergence of a vibrant creative spark in the face of devastating neurological disease speaks to the human brain’s remarkable potential and resilience. A new study published in JAMA Neurology examines the roots of this phenomenon and provides insight into a possible cause. As specific brain areas diminish in FTD, the researchers find, they release their inhibition, or control, of other regions that support artistic expression. Frontotemporal dementia is relatively rare—affecting about 60,000 people in the U. S.—and distinct from the far more common Alzheimer’s disease, a form of dementia in which memory deficits predominate. FTD is named for the two brain regions that can degenerate in this disease, specifically the frontal and temporal lobes.

Keyword: Alzheimers; Attention
Link ID: 28797 - Posted: 05.27.2023

By Yasemin Saplakoglu Memories are shadows of the past but also flashlights for the future. Our recollections guide us through the world, tune our attention and shape what we learn later in life. Human and animal studies have shown that memories can alter our perceptions of future events and the attention we give them. “We know that past experience changes stuff,” said Loren Frank, a neuroscientist at the University of California, San Francisco. “How exactly that happens isn’t always clear.” A new study published in the journal Science Advances now offers part of the answer. Working with snails, researchers examined how established memories made the animals more likely to form new long-term memories of related future events that they might otherwise have ignored. The simple mechanism that they discovered did this by altering a snail’s perception of those events. The researchers took the phenomenon of how past learning influences future learning “down to a single cell,” said David Glanzman, a cell biologist at the University of California, Los Angeles who was not involved in the study. He called it an attractive example “of using a simple organism to try to get understanding of behavioral phenomena that are fairly complex.” Although snails are fairly simple creatures, the new insight brings scientists a step closer to understanding the neural basis of long-term memory in higher-order animals like humans. Though we often aren’t aware of the challenge, long-term memory formation is “an incredibly energetic process,” said Michael Crossley, a senior research fellow at the University of Sussex and the lead author of the new study. Such memories depend on our forging more durable synaptic connections between neurons, and brain cells need to recruit a lot of molecules to do that. To conserve resources, a brain must therefore be able to distinguish when it’s worth the cost to form a memory and when it’s not. That’s true whether it’s the brain of a human or the brain of a “little snail on a tight energetic budget,” he said. All Rights Reserved © 2023

Keyword: Learning & Memory; Attention
Link ID: 28787 - Posted: 05.18.2023

By Laura Sanders Like Dumbledore’s wand, a scan can pull long strings of stories straight out of a person’s brain — but only if that person cooperates. This “mind-reading” feat, described May 1 in Nature Neuroscience, has a long way to go before it can be used outside of sophisticated laboratories. But the result could ultimately lead to seamless devices that help people who can’t talk or otherwise communicate easily. The research also raises privacy concerns about unwelcome neural eavesdropping (SN: 2/11/21). “I thought it was fascinating,” says Gopala Anumanchipalli, a neural engineer at the University of California, Berkeley who wasn’t involved in the study. “It’s like, ‘Wow, now we are here already,’” he says. “I was delighted to see this.” As opposed to implanted devices that have shown recent promise, the new system requires no surgery (SN: 11/15/22). And unlike other external approaches, it produces continuous streams of words instead of having a more constrained vocabulary. For the new study, three people lay inside a bulky MRI machine for at least 16 hours each. They listened to stories, mostly from The Moth podcast, while functional MRI scans detected changes in blood flow in the brain. These changes are proxies for brain activity, albeit slow and imperfect measures. With this neural data in hand, computational neuroscientists Alexander Huth and Jerry Tang of the University of Texas at Austin and colleagues were able to match patterns of brain activity to certain words and ideas. The approach relied on a language model that was built with GPT, one of the forerunners that enabled today’s AI chatbots (SN: 4/12/23). © Society for Science & the Public 2000–2023.

Keyword: Brain imaging; Consciousness
Link ID: 28769 - Posted: 05.03.2023

By Oliver Whang Think of the words whirling around in your head: that tasteless joke you wisely kept to yourself at dinner; your unvoiced impression of your best friend’s new partner. Now imagine that someone could listen in. On Monday, scientists from the University of Texas, Austin, made another step in that direction. In a study published in the journal Nature Neuroscience, the researchers described an A.I. that could translate the private thoughts of human subjects by analyzing fMRI scans, which measure the flow of blood to different regions in the brain. Already, researchers have developed language-decoding methods to pick up the attempted speech of people who have lost the ability to speak, and to allow paralyzed people to write while just thinking of writing. But the new language decoder is one of the first to not rely on implants. In the study, it was able to turn a person’s imagined speech into actual speech and, when subjects were shown silent films, it could generate relatively accurate descriptions of what was happening onscreen. “This isn’t just a language stimulus,” said Alexander Huth, a neuroscientist at the university who helped lead the research. “We’re getting at meaning, something about the idea of what’s happening. And the fact that that’s possible is very exciting.” The study centered on three participants, who came to Dr. Huth’s lab for 16 hours over several days to listen to “The Moth” and other narrative podcasts. As they listened, an fMRI scanner recorded the blood oxygenation levels in parts of their brains. The researchers then used a large language model to match patterns in the brain activity to the words and phrases that the participants had heard. © 2023 The New York Times Company

Keyword: Brain imaging; Consciousness
Link ID: 28768 - Posted: 05.03.2023

Sara Reardon The little voice inside your head can now be decoded by a brain scanner — at least some of the time. Researchers have developed the first non-invasive method of determining the gist of imagined speech, presenting a possible communication outlet for people who cannot talk. But how close is the technology — which is currently only moderately accurate — to achieving true mind-reading? And how can policymakers ensure that such developments are not misused? Most existing thought-to-speech technologies use brain implants that monitor activity in a person’s motor cortex and predict the words that the lips are trying to form. To understand the actual meaning behind the thought, computer scientists Alexander Huth and Jerry Tang at the University of Texas at Austin and their colleagues combined functional magnetic resonance imaging (fMRI), a non-invasive means of measuring brain activity, with artificial intelligence (AI) algorithms called large language models (LLMs), which underlie tools such as ChatGPT and are trained to predict the next word in a piece of text. In a study published in Nature Neuroscience on 1 May, the researchers had 3 volunteers lie in an fMRI scanner and recorded the individuals’ brain activity while they listened to 16 hours of podcasts each1. By measuring the blood flow through the volunteers’ brains and integrating this information with details of the stories they were listening to and the LLM’s ability to understand how words relate to one another, the researchers developed an encoded map of how each individual’s brain responds to different words and phrases. Next, the researchers recorded the participants’ fMRI activity while they listened to a story, imagined telling a story or watched a film that contained no dialogue. Using a combination of the patterns they had previously encoded for each individual and algorithms that determine how a sentence is likely to be constructed based on other words in it, the researchers attempted to decode this new brain activity. The video below shows the sentences produced from brain recordings taken while a study participant watched a clip from the animated film Sintel about a girl caring for a baby dragon. © 2023 Springer Nature Limited

Keyword: Brain imaging; Consciousness
Link ID: 28767 - Posted: 05.03.2023

By Sara Reardon Many people who have come close to death or have been resuscitated report a similar experience: Their lives flash before their eyes, memorable moments replay, and they may undergo an out-of-body experience, sensing they’re looking at themselves from elsewhere in the room. Now, a small study mapping the brain activity of four people while they were dying shows a burst of activity in their brains after their hearts stop. The authors say the finding, published today in the Proceedings of the National Academy of Sciences, may explain how a person’s brain could replay conscious memories even after the heart has stopped. It “suggests we are identifying a marker of lucid consciousness,” says Sam Parnia, a pulmonologist at New York University Langone Medical Center who was not involved in the study. Although death has historically been medically defined as the moment when the heart irreversibly stops beating, recent studies have suggested brain activity in many animals and humans can continue for seconds to hours. In 2013, for instance, University of Michigan neurologist Jimo Borjigin and team found that rats’ brains showed signs of consciousness up to 30 seconds after their hearts had stopped beating. “We have this binary concept of life and death that is ancient and outdated,” Parnia says. Still, despite the numerous reports over hundreds of years from people who have been resuscitated following clinical death or nearly died, “I was shocked to realize we know almost nothing” about brain activity during the dying process, Borjigin says. For the current study, she and her team looked at the medical records of four people who were in comas and on life support on whom physicians had placed electroencephalography caps. None of the patients had any chance of survival.

Keyword: Attention; Consciousness
Link ID: 28765 - Posted: 05.03.2023

By Tim Vernimmen This story starts in an unusual place for an article about human nutrition: a cramped, humid and hot room somewhere in the Zoology building of the University of Oxford in England, filled with a couple hundred migratory locusts, each in its own plastic box. It was there, in the late 1980s, that entomologists Stephen Simpson and David Raubenheimer began working together on a curious job: rearing these notoriously voracious insects, to try and find out whether they were picky eaters. Every day, Simpson and Raubenheimer would weigh each locust and feed it precise amounts of powdered foods containing varying proportions of proteins and carbohydrates. To their surprise, the young scientists found that whatever food the insects were fed, they ended up eating almost exactly the same amount of protein. In fact, locusts feeding on food that was low in protein ate so much extra in order to reach their protein target that they ended up overweight — not chubby on the outside, since their exoskeleton doesn’t allow for bulges, but chock-full of fat on the inside. Inevitably, this made Simpson and Raubenheimer wonder whether something similar might be causing the documented rise in obesity among humans. Many studies had reported that even as our consumption of fats and carbohydrates increased, our consumption of protein did not. Might it be that, like locusts, we are tricked into overeating, in our case by the irresistible, low-protein, ultraprocessed foods on the shelves of the stores where we do most of our foraging? That’s what Raubenheimer and Simpson, both now at the University of Sydney, argue in their recent book “Eat Like the Animals” and in an overview in the Annual Review of Nutrition. © 2023 Annual Reviews

Keyword: Obesity; Attention
Link ID: 28764 - Posted: 05.03.2023

Ruth Ogden A year and half alone in a cave might sound like a nightmare to a lot of people, but Spanish athlete Beatriz Flamini emerged with a cheerful grin and said she thought she had more time to finish her book. She had almost no contact with the outside world during her impressive feat of human endurance. For 500 days, she documented her experiences to help scientists understand the effects of extreme isolation. One of the first things that became apparent on April 12 2023 when she emerged from the cave was how fluid time is, shaped more by your personality traits and the people around you than a ticking clock. When talking to reporters about her experiences, Flamini explained she rapidly lost her sense of time. The loss of time was so profound that, when her support team came to retrieve her, she was surprised that her time was up, instead believing she had only been there for 160-170 days. Our actions, emotions and changes in our environment can have powerful effects on the way in which our minds process time. For most people, the rising and setting of the sun mark the passing of days, and work and social routines mark the passing of hours. In the darkness of an underground cave, without the company of others, many signals of passing of time will have disappeared. So Flamini may have become more reliant on psychological processes to monitor time. One way in which we keep track of the passage of time is memory. If we don’t know how long we have been doing something for, we use the number of memories formed during the event as an index to the amount of time that has passed. The more memories we form in an event or era, the longer we perceive it to have lasted. © 2010–2023, The Conversation US, Inc.

Keyword: Attention; Biological Rhythms
Link ID: 28755 - Posted: 04.26.2023

By Emily Underwood The ability to set a goal and pursue it without getting derailed by temptations or distractions is essential to nearly everything we do in life, from finishing homework to driving safely in traffic. It also places complex demands on the brain, requiring skills like working memory — the ability to keep small amounts of information in mind to perform a task — as well as impulse control and being able to rapidly adapt when rules or circumstances change. Taken together, these elements add up to something researchers call executive function. We all struggle with executive function sometimes, for example when we’re stressed or don’t get enough sleep. But in teenagers, these powers are still a work in progress, contributing to some of the contradictory behaviors and lapses in judgment — “My honor roll student did what on TikTok?” — that baffle many parents. This erratic control can be dangerous, especially when teens make impulsive choices. But that doesn’t mean the teen brain is broken, says Beatriz Luna, a developmental cognitive neuroscientist at the University of Pittsburgh and coauthor of a review on the maturation of one aspect of executive function, called cognitive control, in the 2015 Annual Review of Neuroscience. Adolescents have all the basic neural circuitry needed for executive function and cognitive control, Luna says. In fact, they have more than they need — what’s lacking is experience, which over time will strengthen some neural pathways and weaken or eliminate others. This winnowing serves an important purpose: It tailors the brain to help teens handle the demands of their unique, ever-changing environments and to navigate situations their parents may never have encountered. Luna’s research suggests that teens’ inconsistent cognitive control is key to becoming independent, because it encourages them to seek out and learn from experiences that go beyond what they’ve been actively taught. © 2023 Annual Reviews

Keyword: Development of the Brain; Attention
Link ID: 28751 - Posted: 04.26.2023

Nicola Davis Science Correspondent If the sound of someone chewing gum or slurping their tea gets on your nerves, you are not alone. Researchers say almost one in five people in the UK has strong negative reactions to such noises. Misophonia is a disorder in which people feel strong emotional responses to certain sounds, feeling angry, distressed or even unable to function in social or work settings as a result. But just how common the condition is has been a matter of debate. Now researchers say they have found 18.4% of the UK population have significant symptoms of misophonia. “This is the very first study where we have a representative sample of the UK population,” said Dr Silia Vitoratou, first author of the study at King’s College London. “Most people with misophonia think they are alone, but they are not. This is something we need to know [about] and make adjustments if we can.” Writing in the journal Plos One, the team report how they gathered responses from 768 people using metrics including the selective sound sensitivity syndrome scale. This included one questionnaire probing the sounds that individuals found triggering, such as chewing or snoring, and another exploring the impact of such sounds – including whether they affected participants’ social life and whether the participant blamed the noise-maker – as well as the type of emotional response participants felt to the sounds and the intensity of their emotions. As a result, each participant was given an overall score. The results reveal more than 80% of participants had no particular feelings towards sounds such as “normal breathing” or “yawning” but this plummeted to less than 25% when it came to sounds including “slurping”, “chewing gum” and “sniffing”. © 2023 Guardian News & Media Limited

Keyword: Hearing; Attention
Link ID: 28712 - Posted: 03.23.2023

By Ellen Barry It is a truism that time seems to expand or contract depending on our circumstances: In a state of terror, seconds can stretch. A day spent in solitude can drag. When we’re trying to meet a deadline, hours race by. A study published this month in the journal Psychophysiology by psychologists at Cornell University found that, when observed at the level of microseconds, some of these distortions could be driven by heartbeats, whose length is variable from moment to moment. The psychologists fitted undergraduates with electrocardiograms to measure the length of each heartbeat precisely, and then asked them to estimate the length of brief audio tones. The psychologists discovered that after a longer heartbeat interval, subjects tended to perceive the tone as longer; shorter intervals led subjects to assess the tone as shorter. Subsequent to each tone, the subjects’ heartbeat intervals lengthened. A lower heart rate appeared to assist with perception, said Saeedeh Sadeghi, a doctoral candidate at Cornell and the study’s lead author. “When we need to perceive things from the outside world, the beats of the heart are noise to the cortex,” she said. “You can sample the world more — it’s easier to get things in — when the heart is silent.” The study provides more evidence, after an era of research focusing on the brain, that “there is no single part of the brain or body that keeps time — it’s all a network,” she said, adding, “The brain controls the heart, and the heart, in turn, impacts the brain.” Interest in the perception of time has exploded since the Covid pandemic, when activity outside the home came to an abrupt halt for many and people around the world found themselves facing stretches of undifferentiated time. A study of time perception conducted during the first year of the lockdown in Britain found that 80 percent of participants reported distortions in time, in different directions. On average, older, more socially isolated people reported that time slowed, and younger, more active people reported that it sped up. © 2023 The New York Times Company

Keyword: Attention
Link ID: 28704 - Posted: 03.15.2023

By Marta Zaraska The Neumayer III polar station sits near the edge of Antarctica’s unforgiving Ekström Ice Shelf. During the winter, when temperatures can plunge below minus 50 degrees Celsius and the winds can climb to more than 100 kilometers per hour, no one can come or go from the station. Its isolation is essential to the meteorological, atmospheric and geophysical science experiments conducted there by the mere handful of scientists who staff the station during the winter months and endure its frigid loneliness. But a few years ago, the station also became the site for a study of loneliness itself. A team of scientists in Germany wanted to see whether the social isolation and environmental monotony marked the brains of people making long Antarctic stays. Eight expeditioners working at the Neumayer III station for 14 months agreed to have their brains scanned before and after their mission and to have their brain chemistry and cognitive performance monitored during their stay. (A ninth crew member also participated but could not have their brain scanned for medical reasons.) As the researchers described in 2019, in comparison to a control group, the socially isolated team lost volume in their prefrontal cortex — the region at the front of the brain, just behind the forehead, that is chiefly responsible for decision-making and problem-solving. They also had lower levels of brain-derived neurotrophic factor, a protein that nurtures the development and survival of nerve cells in the brain. The reduction persisted for at least a month and a half after the team’s return from Antarctica. It’s uncertain how much of this was due purely to the social isolation of the experience. But the results are consistent with evidence from more recent studies that chronic loneliness significantly alters the brain in ways that only worsen the problem. Neuroscience suggests that loneliness doesn’t necessarily result from a lack of opportunity to meet others or a fear of social interactions. Instead, circuits in our brain and changes in our behavior can trap us in a catch-22 situation: While we desire connection with others, we view them as unreliable, judgmental and unfriendly. Consequently, we keep our distance, consciously or unconsciously spurning potential opportunities for connections. Simons Foundation All Rights Reserved © 2023

Keyword: Stress; Attention
Link ID: 28689 - Posted: 03.04.2023

By Stephani Sutherland Tara Ghormley has always been an overachiever. She finished at the top of her class in high school, graduated summa cum laude from college and earned top honors in veterinary school. She went on to complete a rigorous training program and build a successful career as a veterinary internal medicine specialist. But in March 2020 she got infected with the SARS-CoV-2 virus—just the 24th case in the small, coastal central California town she lived in at the time, near the site of an early outbreak in the COVID pandemic. “I could have done without being first at this,” she says. Almost three years after apparently clearing the virus from her body, Ghormley is still suffering. She gets exhausted quickly, her heartbeat suddenly races, and she goes through periods where she can't concentrate or think clearly. Ghormley and her husband, who have relocated to a Los Angeles suburb, once spent their free time visiting their “happiest place on Earth”—Disneyland—but her health prevented that for more than a year. She still spends most of her days off resting in the dark or going to her many doctors' appointments. Her early infection and ongoing symptoms make her one of the first people in the country with “long COVID,” a condition where symptoms persist for at least three months after the infection and can last for years. The syndrome is known by medical professionals as postacute sequelae of COVID-19, or PASC. People with long COVID have symptoms such as pain, extreme fatigue and “brain fog,” or difficulty concentrating or remembering things. As of February 2022, the syndrome was estimated to affect about 16 million adults in the U.S. and had forced between two million and four million Americans out of the workforce, many of whom have yet to return. Long COVID often arises in otherwise healthy young people, and it can follow even a mild initial infection. The risk appears at least slightly higher in people who were hospitalized for COVID and in older adults (who end up in the hospital more often). Women and those at socioeconomic disadvantage also face higher risk, as do people who smoke, are obese, or have any of an array of health conditions, particularly autoimmune disease. Vaccination appears to reduce the danger but does not entirely prevent long COVID.

Keyword: Attention; Learning & Memory
Link ID: 28667 - Posted: 02.15.2023

By Betsy Mason Some fish can recognize their own faces in photos and mirrors, an ability usually attributed to humans and other animals considered particularly brainy, such as chimpanzees, scientists report. Finding the ability in fish suggests that self-awareness may be far more widespread among animals than scientists once thought. “It is believed widely that the animals that have larger brains will be more intelligent than animals of the small brain,” such as fish, says animal sociologist Masanori Kohda of Osaka Metropolitan University in Japan. It may be time to rethink that assumption, Kohda says. Kohda’s previous research showed that bluestreak cleaner wrasses can pass the mirror test, a controversial cognitive assessment that purportedly reveals self-awareness, or the ability to be the object of one’s own thoughts. The test involves exposing an animal to a mirror and then surreptitiously putting a mark on the animal’s face or body to see if they will notice it on their reflection and try to touch it on their body. Previously only a handful of large-brained species, including chimpanzees and other great apes, dolphins, elephants and magpies, have passed the test. In a new study, cleaner fish that passed the mirror test were then able to distinguish their own faces from those of other cleaner fish in still photographs. This suggests that the fish identify themselves the same way humans are thought to — by forming a mental image of one’s face, Kohda and colleagues report February 6 in the Proceedings of the National Academy of Sciences. “I think it’s truly remarkable that they can do this,” says primatologist Frans de Waal of Emory University in Atlanta who was not involved in the research. “I think it’s an incredible study.” © Society for Science & the Public 2000–2023.

Keyword: Attention; Evolution
Link ID: 28659 - Posted: 02.08.2023