Chapter 14. Attention and Consciousness
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By Susana Martinez-Conde, Stephen L. Macknik We think we know what we want—but do we, really? In 2005 Lars Hall and Petter Johansson, both at Lund University in Sweden, ran an experiment that transformed how cognitive scientists think about choice. The experimental setup looked deceptively simple. A study participant and researcher faced each other across a table. The scientist offered two photographs of young women deemed equally attractive by an independent focus group. The subject then had to choose which portrait he or she found more appealing. Next, the experimenter turned both pictures over, moved them toward the subjects and asked them to pick up the photo they just chose. Subjects complied, unaware that the researcher had just performed a swap using a sleight-of-hand technique known to conjurers as black art. Because your visual neurons are built to detect and enhance contrast, it is very hard to see black on black: a magician dressed in black against a black velvet backdrop can look like a floating head. Hall and Johansson deliberately used a black tabletop in their experiment. The first photos their subjects saw all had black backs. Behind those, however, they hid a second picture of the opposite face with a red back. When the experimenter placed the first portrait face down on the table, he pushed the second photo toward the subject. When participants picked up the red-backed photos, the black-backed ones stayed hidden against the table's black surface—that is, until the experimenter could surreptitiously sweep them into his lap. © 2016 Scientific American
By Victoria Gill Science reporter, BBC News Direct recordings have revealed what is happening in our brains as we make sense of speech in a noisy room. Focusing on one conversation in a loud, distracting environment is called "the cocktail party effect". It is a common festive phenomenon and of interest to researchers seeking to improve speech recognition technology. Neuroscientists recorded from people's brains during a test that recreated the moment when unintelligible speech suddenly makes sense. A team measured people's brain activity as the words of a previously unintelligible sentence suddenly became clear when a subject was told the meaning of the "garbled speech". The findings are published in the journal Nature Communications. Lead researcher Christopher Holdgraf from the University of California, Berkeley, and his colleagues were able to work with epilepsy patients, who had had a portion of their skull removed and electrodes placed on the brain surface to track their seizures. First, the researchers played a very distorted, garbled sentence to each subject, which almost no-one was able to understand. They then played a normal, easy to understand version of the same sentence and immediately repeated the garbled version. "After hearing the intact sentence" the researchers explained in their paper, all the subjects understood the subsequent "noisy version". The brain recordings showed this moment of recognition as brain activity patterns in the areas of the brain that are known to be associated with processing sound and understanding speech. When the subjects heard the very garbled sentence, the scientists reported that they saw little activity in those parts of the brain. Hearing the clearly understandable sentence then triggered patterns of activity in those brain areas. © 2016 BBC.
A little over a decade ago, neuroscientists began using a new technique to inspect what was going on in the brains of their subjects. Rather than giving their subjects a task to complete and watching their brains to see which parts lit up, they’d tell them to lie back, let their minds wander, and try not to fall asleep for about six minutes. That technique is called resting state functional magnetic resonance imaging, and it shares a problem with other types of fMRI: It only tracks changes in the blood in the brain, not the neurons sending the signals in the first place. Researchers have recently called fMRI into question for its reliance on possibly-faulty statistics. And things get even less certain when the brain isn’t engaged in any particular task. “These signals are, by definition, random,” says Elizabeth Hillman, a biomedical engineer at Columbia’s Zuckerman Institute. “And when you’re trying to measure something that’s random amidst a whole bunch of noise, it becomes very hard to tell what’s actually random and what isn’t.” Six years ago, Hillman, along with many others in the field, was deeply skeptical of resting state fMRI’s ability to measure what it promised to. But this week, in a paper in Proceedings of the National Academy of Sciences, she presents compelling evidence to the contrary: a comprehensive visualization of neural activity throughout the entire brain at rest, and evidence that the blood rushing around in your brain is actually a good indicator of what your neurons are doing. Ever since 1992, when researcher Bharat Biswal first started scanning people who were just sitting around, resting state fMRI has become increasingly popular. Partly, that’s because it’s just way simpler than regular, task-based fMRI.
Answer by Paul King, Director of Data Science, on Quora: There are hundreds of surprising, perspective-shifting insights about the nature of reality that come from neuroscience. Every bizarre neurological syndrome, every visual illusion, and every clever psychological experiment reveals something entirely unexpected about our experience of the world that we take for granted. Here are a few to give a flavor: 1. Perceptual reality is entirely generated by our brain. We hear voices and meaning from air pressure waves. We see colors and objects, yet our brain only receives signals about reflected photons. The objects we perceive are a construct of the brain, which is why optical illusions can fool the brain. Recommended by Forbes 2. We see the world in narrow disjoint fragments. We think we see the whole world, but we are looking through a narrow visual portal onto a small region of space. You have to move your eyes when you read because most of the page is blurry. We don't see this, because as soon as we become curious about part of the world, our eyes move there to fill in the detail before we see it was missing. While our eyes are in motion, we should see a blank blur, but our brain edits this out. 3. Body image is dynamic and flexible. Our brain can be fooled into thinking a rubber arm or a virtual reality hand is actually a part of our body. In one syndrome, people believe one of their limbs does not belong to them. One man thought a cadaver limb had been sewn onto his body as a practical joke by doctors. 4. Our behavior is mostly automatic, even though we think we are controlling it.
Link ID: 22980 - Posted: 12.13.2016
By DANIEL A. YUDKIN and JAY VAN BAVEL During the first presidential debate, Hillary Clinton argued that “implicit bias is a problem for everyone, not just police.” Her comment moved to the forefront of public conversation an issue that scientists have been studying for decades: namely, that even well-meaning people frequently harbor hidden prejudices against members of other racial groups. Studies have shown that these subtle biases are widespread and associated with discrimination in legal, economic and organizational settings. Critics of this notion, however, protest what they see as a character smear — a suggestion that everybody, deep down, is racist. Vice President-elect Mike Pence has said that an “accusation of implicit bias” in cases where a white police officer shoots a black civilian serves to “demean law enforcement.” Writing in National Review, David French claimed that the concept of implicit bias lets people “indict entire communities as bigoted.” But implicit bias is not about bigotry per se. As new research from our laboratory suggests, implicit bias is grounded in a basic human tendency to divide the social world into groups. In other words, what may appear as an example of tacit racism may actually be a manifestation of a broader propensity to think in terms of “us versus them” — a prejudice that can apply, say, to fans of a different sports team. This doesn’t make the effects of implicit bias any less worrisome, but it does mean people should be less defensive about it. Furthermore, our research gives cause for optimism: Implicit bias can be overcome with rational deliberation. In a series of experiments whose results were published in The Journal of Experimental Psychology: General, we set out to determine how severely people would punish someone for stealing. Our interest was in whether a perpetrator’s membership in a particular group would influence the severity of the punishment he or she received. © 2016 The New York Times Company
Children don’t usually have the words to communicate even the darkest of thoughts. As a result, some children aged 5 to 11 take their own lives. It’s a rare and often overlooked phenomenon—and one that scientists are only just beginning to understand. A study published today in the journal Pediatrics reveals that attention deficit disorder (A.D.D.), not depression, may be the most common mental health diagnosis among children who die by suicide. By contrast, the researchers found that two-thirds of the 606 early adolescents studied (aged 12 to 14) had suffered from depression. While the finding isn’t necessarily causal, it does suggest that impulsive behavior might contribute to incidences of child suicide. Alternatively, some of these cases could be attributed to early-onset bipolar disorder, misdiagnosed as A.D.D. or A.D.H.D. Here’s Catherine Saint Louis, reporting for The New York Times: Suicide prevention has focused on identifying children struggling with depression; the new study provides an early hint that this strategy may not help the youngest suicide victims. “Maybe in young children, we need to look at behavioral markers,” said Jeffrey Bridge, the paper’s senior author and an epidemiologist at the Research Institute at Nationwide Children’s Hospital in Columbus, Ohio. Jill Harkavy-Friedman, the vice president of research at the American Foundation for Suicide Prevention, agreed. “Not everybody who is at risk for suicide has depression,” even among adults, said Dr. Harkavy-Friedman, who was not involved in the new research. © 1996-2016 WGBH Educational Foundation
Rosie Mestel The 2016 US election was a powerful reminder that beliefs tend to come in packages: socialized medicine is bad, gun ownership is a fundamental right, and climate change is a myth — or the other way around. Stances that may seem unrelated can cluster because they have become powerful symbols of membership of a group, says Dan Kahan, who teaches law and psychology at Yale Law School in New Haven, Connecticut. And the need to keep believing can further distort people’s perceptions and their evaluation of evidence. Here, Kahan tells Nature about the real-world consequences of group affinity and cognitive bias, and about research that may point to remedies. This interview has been edited for length and clarity. One measure is how individualistic or communitarian people are, and how egalitarian or hierarchical. Hierarchical and individualistic people tend to have confidence in markets and industry: those represent human ingenuity and power. People who are egalitarian and communitarian are suspicious of markets and industry. They see them as responsible for social disparity. It’s natural to see things you consider honourable as good for society, and things that are base, as bad. Such associations will motivate people’s assessment of evidence. Can you give an example? In a study, we showed people data from gun-control experiments and varied the results1. People who were high in numeracy always saw when a study supported their view. If it didn’t support their view, they didn’t notice — or argued their way out of it. © 2016 Macmillan Publishers Limited
By Alison Howell What could once only be imagined in science fiction is now increasingly coming to fruition: Drones can be flown by human brains' thoughts. Pharmaceuticals can help soldiers forget traumatic experiences or produce feelings of trust to encourage confession in interrogation. DARPA-funded research is working on everything from implanting brain chips to "neural dust" in an effort to alleviate the effects of traumatic experience in war. Invisible microwave beams produced by military contractors and tested on U.S. prisoners can produce the sensation of burning at a distance. What all these techniques and technologies have in common is that they're recent neuroscientific breakthroughs propelled by military research within a broader context of rapid neuroscientific development, driven by massive government-funded projects in both America and the European Union. Even while much about the brain remains mysterious, this research has contributed to the rapid and startling development of neuroscientific technology. And while we might marvel at these developments, it is also undeniably true that this state of affairs raises significant ethical questions. What is the proper role – if any – of neuroscience in national defense or war efforts? My research addresses these questions in the broader context of looking at how international relations, and specifically warfare, are shaped by scientific and medical expertise and technology. 2016 © U.S. News & World Report L.P.
Amanda Gefter As we go about our daily lives, we tend to assume that our perceptions—sights, sounds, textures, tastes—are an accurate portrayal of the real world. Sure, when we stop and think about it—or when we find ourselves fooled by a perceptual illusion—we realize with a jolt that what we perceive is never the world directly, but rather our brain’s best guess at what that world is like, a kind of internal simulation of an external reality. Still, we bank on the fact that our simulation is a reasonably decent one. If it wasn’t, wouldn’t evolution have weeded us out by now? The true reality might be forever beyond our reach, but surely our senses give us at least an inkling of what it’s really like. Not so, says Donald D. Hoffman, a professor of cognitive science at the University of California, Irvine. Hoffman has spent the past three decades studying perception, artificial intelligence, evolutionary game theory and the brain, and his conclusion is a dramatic one: The world presented to us by our perceptions is nothing like reality. What’s more, he says, we have evolution itself to thank for this magnificent illusion, as it maximizes evolutionary fitness by driving truth to extinction. Getting at questions about the nature of reality, and disentangling the observer from the observed, is an endeavor that straddles the boundaries of neuroscience and fundamental physics. On one side you’ll find researchers scratching their chins raw trying to understand how a three-pound lump of gray matter obeying nothing more than the ordinary laws of physics can give rise to first-person conscious experience. This is the aptly named “hard problem.”
Link ID: 22937 - Posted: 12.01.2016
By Melissa Dahl Considering its origin story, it’s not so surprising that hypnosis and serious medical science have often seemed at odds. The man typically credited with creating hypnosis, albeit in a rather primitive form, is Franz Mesmer, a doctor in 18th-century Vienna. (Mesmer, mesmerize. Get it?) Mesmer developed a general theory of disease he called “animal magnetism,” which held that every living thing carries within it an internal magnetic force, in liquid form. Illness arises when this fluid becomes blocked, and can be cured if it can be coaxed to flow again, or so Mesmer’s thinking went. To get that fluid flowing, as science journalist Jo Marchant describes in her recent book, Cure, Mesmer “simply waved his hands to direct it through his patients’ bodies” — the origin of those melodramatic hand motions that stage hypnotists use today.” After developing a substantial following — “mesmerism” became “the height of fashion” in late 1780s Paris, writes Marchant — Mesmer became the subject of what was essentially the world’s first clinical trial. King Louis XVI pulled together a team of the world’s top scientists, including Benjamin Franklin, who tested mesmerism and found its capacity to “cure” was, essentially, a placebo effect. “Not a shred of evidence exists for any fluid,” Franklin wrote. “The practice … is the art of increasing the imagination by degrees.” Maybe so. But that doesn’t mean it doesn’t work. © 2016, New York Media LLC.
By Yasemin Saplakoglu Even if you don’t have rhythm, your pupils do. In a new study, neuroscientists played drumming patterns from Western music, including beats typical in pop and rock, while asking volunteers to focus on computer screens for an unrelated fast-paced task that involved pressing the space bar as quickly as possible in response to a signal on the screen. Unbeknownst to the participants, the music omitted strong and weak beats at random times. (You can listen below for an example of a music clip they used. If you listen carefully, you can hear bass and hi-hat beats omitted throughout.) Eye scanners tracked the dilations of the subjects’ pupils as the music played. Their pupils enlarged when the rhythms dropped certain beats, even though the participants weren’t paying attention to the music. The biggest dilations matched the omissions of the beats in the most prominent locations in the music, usually the important first beat in a repeated set of notes. The results suggest that we may have an automatic sense of “hierarchical meter”—a pattern of strong and weak beats—that governs our expectations of music, the researchers write in the February 2017 issue of Brain and Cognition. Perhaps, the authors say, our eyes reveal clues into the importance that music and rhythm plays in our lives. © 2016 American Association for the Advancement of Science
Ian Sample Science editor Scientists have raised hopes for a radical new therapy for phobias and post-traumatic stress disorder (PTSD) with a procedure that can dampen down fears linked to painful memories. The advance holds particular promise for patients because in early tests, researchers found they could reduce anxieties triggered by specific memories without asking people to think about them consciously. That could make it more appealing than exposure therapy, which aims to help patients overcome their phobias by making them confront their fears in a safe environment, for example by encouraging them to handle spiders or snakes in the clinic. The new technique, called fMRI decoded neurofeedback (DecNef), was developed by scientists at the ATR Computational Neuroscience Lab in Japan. Mitsuo Kawato, who worked with researchers in the UK and the US on the latest study, said he wanted to find an alternative to exposure therapy, which has a 40% drop-out rate among PTSD patients. “We always thought this was ambitious, but it worked the way we hoped it would,” said Ben Seymour, a clinical neuroscientist and member of the team at Cambridge University. “We don’t completely erase the fear memory, but it is substantially reduced.” The procedure uses a computer algorithm to analyse a patient’s brain activity in real time and pinpoint moments when their fears can be overwritten by giving them a reward. In the latest study, the reward was a small amount of money. © 2016 Guardian News and Media Limited
By R. Douglas Fields SAN DIEGO—A wireless device that decodes brain waves has enabled a woman paralyzed by locked-in syndrome to communicate from the comfort of her home, researchers announced this week at the annual meeting of the Society for Neuroscience. The 59-year-old patient, who prefers to remain anonymous but goes by the initials HB, is “trapped” inside her own body, with full mental acuity but completely paralyzed by a disease that struck in 2008 and attacked the neurons that make her muscles move. Unable to breathe on her own, a tube in her neck pumps air into her lungs and she requires round-the-clock assistance from caretakers. Thanks to the latest advance in brain–computer interfaces, however, HB has at least regained some ability to communicate. The new wireless device enables her to select letters on a computer screen using her mind alone, spelling out words at a rate of one letter every 56 seconds, to share her thoughts. “This is a significant achievement. Other attempts on such an advanced case have failed,” says neuroscientist Andrew Schwartz of the University of Pittsburgh, who was not involved in the study, published in The New England Journal of Medicine. HB’s mind is intact and the part of her brain that controls her bodily movements operates perfectly, but the signals from her brain no longer reach her muscles because the motor neurons that relay them have been damaged by amyotrophic lateral sclerosis (ALS), says neuroscientist Erick Aarnoutse, who designed the new device and was responsible for the technical aspects of the research. He is part of a team of physicians and scientists led by neuroscientist Nick Ramsey at Utrecht University in the Netherlands. Previously, the only way HB could communicate was via a system that uses an infrared camera to track her eye movements. But the device is awkward to set up and use for someone who cannot move, and it does not function well in many situations, such as in bright sunlight. © 2016 Scientific American,
Laurence O'Dwyer Until as late as 2013 a joint (or comorbid) diagnosis of autism and attention deficit hyperactivity disorder (ADHD) was not permitted by the most influential psychiatric handbook, the Diagnostic and Statistical Manual of Mental Disorders (DSM). The DSM is an essential tool in psychiatry as it allows clinicians and researchers to use a standard framework for classifying mental disorders. Health insurance companies and drug regulation agencies also use the DSM, so its definition of what does or doesn’t constitute a particular disorder can have far-reaching consequences. One of the reasons for the prohibition of a comorbid diagnosis of autism and ADHD was that the severity of autism placed it above ADHD in the diagnostic hierarchy, so the inattention that is normally present in autism did not seem to merit an additional diagnosis. Nevertheless, that was an odd state of affairs, as any clinician working in the field would be able to quote studies that point to anything from 30% to 80% of patients with autism also having ADHD. More problematic still is the fact that patients with both sets of symptoms may respond poorly to standard ADHD treatments or have increased side effects. The fifth edition of the DSM opened the way for a more detailed look at this overlap, and just a year after the new guidelines were adopted, a consortium (which I am a part of) at the Radboud University in Nijmegen (Netherlands) called NeuroIMAGE published a paper which showed that autistic traits in ADHD participants could be predicted by complex interactions between grey and white matter volumes in the brain. © 2016 Guardian News and Media Limited
Ian Sample Science editor US military scientists have used electrical brain stimulators to enhance mental skills of staff, in research that aims to boost the performance of air crews, drone operators and others in the armed forces’ most demanding roles. The successful tests of the devices pave the way for servicemen and women to be wired up at critical times of duty, so that electrical pulses can be beamed into their brains to improve their effectiveness in high pressure situations. The brain stimulation kits use five electrodes to send weak electric currents through the skull and into specific parts of the cortex. Previous studies have found evidence that by helping neurons to fire, these minor brain zaps can boost cognitive ability. The technology is seen as a safer alternative to prescription drugs, such as modafinil and ritalin, both of which have been used off-label as performance enhancing drugs in the armed forces. But while electrical brain stimulation appears to have no harmful side effects, some experts say its long-term safety is unknown, and raise concerns about staff being forced to use the equipment if it is approved for military operations. Others are worried about the broader implications of the science on the general workforce because of the advance of an unregulated technology. © 2016 Guardian News and Media Limited
By Chelsea Whyte FACING a big problem and finding it hard to decide what to do? A sprinkling of disgust might boost your confidence. Common sense suggests that our confidence in the decisions we make comes down to the quality of the information available – the clearer that information, the more confident we feel. But it seems that the state of our body also guides us. Micah Allen at University College London and his colleagues showed 29 people a screen of dots moving in varied directions. They asked the volunteers which direction most of the spots were moving in, and how confident they were in their decisions. Before each task, the participants briefly saw a picture of a face on the screen. It was either twisted in disgust or had a neutral expression. Although this happened too quickly for the faces to be consciously perceived, the volunteers’ bodies reacted. Seeing disgust, which is a powerful evolutionary sign of danger, boosted the volunteers’ alertness, pushing up their heart rates and dilating their pupils. “When you induce disgust, high confidence becomes lower and low confidence becomes higher“ When shown a neutral face, the volunteers became less confident as the task got more difficult. As the movement of the dots became more varied, they were less sure of the main direction. But when they were shown the disgusted face, they reacted differently. In easy tasks, in which people were previously confident, they became more doubtful of their decisions. In more difficult tasks, their confidence grew. Neither face made any difference to the accuracy of their answers (eLife, doi.org/bsgd). © Copyright Reed Business Information Ltd.
Hannah Devlin The human brain is predisposed to learn negative stereotypes, according to research that offers clues as to how prejudice emerges and spreads through society. The study found that the brain responds more strongly to information about groups who are portrayed unfavourably, adding weight to the view that the negative depiction of ethnic or religious minorities in the media can fuel racial bias. Hugo Spiers, a neuroscientist at University College London, who led the research, said: “The newspapers are filled with ghastly things people do ... You’re getting all these news stories and the negative ones stand out. When you look at Islam, for example, there’s so many more negative stories than positive ones and that will build up over time.” The scientists also uncovered a characteristic brain signature seen when participants were told a member of a “bad” group had done something positive - an observation that is likely to tally with the subjective experience of minorities. “Whenever someone from a really bad group did something nice they were like, ‘Oh, weird,’” said Spiers. Previous studies have identified brain areas involved in gender or racial stereotyping, but this is the first attempt to investigate how the brain learns to link undesirable traits to specific groups and how this is converted into prejudice over time. © 2016 Guardian News and Media Limited
Link ID: 22821 - Posted: 11.02.2016
Laura Sanders The eyes may reveal whether the brain’s internal stopwatch runs fast or slow. Pupil size predicted whether a monkey would over- or underestimate a second, scientists report in the Nov. 2 Journal of Neuroscience. Scientists knew that pupils get bigger when a person is paying attention. They also knew that paying attention can influence how people perceive the passage of time. Using monkeys, the new study links pupil size and timing directly. “What they’ve done here is connect those dots,” says neuroscientist Thalia Wheatley of Dartmouth College. More generally, the study shows how the eyes are windows into how the brain operates. “There’s so much information coming out of the eyes,” Wheatley says. Neuroscientist Masaki Tanaka of Hokkaido University School of Medicine in Japan and colleagues trained three Japanese macaques to look at a spot on a computer screen after precisely one second had elapsed. The study measured the monkeys’ subjective timing abilities: The monkeys had to rely on themselves to count the milliseconds. Just before each trial, the researchers measured pupil diameters. When the monkeys underestimated a second by looking too soon, their pupil sizes were slightly larger than in trials in which the monkeys overestimated a second, the researchers found. That means that when pupils were large, the monkeys felt time zoom by. But when pupils were small, time felt slower. |© Society for Science & the Public 2000 - 2016.
Link ID: 22818 - Posted: 11.02.2016
Nicola Davis The proficiency of elite football referees could be down to their eagle eyes, say researchers. A study of elite and sub-elite referees has found that a greater tendency to predict and watch contact zones between players contributes to the greater accuracy of top-level referees. “Over the years they develop so much experience that they now can anticipate, very well, future events so that they can already direct their attention to those pieces of information where they expect something to happen,” said lead author Werner Helsen from the University of Leuven. Keith Hackett, a former football referee and former general manager of the Professional Game Match Officials Limited, said the research chimed with his own experiences. “In working with elite referees for a number of years I have recognised their ability to see, recognise think and then act in a seamless manner,” he said. “They develop skill sets that enable them to see and this means good game-reading and cognitive skills to be in the right place at the right time.” Mistakes, he believes, often come down to poor visual perception. “Last week, we saw an elite referee fail to detect the violent act of [Moussa] Sissoko using his arm/elbow, putting his opponent’s safety at risk,” he said. “The review panel, having received confirmation from the referee that he failed to see the incident despite looking in the direction of the foul challenge, were able to act.” Writing in the journal Cognitive Research, researchers from the University of Leuven in Belgium and Brunel University in west London say they recruited 39 referees, 20 of whom were elite referees and 19 were experienced but had never refereed at a professional level. © 2016 Guardian News and Media Limited
Link ID: 22817 - Posted: 11.01.2016
By Jesse Singal For a long time, the United States’ justice system has been notorious for its proclivity for imprisoning children. Because of laws that grant prosecutors and judges discretion to bump juveniles up to the category of “adult” when they commit crimes deemed serious enough by the authorities, the U.S. is an outlier in locking up kids, with some youthful defendants even getting life sentences. Naturally, this has attracted a great deal of outrage and advocacy from human-rights organizations, who argue that kids, by virtue of not lacking certain judgment, foresight, and decision-making abilities, should be treated a bit more leniently. Writing for the Marshall Project and drawing on some interesting brain science, Dana Goldstein takes the argument about youth incarceration even further: We should also rethink our treatment of offenders who are young adults. As Goldstein explains, the more researchers study the brain, the more they realize that it takes decades for the organ to develop fully and to impart to its owners their full, adult capacities for reasoning. “Altogether,” she writes, “the research suggests that brain maturation continues into one’s twenties and even thirties.” Many of these insights come from the newest generation of neuroscience research. “Everyone has always known that there are behavioral changes throughout the lifespan,” Catherine Lebel, an assistant professor of radiology at the University of Calgary who has conducted research into brain development, told Goldstein. “It’s only with new imaging techniques over the last 15 years that we’ve been able to get at some of these more subtle changes.” ! © 2016, New York Media LLC.