Recent quotes:

Memories are strengthened via brainwaves produced during sleep, new study shows: Researchers use medical imaging to map areas involved in recalling learned information while we slumber -- ScienceDaily

The researchers found that during spindles of the learning night, the regions of the brain that were instrumental in processing faces were reactivated. They also observed that the regions in the brain involved in memory -- especially the hippocampus -- were more active during spindles in the subjects who remembered the task better after sleep. This reactivation during sleep spindles of the regions involved in learning and memory "falls in line with the theory that during sleep, you are strengthening memories by transferring information from the hippocampus to the regions of the cortex that are important for the consolidation of that specific type of information," he says.

Mathematical framework explores how the brain keeps a beat - Neuroscience News

Using neurobiological principles, the researchers built a mathematical model of a group of neurons that can cooperate to learn a musical beat from a rhythmic stimulus and keep the beat after the stimulus stops. The model demonstrates how a network of neurons could act as a “neuronal metronome” by accurately estimating time intervals between beats within tens of millisecond accuracy. This metronome relies on rhythmic brain activity patterns known as gamma oscillations to keep track of time.

Newborn babies have inbuilt ability to pick out words -- ScienceDaily

The researchers discovered two mechanisms in three-day-old infants, which give them the skills to pick out words in a stream of sounds. The first mechanism is known as prosody, the melody of language, allow us to recognise when a word starts and stops. The second is called the statistics of language, which describes how we compute the frequency of when sounds in a word come together. The discovery provides a key insight into a first step to learning language.

Brains of people with schizophrenia-related disorders aren't all the same: New study supports the use of a data-driven approach to identify novel biomarkers -- ScienceDaily

"We know that, on average, people with schizophrenia have more social impairment than people in the general population," says senior author Dr. Aristotle Voineskos in the Campbell Family Mental Health Research Institute at the Centre for Addiction and Mental Health (CAMH) in Toronto. "But we needed to take an agnostic approach and let the data tell us what the brain-behavioural profiles of our study participants looked like. It turned out that the relationship between brain function and social behaviour had nothing to do with conventional diagnostic categories in the DSM-5 (Diagnostic and Statistical Manual of Mental Disorders)." Most brain research in the mental health field compares a disease group to a non-disease or "healthy" group to search for biomarkers, a biological measure of mental health symptoms. This search for biomarkers has been elusive. This multi-site research study -- which included 179 participants recruited at CAMH in Toronto, Zucker Hillside Hospital in New York and the Maryland Psychiatric Research Center in Baltimore -- calls that paradigm into question because people with the same mental illness may not show the same biological patterns. The study, which involved participants completing a facial imitation task while undergoing functional MRI brain scans, found three "activation profiles," says first author Dr. Colin Hawco, also of CAMH. These can be described as typical, over-activated and de-activated profiles.

MRI technique shows unique signatures of concussion in rugby players -- ScienceDaily

The authors point out that there is growing evidence of persistent changes in the brain that last well beyond clinical recovery and clearance to return to play. This study confirmed those findings showing clear brain changes in both structure and function that persisted six-months after injury. They also showed that these persistent brain changes related to concussion history, even in healthy athletes. "We were able to show evidence of prior concussion history through this method," said Menon who is also a scientist at Robarts Research Institute and the director of the Western Centre for Functional and Metabolic Mapping. "This component correlates directly with the number of previous concussions that an athlete has had. This hasn't been shown before."

Ant Colonies Retain Memories That Outlast the Lifespans of Individuals | Science | Smithsonian

Colonies live for 20-30 years, the lifetime of the single queen who produces all the ants, but individual ants live at most a year. In response to perturbations, the behavior of older, larger colonies is more stable than that of younger ones. It is also more homeostatic: the larger the magnitude of the disturbance, the more likely older colonies were to focus on foraging than on responding to the hassles I had created; while, the worse it got, the more the younger colonies reacted. In short, older, larger colonies grow up to act more wisely than younger smaller ones, even though the older colony does not have older, wiser ants. Ants use the rate at which they meet and smell other ants, or the chemicals deposited by other ants, to decide what to do next. A neuron uses the rate at which it is stimulated by other neurons to decide whether to fire. In both cases, memory arises from changes in how ants or neurons connect and stimulate each other. It is likely that colony behavior matures because colony size changes the rates of interaction among ants. In an older, larger colony, each ant has more ants to meet than in a younger, smaller one, and the outcome is a more stable dynamic. Perhaps colonies remember a past disturbance because it shifted the location of ants, leading to new patterns of interaction, which might even reinforce the new behavior overnight while the colony is inactive, just as our own memories are consolidated during sleep. Changes in colony behavior due to past events are not the simple sum of ant memories, just as changes in what we remember, and what we say or do, are not a simple set of transformations, neuron by neuron. Instead, your memories are like an ant colony’s: no particular neuron remembers anything although your brain does.

Babies kicking in the womb are creating a map of their bodies -- ScienceDaily

The findings suggest that fetal kicks in the late stages of pregnancy -- the third trimester -- help to grow areas of the brain that deal with sensory input, and are how the baby develops a sense of their own body. The fast brainwaves evoked by the movement disappear by the time babies are a few weeks old. "Spontaneous movement and consequent feedback from the environment during the early developmental period are known to be necessary for proper brain mapping in animals such as rats. Here we showed that this may be true in humans too," explained study author Dr Lorenzo Fabrizi (UCL Neuroscience, Physiology & Pharmacology). Kimberley Whitehead (UCL Neuroscience, Physiology & Pharmacology) said: "We think the findings have implications for providing the optimal hospital environment for infants born early, so that they receive appropriate sensory input. For example, it is already routine for infants to be 'nested' in their cots -- this allows them to 'feel' a surface when their limbs kick, as if they were still inside the womb.

The Human Brain Is a Time Traveler - The New York Times

“What best distinguishes our species,” Seligman wrote in a Times Op-Ed with John Tierney, “is an ability that scientists are just beginning to appreciate: We contemplate the future.” He went on: “A more apt name for our species would be Homo prospectus, because we thrive by considering our prospects. The power of prospection is what makes us wise.”

The Human Brain Is a Time Traveler - The New York Times

In 2001, Randy Buckner’s adviser at Washington University, Marcus Raichle, coined a new term for the phenomenon: the “default-mode network,” or just “the default network.” The phrase stuck. Today, Google Scholar lists thousands of academic studies that have investigated the default network. “It looks to me like this is the most important discovery of cognitive neuroscience,” says the University of Pennsylvania psychologist Martin Seligman. The seemingly trivial activity of mind-wandering is now believed to play a central role in the brain’s “deep learning,” the mind’s sifting through past experiences, imagining future prospects and assessing them with emotional judgments: that flash of shame or pride or anxiety that each scenario elicits.

The Human Brain Is a Time Traveler - The New York Times

In her 1995 paper, Nancy Andreasen included two key observations that would grow in significance over the subsequent decades. When she interviewed the subjects afterward, they described their mental activity during the REST state as a kind of effortless shifting back and forth in time. “They think freely about a variety of things,” Andreasen wrote, “especially events of the past few days or future activities of the current or next several days.” Perhaps most intriguing, Andreasen noted that most of the REST activity took place in what are called the association cortices of the brain, the regions of the brain that are most pronounced in Homo sapiens compared with other primates and that are often the last to become fully operational as the human brain develops through adolescence and early adulthood. “Apparently, when the brain/mind thinks in a free and unencumbered fashion,” she wrote, “it uses its most human and complex parts.”

The Human Brain Is a Time Traveler - The New York Times

Andreasen’s background outside neuroscience might have helped her perceive the value lurking in the rest state, where her peers saw only trouble. As a professor of Renaissance literature, she published a scholarly appraisal of John Donne’s “conservative revolutionary” poetics. After switching fields in her 30s, she eventually began exploring the mystery of creativity through the lens of brain imaging. “Although neither a Freudian nor a psychoanalyst, I knew enough about human mental activity to quickly perceive what a foolish ‘control task’ rest was,” she would later write. “Most investigators made the convenient assumption that the brain would be blank or neutral during ‘rest.’ From introspection I knew that my own brain is often at its most active when I stretch out on a bed or sofa and close my eyes.”

Sometimes noise is the signal

“What happened is that we began putting people in scanners that can measure their brain activity,” Buckner recalls now, “and Mother Nature shouted back at us.” When people were told to sit and do nothing, the PET scans showed a distinct surge of mental energy in some regions. The resting state turned out to be more active than the active state. The odd blast of activity during the resting state would be observed in dozens of other studies using a similar control structure during this period. To this first generation of scientists using PET scans, the active rest state was viewed, in Buckner’s words, as “a confound, as troublesome.” A confound is an errant variable that prevents a scientist from doing a proper control study. It’s noise, mere interference getting in the way of the signal that science is looking for. Buckner and his colleagues noted the strange activity in a paper submitted in 1993, but almost as an afterthought, or an apology.

Could consciousness all come down to the way things vibrate?

Gamma waves are associated with large-scale coordinated activities like perception, meditation or focused consciousness; beta with maximum brain activity or arousal; and theta with relaxation or daydreaming. These three wave types work together to produce, or at least facilitate, various types of human consciousness, according to Fries. But the exact relationship between electrical brain waves and consciousness is still very much up for debate. Fries calls his concept “communication through coherence.” For him, it’s all about neuronal synchronization. Synchronization, in terms of shared electrical oscillation rates, allows for smooth communication between neurons and groups of neurons. Without this kind of synchronized coherence, inputs arrive at random phases of the neuron excitability cycle and are ineffective, or at least much less effective, in communication.

Traumatic brain injuries can lead to long-term neurological and psychiatric disorders -- ScienceDaily

Researchers examined how injuries affected children up to five years later. They found that only 59 percent of children with traumatic brain injury could expect to be symptom-free in 5 years, versus 80 percent of those with orthopedic injuries.

New target of alcohol in the brain -- ScienceDaily

"The KCNK13 channel is absolutely required for alcohol to stimulate the release of dopamine by these neurons," said Mark Brodie, professor of physiology and biophysics in the UIC College of Medicine and lead author of the study. "Without the channel, alcohol can't stimulate the release of dopamine, and so drinking is likely less rewarding. We think that the KCNK13 channel presents an extremely exciting new target for drugs that could potentially help people with alcohol use disorder to stop drinking."

Brain cells called astrocytes have unexpected role in brain 'plasticity': Researchers show protein made by astrocytes enables the brain's maturation and regulates its flexibility -- ScienceDaily

The signal turned out to be a protein astrocytes secrete called Chrdl1, which increases the number and maturity of connections between nerve cells, enabling the stabilization of neural connections and circuits once they finish developing. To further understand the role of Chrdl1, the team developed mouse models with the gene disabled by introduced mutations. These mice had a level of plasticity in their brains that was much higher than normal. Adult mice with the Chrdl1 mutation had brain plasticity that looked very much like that of young mice, whose brains are still in early stages of development.

Time-traveling illusion tricks the brain: How the brain retroactively makes sense of rapid auditory and visual sensory stimulation -- ScienceDaily

The first illusion is called the Illusory Rabbit. To produce the illusion, first a short beep and a quick flash are played nearly simultaneously on a computer, with the flash appearing at the left side of the screen. Next, 58 milliseconds after the first beep, a lone beep is played. Finally, 58 milliseconds after the second beep, a second nearly simultaneous beep-flash pair occurs, but with the flash appearing on the right side of the screen. The beep location is always central and does not move. Though only two flashes are played, most people viewing the illusion perceive three flashes, with an illusory flash coinciding with the second beep and appearing to be located in the center of the screen. The fact that the illusory flash is perceived in between the left and right flashes is the key evidence that the brain is using postdictive processing. "When the final beep-flash pair is later presented, the brain assumes that it must have missed the flash associated with the unpaired beep and quite literally makes up the fact that there must have been a second flash that it missed," explains Stiles. "This already implies a postdictive mechanism at work. But even more importantly, the only way that you could perceive the shifted illusory flash would be if the information that comes later in time -- the final beep-flash combination -- is being used to reconstruct the most likely location of the illusory flash as well."

Resynchronizing Neurons to Erase Schizophrenia - Neuroscience News

he Geneva neuroscientists chose to focus on neural networks of the hippocampus, a brain structure notably involved in memory. They studied a mouse model that reproduces the genetic alteration of DiGeorge syndrome as well as some behavioural changes associated with schizophrenia. In the hippocampus of a control mouse, the thousands of neurons that make up the network coordinate according to a very precise sequence of activity, which is dynamic in time and synchronized. However, in the neural networks of their mouse models, the scientists observed something completely different: the neurons showed the same level of activity as in control animals, but without any coordination, as if these cells were incapable of communicating properly with each other. “The organization and synchronization of neural networks is achieved through the intervention of subpopulations of inhibitory neurons, including parvalbumin neurons,» says Carleton. “However, in this animal model of schizophrenia, these neurons are much less active. Without proper inhibition to control and structure the electrical activity of other neurons in the network, anarchy rules. ”

How attention orchestrates groups of nerve cells to enrich the brain's symphony -- ScienceDaily

Silence in the concert hall. The conductor raises the baton and the strings begin. They play the first four bars of Mozart's "A Little Night Music." All together they play a single melody, which is probably one of the best known in the music world. Then the voices divide. Different string instruments play separate melodies and the "Little Night Music" thus becomes a complex work of art. Scientists from the German Primate Center (DPZ) -- Leibniz Institute for Primate Research in Göttingen and Institute for Research in Fundamental Sciences in Tehran, Iran, recently discovered in a study with rhesus monkeys that nerve cells assume the role of musicians in visual perception in our brain. Usually many cells are active together (synchronously) when they process simple stimuli from our environment. The researchers were able to show that visual attention desynchronizes these nerve cells' activity and thus enables more complex information processing. Such insights into the neural mechanisms of attention in the healthy state may provide evidence of mechanisms underlying neuronal diseases such as attention deficit hyperactivity disorder (ADHD) or autism (BMC Biology).

Great minds may think alike, but all minds look alike -- ScienceDaily

The (skeleton) structure of the brain is like a road map consisting of many narrow streets (i.e., weak links), and a small fraction of highways each containing thousands of lanes (i.e., very strong links). Such a diverse road map could either be a spontaneous outcome of a random brain activity, or alternatively could be directed by a meaningful learning activity, where the "highways" direct the information flow in the brain. "A byproduct of dendritic learning is the wide spectrum of link strengths. The dendritic learning enables us to offer an explanation for an additional universal phenomenon observed in all brains and indicates its important role," said Prof. Kanter, whose research team includes Herut Uzan, Shira Sardi, Amir Goldental and Roni Vardi. The underlying mechanism is a fast response of a neuron to its strong entry compared to a slow response to a weak one. "The mechanism is similar to a pool filled through a wide pipe or through a narrow one. The wide pipe fills the pool faster," explained the research team.

The spotlight of attention is more like a strobe light -- ScienceDaily

"Our subjective experience of the visual world is an illusion," said Sabine Kastner, a professor of psychology and the Princeton Neuroscience Institute (PNI). "Perception is discontinuous, going rhythmically through short time windows when we can perceive more or less." The researchers use different metaphors to describe this throb of attention, including a spotlight that waxes and wanes in its intensity. Four times per second -- once every 250 milliseconds -- the spotlight dims and the house lights come up. Instead of focusing on the action "onstage," your brain takes in everything else around you, say the scientists. Their work appears as a set of back-to-back papers in in the Aug. 22 issue of Neuron; one paper focuses on human research subjects, the other on macaque monkeys. "The question is: How can something that varies in time support our seemingly continuous perception of the world?" said Berkeley's Randolph Helfrich, first author on the human-focused paper. "There are only two options: Is the data wrong, or is our understanding of our perception biased? Our research shows that it's the latter. Our brains fuse our perceptions into a coherent movie -- we don't experience the gaps."

Why Sitting May Be Bad for Your Brain - The New York Times

It was equally apparent when people broke up their sitting after two hours, although blood flow rose during the actual walking break. It soon sank again, the ultrasound probes showed, and was lower at the end of that session than at its start. But brain blood flow rose slightly when the four hours included frequent, two-minute walking breaks, the scientists found. Interestingly, none of these changes in brain blood flow were dictated by alterations in breathing and carbon dioxide levels, the scientists also determined. Carbon dioxide levels had remained steady before and after each session.

Study of Retired NFL and NHL Players Doesn't Find Evidence of Early Onset Dementia - Neuroscience News

The assessments of cognitive function (e.g., memory, attention, visual spatial orientation), executive function and mental health in the retired athletes didn’t reveal statistically significant impairment compared to controls. The researchers did find evidence of mild cognitive impairment (MCI) in more of the retired athletes than the controls, but said the rate was as expected for the age, education level and body mass index of the athletes, all factors that can raise the risk of MCI; it also was not statistically significant. Advanced brain imaging detected no microscopic or macroscopic brain tissue injury differences in retired athletes versus the controls. The non-contact sport athletes were found to have a higher rate of microbleeds in the brain but these results only approached statistical significance.

We may have less control over our thoughts than previously assumed -- ScienceDaily

Morsella and the other researchers conducted two experiments with SF State students. In the first experiment, 35 students were told beforehand to not count an array of objects presented to them. In 90 percent of the trials, students counted the objects involuntarily. In a second experiment, students were presented with differently colored geometric shapes and given the option of either naming the colors (one set) or counting the shapes (a different set). Even though students chose one over the other, around 40 percent thought about both sets. "The data support the view that, when one is performing a desired action, conscious thoughts about alternative plans still occupy the mind, often insuppressibly," said Morsella. Understanding how sets work could have implications for the way we absorb information -- and whether we choose to act or not. We think of our conscious minds as private and insulated from the outside world, says Morsella. Yet our "insulation" may be more permeable than we think. "Our conscious mind is the totality of our experience, a kind of 'prime real estate' in the cognitive apparatus, influencing both decision-making and action," Morsella said. The new study demonstrates that it's actually quite easy to activate sets in people and influence what occupies the brain's "prime real estate." "The research shows that stimuli in the environment are very important in determining what we end up thinking about and that once an action plan is strongly activated its many effects can be difficult to override," said Morsella.

Evidence Rebuts Chomsky's Theory of Language Learning - Scientific American

The research suggests a radically different view, in which learning of a child’s first language does not rely on an innate grammar module. Instead the new research shows that young children use various types of thinking that may not be specific to language at all—such as the ability to classify the world into categories (people or objects, for instance) and to understand the relations among things. These capabilities, coupled with a unique human ability to grasp what others intend to communicate, allow language to happen. The new findings indicate that if researchers truly want to understand how children, and others, learn languages, they need to look outside of Chomsky’s theory for guidance.

Fundamental Rule of Brain Plasticity Discovered - Neuroscience News

Our brains are famously flexible, or “plastic,” because neurons can do new things by forging new or stronger connections with other neurons. But if some connections strengthen, neuroscientists have reasoned, neurons must compensate lest they become overwhelmed with input. In a new study in Science, researchers at the Picower Institute for Learning and Memory at MIT demonstrate for the first time how this balance is struck: when one connection, called a synapse, strengthens, immediately neighboring synapses weaken based on the action of a crucial protein called Arc. Senior author Mriganka Sur said he was excited but not surprised that his team discovered a simple, fundamental rule at the core of such a complex system as the brain, where 100 billion neurons each have thousands of ever-changing synapses. He likens it to how a massive school of fish can suddenly change direction, en masse, so long as the lead fish turns and every other fish obeys the simple rule of following the fish right in front of it.