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Perception of musical pitch varies across cultures: How people interpret musical notes depends on the types of music they have listened to -- ScienceDaily

This question has been hard to answer, in part because of the difficulty in finding people who have not been exposed to Western music. Now, a new study led by researchers from MIT and the Max Planck Institute for Empirical Aesthetics has found that unlike residents of the United States, people living in a remote area of the Bolivian rainforest usually do not perceive the similarities between two versions of the same note played at different registers (high or low). The findings suggest that although there is a natural mathematical relationship between the frequencies of every "C," no matter what octave it's played in, the brain only becomes attuned to those similarities after hearing music based on octaves, says Josh McDermott, an associate professor in MIT's Department of Brain and Cognitive Sciences.

Sunflowers found to share nutrient-rich soil with others of their kind

In the first study, the researchers placed isolated sunflower plants near a rich food source and watched how it behaved. As expected, the plant sent more roots into the area, allowing it to consume more nutrients. But they also found that when they placed two sunflower plants an equal distance from the same food source, both sent fewer roots than they would have were they alone. This was a clear sign that the plants were not only aware of the presence of the other, but were working together to allow both of them to gain the greatest benefit. In another experiment, the researchers placed sunflower plants at different distances from the rich soil patch and found that the sunflower nearest the soil patch sent out just as many new roots as if it were isolated. In other experiments, the researchers planted multiple plants at different distances from the nutrient-rich patch to see how they would respond. They report that plants that were growing with a neighbor actually decreased root length in such shared patches—and they did not increase them when they were close to very high-quality soil areas. The researchers conclude that sunflowers work together to gain the most benefit from the soil for themselves and for those around them.

Brain waves detected in mini-brains grown in a dish -- ScienceDaily

The pea-sized brains, called cerebral organoids, are derived from human pluripotent stem cells. By putting them in culture that mimics the environment of brain development, the stem cells differentiate into different types of brain cells and self-organize into a 3D structure resembling the developing human brain. Scientists have successfully grown organoids with cellular structures similar to those of human brains. However, none of the previous models developed human-like functional neural networks. Networks appear when neurons are mature and become interconnected, and they are essential for most brain activities. "You can use brain organoids for several things, including understand normal human neurodevelopment, disease modeling, brain evolution, drug screening, and even to inform artificial intelligence," Muotri says. Muotri and colleagues designed a better procedure to grow stem cells, including optimizing the culture medium formula. These adjustments allowed their organoids to become more mature than previous models. The team grew hundreds of organoids for 10 months and used multi-electrode arrays to monitor their neural activities. The team began to detect bursts of brain waves from organoids at about two months. The signals were sparse and had the same frequency, a pattern seen in very immature human brains. As the organoids continued to grow, they produced brain waves at different frequencies, and the signals appeared more regularly. This suggests the organoids have further developed their neural networks.

Neuroscientists discover neuron type that acts as brain's metronome: By keeping the brain in sync, these long-hypothesized but never-found neurons help rodents to detect subtle sensations -- ScienceDaily

This type of neuron spikes rhythmically, and in a synchronized manner, independent of external sensations, said Chris Moore, a professor of neuroscience at Brown and the associate director of the Carney Institute for Brain Science. By "setting the beat," the neurons appear to improve rodents' ability to detect when their whiskers are lightly tapped. Brain waves with approximately 40 cycles per second -- also known as gamma rhythms -- have been studied since the mid-1930s in humans and rodents, and earlier work from Moore's lab showed that boosting the rodents' natural gamma rhythms helped the rodents detect fainter whisker sensations. "Gamma rhythms have been a huge topic of debate," Moore said. "Some greatly respected neuroscientists view gamma rhythms as the magic, unifying clock that align signals across brain areas. There are other equally respected neuroscientists that, colorfully, view gamma rhythms as the exhaust fumes of computation: They show up when the engine is running but they're absolutely not important." The metronome-like function of the gamma rhythm has been hypothesized before, but has been largely written off because gamma rhythms change in response to sensations, Moore added. These newly discovered spiking "metronome" neurons -- which spike around 40 cycles a second -- do not.

Decentralizing science may lead to more reliable results in biomedical research: Analysis of data on tens of thousands of drug-gene interactions -- ScienceDaily

"The way science is often produced may inadvertently contribute to unreliable results," says senior author James Evans, Professor of Sociology at the University of Chicago, and External Professor at the Santa Fe Institute, US. "For example, a large group of scientists who frequently collaborate, use similar methods, share equipment, and frequently cite similar works are prone to producing the same, self-confirming results. Although such a group may produce repeated published experiments, our results demonstrate that their findings are not independent. Independent labs perform experiments in different ways with different expectations and are less prone to peer pressure than a densely connected networks of scientists."

How arousal impacts physiological synchrony in relationships -- ScienceDaily

The findings show that sharing similar amounts of sympathetic arousal was sufficient to increase perceptions of similarity -- a precursor to friendship -- regardless of social context and no matter the arousal levels partners shared. One possible explanation for this finding is that patterns of sympathetic arousal may correlate with observable body movements (and by extension a lack of arousal may correlate with a lack of body movement) that might predict perceived similarity if shared among partners. By comparison, people for whom parasympathetic synchrony and parasympathetic reactivity was high generally reported more friendship interest when the social context permitted conversation than when it did not. In other words, when parasympathetic activity increased during a social interaction, parasympathetic synchrony only mattered for the development of friendship between strangers who could converse.

When Do We Fall in Neural Synchrony With Others?

Compared to dyads between real participants and confederates, real-participant pairings showed greater cooperation behavior and IBS between bilateral dorsolateral prefrontal cortex. And, IBS and cooperation increased over time in real-participant pairings, whereas they remained low and constant in dyads with the confederate. These findings indicate that IBS occurs between individuals engaging in interpersonal interaction during a collaborative task, during which both IBS and cooperatively interpersonal interaction tend to increase over time.

Why visual stimulation may work in fight against Alzheimer's: Mouse study - Neuroscience News

Tsai’s original study on the effects of flickering light showed that visual stimulation at a frequency of 40 hertz (cycles per second) induces brain waves known as gamma oscillations in the visual cortex. These brain waves are believed to contribute to normal brain functions such as attention and memory, and previous studies have suggested that they are impaired in Alzheimer’s patients. Tsai and her colleagues later found that combining the flickering light with sound stimuli — 40-hertz tones — reduced plaques even further and also had farther-reaching effects, extending to the hippocampus and parts of the prefrontal cortex. The researchers have also found cognitive benefits from both the light- and sound-induced gamma oscillations. In their new study, the researchers wanted to delve deeper into how these beneficial effects arise. They focused on two different strains of mice that are genetically programmed to develop Alzheimer’s symptoms. One, known as Tau P301S, has a mutated version of the Tau protein, which forms neurofibrillary tangles like those seen in Alzheimer’s patients. The other, known as CK-p25, can be induced to produce a protein called p25, which causes severe neurodegeneration. Both of these models show much greater neuron loss than the model they used for the original light flickering study, Tsai says. The researchers found that visual stimulation, given one hour a day for three to six weeks, had dramatic effects on neuron degeneration. They started the treatments shortly before degeneration would have been expected to begin, in both types of Alzheimer’s models. After three weeks of treatment, Tau P301S mice showed no neuronal degeneration, while the untreated Tau P301S mice had lost 15 to 20 percent of their neurons. Neurodegeneration was also prevented in the CK-p25 mice, which were treated for six weeks.

Finding the 'Goldilocks' level of enthusiasm for business pitches -- ScienceDaily

They found that, generally speaking, the higher the peak level of enthusiasm, the more likely the entrepreneur was to receive funding, after controlling for differences in the products and business ideas. But there was a bell curve in the results, where the likelihood of funding tended to fall as "peak joy" levels went on for too long. "Although a higher level of peak joy displayed by entrepreneurs during their pitches leads to better funding performance over time, prolonged display of peak joy seemed to undermine funding performance," Liu said. "Another possible interpretation is that investors may believe the entrepreneur is acting and the pitch is manipulative. Maybe they feel the entrepreneur is using his or her excitement to manipulate the investors' perceptions in hopes of increasing the odds of getting funding."

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.

Dead zones in circadian clocks -- ScienceDaily

One of the important properties of circadian clocks is the response to light signals, which enables organisms to become entrained to the 24-hour light-dark cycle on Earth. It has been shown that circadian clocks respond to light signals during the night, whereas they do not respond to such signals during the daytime. This holds true even when an organism is kept in complete darkness; a short light pulse does not change the time of the circadian clock when body time of the individual is at daytime. The time period in which the circadian clock is insensitive to light signals is referred to as the "dead zone." Previous studies have indicated that the presence of a dead zone improves the robustness of the clock. However, the mechanism underlying its generation is unclear.

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.

Good Vibes Are Contagious | Outside Online

even below-the-surface emotions, such as motivation, are contagious. If someone is working in the same room with people who are internally driven, their attitude also improves. If, however, someone is working in the same room with those who aren’t too excited about their work, then their motivation decreases. A 2017 study out of Northwestern University found that sitting within 25 feet of a high performer at work improved an employee’s performance by 15 percent. But sitting within 25 feet of a low performer hurt their performance by 30 percent. That’s an enormous effect!

Fireflies, Heart Beats, and the Science of Sync – Neuroscience News

“The perplexing feature of these particular states is that the Rockettes in our metaphor can only see their nearest neighbor, yet manage to be coordinating with their neighbor’s neighbor,” says lead author Matthew Matheny, a research scientist at Caltech and member of the Kavli Nanoscience Institute. “We didn’t know what we were going to see,” says Matheny. “But what these experiments are telling us is that you can get complexity out of a very simple system. This was something that was hinted at before but not shown experimentally until now.” “These exotic states arising from a simple system are what we call emergent,” says Roukes. “The whole is greater than the sum of the parts.”

Fireflies, Heart Beats, and the Science of Sync – Neuroscience News

But it has also been observed since the early 2000s that these networks, even when consisting of identical oscillators, can spontaneously flip out of sync and evolve into complex patterns. To better understand what is going on, Roukes and colleagues began to develop networks of oscillating nanomechanical devices. They started by just connecting two, and now, in the new study, have developed an interconnected system of eight. To the team’s surprise, the eight-node system spontaneously evolved into various exotic, complex states. “This is the first experimental demonstration that these many distinct, complex states can occur in the same simple system,” says co-author James Crutchfield, a visiting associate in physics at Caltech and a professor of physics at UC Davis.

Applying a network perspective to human physiology: Physicist describes 'network physiology,' which looks at different organ systems and how they relate to each other -- ScienceDaily

"We need to show how the different systems communicate with each other and adjust, coordinate and stay in sync," said Ivanov. The human body, according to this view, can be thought of as a network, with each organ serving as a node connected to other organs and other nodes. "The nodes are not just dots," he said. "They're dynamical systems, constantly changing in time, as are the connections between them." Today's best hospitals aren't equipped to monitor the inter-organ interactions. "Separate devices keep track of separate functions, but no single monitor can observe a multitude of functions," he said. To improve health monitoring techniques, Ivanov and his colleagues have spent the past decade developing the computational tools and biomedical devices needed to capture data streams from different organ systems and see how they relate to each other.

Fat cells work different 'shifts' throughout the day -- ScienceDaily

During this unique study seven participants underwent regulated sleep-wake cycles and meal times before entering the laboratory, where they maintained this routine for a further three days. Participants then experienced a 37- hour 'constant routine' during which time they did not experience daily changes in light-dark, feed-fast and sleep-wake cycles. Biopsies of fat tissue were taken at six hourly intervals and then followed by an analysis of gene expression. Researchers identified 727 genes in the fat tissue that express their own circadian rhythm, many carrying out key metabolic functions. A clear separation in gene rhythms was identified with approximately a third peaking in the morning and two thirds in the evening.

Exercise in Morning or Afternoon to Shift Your Body Clock Forward – Neuroscience News

This study found that exercising at 7 am or between 1 and 4 pm advanced the body clock to an earlier time, and exercising between 7 and10 pm delayed the body clock to a later time. Exercising between 1 and 4 am and at 10 am, however, had little effect on the body clock, and the phase-shifting effects of exercise did not differ based on age nor gender.

The music of conversing

He knew an Irish composer who lived in Paris and who noticed a pattern at his local boulangerie. Customers who said “Bonjour!” in an ascending line, with two notes a sixth apart, got served first. English has similar patterns, studies have found. We use minor thirds when telling sad stories and major thirds when telling happy ones. We match pitches with those we admire and expect the same of those who admire us. We harmonize when we agree—starting our sentences a perfect fifth or an octave from where the last sentence left off—and grow dissonant when we disagree. Our arguments are full of tritones. Whether we know it or not, Wells said, we’re always singing.

Roomful of Teeth Is Revolutionizing Choral Music | The New Yorker

Christian monks sang in unison for nearly a thousand years before they allowed themselves a second vocal line, and then only in lockstep with the melody. Three-part harmony had to wait another three centuries, when English and French clergymen added a third or a sixth to the chord. And what we think of as classical harmony, with major and minor keys and chords that follow the bass line, didn’t emerge until the Renaissance. As late as the seventeen-hundreds, the tritone—a dissonant interval of two notes, three whole steps apart—was reviled as diabolus in musica: the devil in music.

The unexpected creates reward when listening to music: Scientists prove difference between expected/actual outcomes cause reward response -- ScienceDaily

Using an algorithm, the researchers then determined the reward prediction error for each choice -- the difference between an expected reward and the actual reward received. They compared that data to the MRI data, and found that reward prediction errors correlated with activity in the nucleus accumbens, a brain region that in previous studies has been shown to activate when the subject is experiencing musical pleasure. This is the first evidence that musically elicited reward prediction errors cause musical pleasure. It is also the first time an aesthetic reward such as music has been shown to create such a response. Previous studies have focused on more tangible rewards such as food or money. Subjects whose reward prediction errors most closely matched activity in the nucleus accumbens also showed the most progress in learning the choices that led to the consonant tones. This establishes music as a neurobiological reward capable of motivating learning, showing how an abstract stimulus can engage the brain's reward system to potentially pleasurable effect and motivate us to listen again and again.

Brain clock ticks differently in autism -- ScienceDaily

Sensory areas of the brain that receive input from the eyes, skin and muscles usually have shorter processing periods compared with higher-order areas that integrate information and control memory and decision-making. The new study, published in the journal eLife on February 5, shows that this hierarchy of intrinsic neural timescales is disrupted in autism. Atypical information processing in the brain is thought to underlie the repetitive behaviors and socio-communicational difficulties seen across the spectrum of autistic neurodevelopmental disorders (ASD), but this is one of the first indications that small-scale temporal dynamics could have an outsized effect.

Mathematical monotsukuri: Summing a constant may help to detect synchronized brain activity -- ScienceDaily

Humans are good at detecting whether separate things happen simultaneously, for example, if two lights flash together or not. When two swings move with a regular motion, it is easy to tell whether there is any temporal relationship or "synchronization." However, the trajectory of some objects, such as kites, can be very complicated but still exhibit some pattern, even though our eyes may fail to follow it; such systems are called "chaotic." In physics, chaos does not mean lack of order; it indicates the presence of a very complicated type of order. Such situations can be found across very different scenarios, including the activity of neurons. When trajectories, which do not necessarily correspond to physical movement and can instead represent electrical signals, are sufficiently complicated, it becomes challenging to determine if they are synchronized. In many cases, only some aspects of their motion might be interrelated. Hence, measuring synchronization is difficult and has been the subject of research for decades.

Collaborative video games could increase office productivity: Team video gaming increased effectiveness of newly-formed teams by 20 percent -- ScienceDaily

A new study by four BYU information systems professors found newly-formed work teams experienced a 20 percent increase in productivity on subsequent tasks after playing video games together for just 45 minutes. The study, published in AIS Transactions on Human-Computer Interaction, adds to a growing body of literature finding positive outcomes of team video gaming. "To see that big of a jump -- especially for the amount of time they played -- was a little shocking," said co-author and BYU associate professor Greg Anderson. "Companies are spending thousands and thousands of dollars on team-building activities, and I'm thinking, go buy an Xbox."

Near bottom: focus triggered by new activity or movement?

Research has shown that the electrical activity of the neocortex of the brain changes, when we focus our attention. Neurons stop signalling in sync with one another and start firing out of sync. This is helpful, says Williams, because it allows individual neurons to respond to sensory information in different ways. Thus, you can focus on a car speeding down the road or on what a friend is saying in a crowded room. It's known that the cholinergic system in the brain plays an important role in triggering this desynchronization. The cholinergic system consists of clusters of special neurons that synthesise and release a signalling molecule called acetylcholine, he explains, and these clusters make far reaching connections throughout the brain. Not only does this cholinergic system act like a master switch, but mounting evidence suggests it also enables the brain to identify which sensory input is the most salient -- i.e. worthy of attention -- at any given moment and then shine a spotlight on that input. "The cholinergic system broadcasts to the brain, 'this thing is really important to be vigilant to'," says Williams. He adds that the cholinergic system has been proposed to have a far-reaching impact on our cognitive abilities. "Destruction of the cholinergic system in animals profoundly degrades cognition, and the formation of memory," he says. "Importantly, in humans a progressive degeneration of the cholinergic system occurs in devastating diseases that blunt cognition and memory, such as Alzheimer's disease." But precisely which neurons in the cortex are being targeted by this master switch and how it's able to influence their function was unknown. Williams and QBI researcher Lee Fletcher wondered if layer 5 B-pyramidal neurons, the 'output' neurons of the neocortex, might be involved, because they are intimately involved in how we perceive the world. "The output neurons of the neocortex perform computations that are thought to underlie our perception of the world," says Williams. Williams and Fletcher wanted to know if the cholinergic system is able to influence the activity of these output neurons. Using a technique called optogenetics, they modified neurons in the cholinergic system in the brains of mice so that they could be activated with a flash of blue light, triggering a sudden release of acetylcholine. This allowed the researchers to closely monitor the interaction between the cholinergic system and the output neurons. They discovered that if the output neurons were not currently active, not much happened. But when those neurons received excitatory input to their dendrites, the cholinergic system was able to massively increase their activity. "It's as if the cholinergic system has given a 'go' signal," says Fletcher, enabling the output neurons of the neocortex to powerfully respond. Importantly, this change was selective, and only apparent when excitatory input was being processed in the dendrites of the 'output' neurons. "We have known for some time that the dendrites of the output neurons of the neocortex only become active when animals are actively performing a behaviour, and that this activity is correlated with perception and task performance," says Williams. This new work demonstrates that the cholinergic system is critical to this transition in mice and rats, allowing the output neurons to perform computations in a state-dependent manner. "We suggest that this switch also occurs in the human neocortex, allowing us to rapidly switch our state of vigilance and attention," says Williams. "Our work therefore provides important insight into how the progressive degeneration of the cholinergic system in disease blunts human cognition."

Synchronizing Gait with Cardiac Cycle Phase Alters Heart Rat... : Medicine & Science in Sports & Exercise

Finally, if diastolic stepping is truly advantageous for exercise performance, we wondered if there is any natural tendency for elite runners to step diastolically without prompting. We observed that 3 of the 10 subjects stepped accurately at the diastolic target timing (45% ± 15% RRI) during a substantial portion of their final, unprompted (silent) control period (e.g., see Fig. 2B). In one of those cases, the subject was guided to systolic step timing during the final prompted period but naturally reverted to stepping during diastole when the auditory prompt was removed. By comparison, none of the subjects stepped at a consistent systolic phase during the free stepping control stages. These anecdotal observations are also consistent with the findings of earlier authors, including Niizeki (10), which suggested that the heart automatically adjusts its timing, when HR = SR, to prevent ventricular systole from coinciding with maximal peripheral skeletal muscle contraction.