Posts tagged brain activity
Articles and news from the latest research reports.
When we watch a movie, our brains react to it immediately in a way similar to other people’s brains.
Researchers at Aalto University in Finland have succeeded in developing a method fast enough to observe immediate changes in the function of the brain even when watching a movie. By employing movies it was possible to investigate the function of the human brain in experimental conditions that are close to natural. Traditionally, in neuroscience research, simple stimuli, such as checkerboard patterns or single images, have been used.
Viewing a movie creates multilevel changes in the brain function. Despite the complexity of the stimulus, the elicited brain activity patterns show remarkable similarities across different people – even at the time scale of fractions of seconds.
The analysis revealed important similarities between brain signals of different people during movie viewing. These similar kinds or synchronized signals were found in brain areas that are connected with the early-stage processing of visual stimuli, detection of movement and persons, motor coordination and cognitive functions. The results imply that the contents of the movie affected certain brain functions of the subjects in a similar manner, explains Kaisu Lankinen the findings of her doctoral research.
So far, studies in this field have mainly been based on functional magnetic resonance imaging (fMRI). However, given the superior temporal resolution, within milliseconds, magnetoencephalography (MEG) is able to provide more complete picture of the fast brain processes. With the help of MEG and new analysis methods, investigation of significantly faster brain processes is possible and it enables detection of brain activity in frequencies higher than before.
In the novel analysis, brain imaging was combined with machine-learning methodology, with which signals of a similar form were mined from the brain data.
The research result was recently published in the NeuroImage journal.
Yale researchers reconstruct facial images locked in a viewer’s mind
Using only data from an fMRI scan, researchers led by a Yale University undergraduate have accurately reconstructed images of human faces as viewed by other people.
“It is a form of mind reading,” said Marvin Chun, professor of psychology, cognitive science and neurobiology and an author of the paper in the journal Neuroimage.
The increased level of sophistication of fMRI scans has already enabled scientists to use data from brain scans taken as individuals view scenes and predict whether a subject was, for instance, viewing a beach or city scene, an animal or a building.
“But they can only tell you they are viewing an animal or a building, not what animal or building,” Chun said. “This is a different level of sophistication.”
One of Chun’s students, Alan S. Cowen, then a Yale junior now pursing an advanced degree at the University of California at Berkeley, wanted to know whether it would be possible to reconstruct a human face from patterns of brain activity. The task was daunting, because faces are more similar to each other than buildings. Also large areas of the brain are recruited in the processing of human faces, a testament to its importance in survival.
“We perceive faces in a much greater level of detail than we perceive other things,” Cowen said.
Working with funding from the Yale Provost’s office, Cowen and post doctoral researcher Brice Kuhl, now an assistant professor at New York University, showed six subjects 300 different “training” faces while undergoing fMRI scans. They used the data to create a sort of statistical library of how those brains responded to individual faces. They then showed the six subjects new sets of faces while they were undergoing scans. Taking that fMRI data alone, researchers used their statistical library to reconstruct the faces their subjects were viewing.
Cowen said the accuracy of these facial reconstructions will increase with time and he envisions they can be used as a research tool, for instance in studying how autistic children respond to faces.
Chun said the study shows the value of funding research ambitions of Yale undergraduates.
“I would never have received external funding for this, it was too novel,” Chun said.
![EEG study: Brain infers structure, rules of tasks
A new study documents the brain activity underlying our strong tendency to infer a structure of context and rules when learning new tasks (even when a structure isn’t valid). The findings, which revealed individual differences, shows how we try to apply task knowledge to similar situations and could inform future research on learning disabilities.
In life, many tasks have a context that dictates the right actions, so when people learn to do something new, they’ll often infer cues of context and rules. In a new study, Brown University brain scientists took advantage of that tendency to track the emergence of such rule structures in the frontal cortex — even when such structure was not necessary or even helpful to learn — and to predict from EEG readings how people would apply them to learn new tasks speedily.
Context and rule structures are everywhere. They allow an iPhone user who switches to an Android phone, for example, to reason that dimming the screen would involve finding a “settings” icon that will probably lead to a slider control for “brightness.” But when the context changes, inflexible generalization can lead a person temporarily astray — like a small-town tourist who greets strangers on the streets of New York City. In some developmental learning disabilities, the whole process of inferring abstract structures may be impaired.
“The world tends to be organized, and so we probably develop prior [notions] over time that there is going to be a structure,” said Anne Collins, a postdoctoral scholar in the Department of Cognitive, Linguistic, and Psychological Sciences at Brown and lead author of the study published March 25 in the Journal of Neuroscience. “When the world is organized, you just reduce the size of what you have to learn about by being able to generalize across situations in which the same things usually happen together. It is efficient to generalize if there is structure, and there usually is structure.”
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EEG study: Brain infers structure, rules of tasks
A new study documents the brain activity underlying our strong tendency to infer a structure of context and rules when learning new tasks (even when a structure isn’t valid). The findings, which revealed individual differences, shows how we try to apply task knowledge to similar situations and could inform future research on learning disabilities.
In life, many tasks have a context that dictates the right actions, so when people learn to do something new, they’ll often infer cues of context and rules. In a new study, Brown University brain scientists took advantage of that tendency to track the emergence of such rule structures in the frontal cortex — even when such structure was not necessary or even helpful to learn — and to predict from EEG readings how people would apply them to learn new tasks speedily.
Context and rule structures are everywhere. They allow an iPhone user who switches to an Android phone, for example, to reason that dimming the screen would involve finding a “settings” icon that will probably lead to a slider control for “brightness.” But when the context changes, inflexible generalization can lead a person temporarily astray — like a small-town tourist who greets strangers on the streets of New York City. In some developmental learning disabilities, the whole process of inferring abstract structures may be impaired.
“The world tends to be organized, and so we probably develop prior [notions] over time that there is going to be a structure,” said Anne Collins, a postdoctoral scholar in the Department of Cognitive, Linguistic, and Psychological Sciences at Brown and lead author of the study published March 25 in the Journal of Neuroscience. “When the world is organized, you just reduce the size of what you have to learn about by being able to generalize across situations in which the same things usually happen together. It is efficient to generalize if there is structure, and there usually is structure.”
The Hidden Dangers of Going Under
Anesthesia may have lingering side effects on the brain, even years after an operation
Two and a half years ago Susan Baker spent three hours under general anesthesia as surgeons fused several vertebrae in her spine. Everything went smoothly, and for the first six hours after her operation, Baker, then an 81-year-old professor at the Johns Hopkins Bloomberg School of Public Health, was recovering well. That night, however, she hallucinated a fire raging through the hospital toward her room. Petrified, she repeatedly buzzed the nurses’ station, pleading for help. The next day she was back to her usual self. “It was the most terrifying experience I have ever had,” she says.
Baker’s waking nightmare was a symptom of postoperative delirium, a state of serious confusion and memory loss that sometimes follows anesthesia. In addition to hallucinations, delirious patients may forget why they are in the hospital, have trouble responding to questions and speak in nonsensical sentences. Such bewilderment—which is far more severe than the temporary mental fog one might expect after any major operation that requires general anesthesia—usually resolves after a day or two.
Although physicians have known about the possibility of such confusion since at least the 1980s, they had decided, based on the then available evidence, that the drugs used to anesthetize a patient in the first place were unlikely to be responsible. Instead, they concluded, the condition occurred more often because of the stress of surgery, which might in turn unmask an underlying brain defect or the early stages of dementia. Studies in the past four years have cast doubt on that assumption, however, and suggest that a high enough dose of anesthesia can in fact raise the risk of delirium after surgery. Recent studies also indicate that the condition may be more pernicious than previously realized: even if the confusion dissipates, attention and memory can languish for months and, in some cases, years.
Researchers identify decision-making center of brain
Although choosing to do something because the perceived benefit outweighs the financial cost is something people do daily, little is known about what happens in the brain when a person makes these kinds of decisions. Studying how these cost-benefit decisions are made when choosing to consume alcohol, University of Georgia associate professor of psychology James MacKillop identified distinct profiles of brain activity that are present when making these decisions.
"We were interested in understanding how the brain makes decisions about drinking alcohol. Particularly, we wanted to clarify how the brain weighs the pros and cons of drinking," said MacKillop, who directs the Experimental and Clinical Psychopharmacology Laboratory in the UGA Franklin College of Arts and Sciences.
The study combined functional magnetic resonance imaging and a bar laboratory alcohol procedure to see how the cost of alcohol affected people’s preferences. The study group included 24 men, age 21-31, who were heavy drinkers. Participants were given a $15 bar tab and then were asked to make decisions in the fMRI scanner about how many drinks they would choose at varying prices, from very low to very high. Their choices translated into real drinks, at most eight that they received in the bar immediately after the scan. Any money not spent on drinks was theirs to keep.
The study applied a neuroeconomic approach, which integrates concepts and methods from psychology, economics and cognitive neuroscience to understand how the brain makes decisions. In this study, participants’ cost-benefit decisions were categorized into those in which drinking was perceived to have all benefit and no cost, to have both benefits and costs, and to have all costs and no benefits. In doing so, MacKillop could dissect the neural mechanisms responsible for different types of cost-benefit decision-making.
"We tried to span several levels of analysis, to think about clinical questions, like why do people choose to drink or not drink alcohol, and then unpack those choices into the underlying units of the brain that are involved," he said.
When participants decided to drink in general, activation was seen in several areas of the cerebral cortex, such as the prefrontal and parietal cortices. However, when the decision to drink was affected by the cost of alcohol, activation involved frontostriatal regions, which are important for the interplay between deliberation and reward value, suggesting suppression resulting from greater cognitive load. This is the first study of its kind to examine cost-benefit decision-making for alcohol and was the first to apply a framework from economics, called demand curve analysis, to understanding cost-benefit decision making.
"The brain activity was most differentially active during the suppressed consumption choices, suggesting that participants were experiencing the most conflict," MacKillop said. "We had speculated during the design of the study that the choices not to drink at all might require the most cognitive effort, but that didn’t seem to be the case. Once people decided that the cost of drinking was too high, they didn’t appear to experience a great deal of conflict in terms of the associated brain activity."
These conflicted decisions appeared to be represented by activity in the anterior insula, which has been linked in previous addiction studies to the motivational circuitry of the brain. Not only encoding how much people crave or value drugs, this portion of the brain is believed to be responsible for processing interceptive experiences, a person’s visceral physiological responses.
"It was interesting that the insula was sensitive to escalating alcohol costs especially when the costs of drinking outweighed the benefits," MacKillop said. "That means this could be the region of the brain at the intersection of how our rational and irrational systems work with one another. In general, we saw the choices associated with differential brain activity were those choices in the middle, where people were making choices that reflect the ambivalence between cost and benefits. Where we saw that tension, we saw the most brain activity."
While MacKillop acknowledges the impact this research could have on neuromarketing-or understanding how the brain makes decisions about what to buy-he is more interested in how this research can help people with alcohol addictions.
"These findings reveal the distinct neural signatures associated with different kinds of consumption preferences. Now that we have established a way of studying these choices, we can apply this approach to better understanding substance use disorders and improving treatment," he said, adding that comparing fMRI scans from alcoholics with those of people with normal drinking habits could potentially tease out brain patterns that show what is different between healthy and unhealthy drinkers. "In the past, we have found that behavioral indices of alcohol value predict poor treatment prognosis, but this would permit us to understand the neural basis for negative outcomes."
The research was published in the journal Neuropsychopharmacology March 3. A podcast highlighting this work is available at http://www.nature.com/multimedia/podcast/npp/npp_030314_alcohol.mp3.
(Image caption: Illustration of the mirror neuron system in the human brain. Credit: Jan Brascamp)
Brain mapping confirms patients with schizophrenia have impaired ability to imitate
According to George Bernard Shaw, “Imitation is not just the sincerest form of flattery – it’s the sincerest form of learning.” According to psychologists, imitation is something that we all do whenever we learn a new skill, whether it is dancing or how to behave in specific social situations.
Now, the results of a brain-mapping experiment conducted by a team of neuroscientists at Vanderbilt University strengthen the theory that an impaired ability to imitate may underlie the profound and enduring difficulty with social interactions that characterize schizophrenia. In a paper published online on Mar. 14 by the American Journal of Psychiatry, the researchers report that when patients with schizophrenia were asked to imitate simple hand movements, their brains exhibited abnormal brain activity in areas associated with the ability to imitate.
“The fact that patients with schizophrenia show abnormal brain activity when they imitate simple hand gestures is important because action imitation is a primary building block of social abilities,” said first author Katharine Thakkar, who conducted much of the research while completing her doctoral program at Vanderbilt and is now a post-doctoral fellow at the University Medical Center in Utrecht. “The ability to imitate is present early in life and is crucial for learning how to navigate the social world. According to current theory, covert imitation is also the most fundamental way that we understand the intentions and feelings of other people.”
The brains of jazz musicians engrossed in spontaneous, improvisational musical conversation showed robust activation of brain areas traditionally associated with spoken language and syntax, which are used to interpret the structure of phrases and sentences. But this musical conversation shut down brain areas linked to semantics - those that process the meaning of spoken language, according to results of a study by Johns Hopkins researchers.
The study used functional magnetic resonance imaging (fMRI) to track the brain activity of jazz musicians in the act of “trading fours,” a process in which musicians participate in spontaneous back and forth instrumental exchanges, usually four bars in duration. The musicians introduce new melodies in response to each other’s musical ideas, elaborating and modifying them over the course of a performance.
The results of the study suggest that the brain regions that process syntax aren’t limited to spoken language, according to Charles Limb, M.D., an associate professor in the Department of Otolaryngology-Head and Neck Surgery at the Johns Hopkins University School of Medicine. Rather, he says, the brain uses the syntactic areas to process communication in general, whether through language or through music.
Limb, who is himself a musician and holds a faculty appointment at the Peabody Conservatory, says the work sheds important new light on the complex relationship between music and language.
"Until now, studies of how the brain processes auditory communication between two individuals have been done only in the context of spoken language," says Limb, the senior author of a report on the work that appears online Feb. 19 in the journal PLOS ONE. “But looking at jazz lets us investigate the neurological basis of interactive, musical communication as it occurs outside of spoken language.
"We’ve shown in this study that there is a fundamental difference between how meaning is processed by the brain for music and language. Specifically, it’s syntactic and not semantic processing that is key to this type of musical communication. Meanwhile, conventional notions of semantics may not apply to musical processing by the brain."
To study the response of the brain to improvisational musical conversation between musicians, the Johns Hopkins researchers recruited 11 men aged 25 to 56 who were highly proficient in jazz piano performance. During each 10-minute session of trading fours, one musician lay on his back inside the MRI machine with a plastic piano keyboard resting on his lap while his legs were elevated with a cushion. A pair of mirrors was placed so the musician could look directly up while in the MRI machine and see the placement of his fingers on the keyboard. The keyboard was specially constructed so it did not have metal parts that would be attracted to the large magnet in the fMRI.
The improvisation between the musicians activated areas of the brain linked to syntactic processing for language, called the inferior frontal gyrus and posterior superior temporal gyrus. In contrast, the musical exchange deactivated brain structures involved in semantic processing, called the angular gyrus and supramarginal gyrus.
"When two jazz musicians seem lost in thought while trading fours, they aren’t simply waiting for their turn to play," Limb says. "Instead, they are using the syntactic areas of their brain to process what they are hearing so they can respond by playing a new series of notes that hasn’t previously been composed or practiced."
Study uncovers surprising differences in brain activity of alcohol-dependent women
A new Indiana University study that examines the brain activity of alcohol-dependent women compared to women who were not addicted found stark and surprising differences, leading to intriguing questions about brain network functions of addicted women as they make risky decisions about when and what to drink.
The study used functional magnetic resonance imaging, or fMRI, to study differences between patterns of brain network activation in the two groups of women. The findings indicate that the anterior insular region of the brain may be implicated in the process, suggesting a possible new target of treatment for alcohol-dependent women.
"We see that the network dynamics of alcohol-dependent women may be really different from that of healthy controls in a drinking-related task," said Lindsay Arcurio, a graduate student in the Department of Psychological and Brain Sciences. "We have evidence to suggest alcohol-dependent women have trouble switching between networks of the brain."
The research is part of a larger new effort to understand the differences between men and women with respect to alcohol. Arcurio said most of the research on alcohol dependence has been conducted with men or groups of men and women. Yet several factors make looking at women “really important.”
One such factor is that the physiological effects of drinking alcohol, which include liver damage, heart disease or breast cancer, set in much earlier in women than in men. For this reason, the suggested limit on the number of drinks per week that women can safely consume is eight, whereas for men, it is 14. Secondly, binge-drinking in women is on the rise. One in five adolescent girls is binge-drinking three times a month. In women between the ages of 18 and 54, that number is one in eight.
A ‘sledgehammer’ approach to defining differences in brain network activation
Research on decision-making mechanisms in alcohol-dependent individuals typically involves a general risk-taking situation in which money or points are at stake. In this study, participants were placed in the fMRI brain scanner and asked to consider low-risk and high-risk situations specifically related to alcohol — what the researchers describe as “ecological” tasks. Participants were then asked to make decisions regarding control stimuli — food as well as a presumably neutral stimuli, a stapler — to observe whether risky behavior was greater with respect to drinking than with these other items. The same picture cues were used to present high-risk and low-risk scenarios, and these two extremes were as follows:
For the low-risk situation, participants were told: Imagine you are at a bar. You are offered a drink, already paid for, with two shots of alcohol, and you have a safe ride home. For the high-risk, they were told: You are at a bar and are offered a drink already paid for, with six shots of alcohol, but you do not have a safe ride home.
The reason for such an extreme contrast between the two situations, Arcurio said, is that “as one of the first ecological tasks used in the scanner, we wanted to take a sledgehammer approach to really find the differences between cases that are definitely high-risk and those that are definitely low-risk.”
The findings, however, reflect an equally sharp contrast in differences between the brain network activation in alcohol-dependent women versus the controls.
For the control group, high-risk decisions to drink led to the deactivation of regions associated with “approach behavior,” deciding to take the drink in a risky situation. Conversely, women in the control group activate regions associated with the default mode network, a region traditionally thought to involve resting-state behavior or inactive or relaxed mental state, but which some now speculate plays a role in conceptualizing one’s future.
"It gets really interesting," Arcurio said, "comparing this pattern of activation to those in alcohol-dependent women, who behaviorally say they’re more likely to take the high-risk drink compared to the controls. They don’t deactivate anything. In contrast to the controls, alcohol-dependent women activate all three regions in question. They activate regions associated with reward (which release dopamine). They also activate frontal control regions involved in cognitive control and regions associated with the default mode network, involved in resting-state behavior. They are activating everything."
The investigators infer from these findings that alcohol-dependent women have trouble switching between networks. Being unable to activate one region and deactivate another in response to an alcohol-related situation means they are unable to use one strategy over another.
Furthermore, Arcurio said, “a lot of evidence suggests that switching between networks is influenced by the anterior insular and anterior cingulate regions of the brain, and we did find major differences in the insula between the alcohol-dependent women and controls. We’re thinking the issue is pinpointed to that region.”
The researchers are now running analyses to test the hypothesis that the insula helps in this process, which could offer new possibilities for intervention, with both behavioral therapy and medication.
The research is part of a whole research program, both planned and in the works, to further explore the questions about risky decision-making in alcohol-dependent women: studies of adolescent drinking, risky sexual behavior in alcohol-dependent women, the interaction of visual networks with decision-making networks, as well as the way music (or auditory networks) interacts with decision-making mechanisms in alcohol-dependent women. In the latter experiment, college-age participants choose a song that they associate with drinking and one with quiet reflection.
"There’s a lot of Miley Cyrus in the first category," Arcurio said.
(Source: news.indiana.edu)
![Researchers find brain’s ‘sweet spot’ for love in neurological patient
A region deep inside the brain controls how quickly people make decisions about love, according to new research at the University of Chicago.
The finding, made in an examination of a 48-year-old man who suffered a stroke, provides the first causal clinical evidence that an area of the brain called the anterior insula “plays an instrumental role in love,” said UChicago neuroscientist Stephanie Cacioppo, lead author of the study.
In an earlier paper that analyzed research on the topic, Cacioppo and colleagues defined love as “an intentional state for intense [and long-term] longing for union with another” while lust, or sexual desire, is characterized by an intentional state for a short-term, pleasurable goal.
In this study, the patient made decisions normally about lust but showed slower reaction times when making decisions about love, in contrast to neurologically typical participants matched on age, gender and ethnicity. The findings are presented in a paper, “Selective Decision-Making Deficit in Love Following Damage to the Anterior Insula,” published in the journal Current Trends in Neurology.
“This distinction has been interpreted to mean that desire is a relatively concrete representation of sensory experiences, while love is a more abstract representation of those experiences,” said Cacioppo, a research associate and assistant professor in psychology. The new data suggest that the posterior insula, which affects sensation and motor control, is implicated in feelings of lust or desire, while the anterior insula has a role in the more abstract representations involved in love.
In the earlier paper, “The Common Neural Bases Between Sexual Desire and Love: A Multilevel Kernel Density fMRI Analysis,” Cacioppo and colleagues examined a number of studies of brain scans that looked at differences between love and lust.
The studies showed consistently that the anterior insula was associated with love, and the posterior insula was associated with lust. However, as in all fMRI studies, the findings were correlational.
“We reasoned that if the anterior insula was the origin of the love response, we would find evidence for that in brain scans of someone whose anterior insula was damaged,” she said.
In the study, researchers examined a 48-year-old heterosexual male in Argentina, who had suffered a stroke that damaged the function of his anterior insula. He was matched with a control group of seven Argentinian heterosexual men of the same age who had healthy anterior insula.
The patient and the control group were shown 40 photographs at random of attractive, young women dressed in appealing, short and long dresses and asked whether these women were objects of sexual desire or love. The patient with the damaged anterior insula showed a much slower response when asked if the women in the photos could be objects of love.
“The current work makes it possible to disentangle love from other biological drives,” the authors wrote. Such studies also could help researchers examine feelings of love by studying neurological activity rather than subjective questionnaires.](http://41.media.tumblr.com/2d1eddcf4879fd3a371f4da4e8485254/tumblr_n11o2503cE1rog5d1o1_500.jpg)
Researchers find brain’s ‘sweet spot’ for love in neurological patient
A region deep inside the brain controls how quickly people make decisions about love, according to new research at the University of Chicago.
The finding, made in an examination of a 48-year-old man who suffered a stroke, provides the first causal clinical evidence that an area of the brain called the anterior insula “plays an instrumental role in love,” said UChicago neuroscientist Stephanie Cacioppo, lead author of the study.
In an earlier paper that analyzed research on the topic, Cacioppo and colleagues defined love as “an intentional state for intense [and long-term] longing for union with another” while lust, or sexual desire, is characterized by an intentional state for a short-term, pleasurable goal.
In this study, the patient made decisions normally about lust but showed slower reaction times when making decisions about love, in contrast to neurologically typical participants matched on age, gender and ethnicity. The findings are presented in a paper, “Selective Decision-Making Deficit in Love Following Damage to the Anterior Insula,” published in the journal Current Trends in Neurology.
“This distinction has been interpreted to mean that desire is a relatively concrete representation of sensory experiences, while love is a more abstract representation of those experiences,” said Cacioppo, a research associate and assistant professor in psychology. The new data suggest that the posterior insula, which affects sensation and motor control, is implicated in feelings of lust or desire, while the anterior insula has a role in the more abstract representations involved in love.
In the earlier paper, “The Common Neural Bases Between Sexual Desire and Love: A Multilevel Kernel Density fMRI Analysis,” Cacioppo and colleagues examined a number of studies of brain scans that looked at differences between love and lust.
The studies showed consistently that the anterior insula was associated with love, and the posterior insula was associated with lust. However, as in all fMRI studies, the findings were correlational.
“We reasoned that if the anterior insula was the origin of the love response, we would find evidence for that in brain scans of someone whose anterior insula was damaged,” she said.
In the study, researchers examined a 48-year-old heterosexual male in Argentina, who had suffered a stroke that damaged the function of his anterior insula. He was matched with a control group of seven Argentinian heterosexual men of the same age who had healthy anterior insula.
The patient and the control group were shown 40 photographs at random of attractive, young women dressed in appealing, short and long dresses and asked whether these women were objects of sexual desire or love. The patient with the damaged anterior insula showed a much slower response when asked if the women in the photos could be objects of love.
“The current work makes it possible to disentangle love from other biological drives,” the authors wrote. Such studies also could help researchers examine feelings of love by studying neurological activity rather than subjective questionnaires.
Mathematical beauty activates same brain region as great art or music
People who appreciate the beauty of mathematics activate the same part of their brain when they look at aesthetically pleasing formula as others do when appreciating art or music, suggesting that there is a neurobiological basis to beauty.
There are many different sources of beauty - a beautiful face, a picturesque landscape, a great symphony are all examples of beauty derived from sensory experiences. But there are other, highly intellectual sources of beauty. Mathematicians often describe mathematical formulae in emotive terms and the experience of mathematical beauty has often been compared by them to the experience of beauty derived from the greatest art.
In a new paper published in the open-access journal Frontiers in Human Neuroscience, researchers used functional magnetic resonance imaging (fMRI) to image the brain activity of 15 mathematicians when they viewed mathematical formulae that they had previously rated as beautiful, neutral or ugly.
The results showed that the experience of mathematical beauty correlates with activity in the same part of the emotional brain – namely the medial orbito-frontal cortex – as the experience of beauty derived from art or music.
Professor Semir Zeki, lead author of the paper from the Wellcome Laboratory of Neurobiology at UCL, said: “To many of us mathematical formulae appear dry and inaccessible but to a mathematician an equation can embody the quintescence of beauty. The beauty of a formula may result from simplicity, symmetry, elegance or the expression of an immutable truth. For Plato, the abstract quality of mathematics expressed the ultimate pinnacle of beauty.”
“This makes it interesting to learn whether the experience of beauty derived from such as highly intellectual and abstract source as mathematics correlates with activity in the same part of the emotional brain as that derived from more sensory, perceptually based, sources.”
In the study, each subject was given 60 mathematical formulae to review at leisure and rate on a scale of -5 (ugly) to +5 (beautiful) according to how beautiful they experienced them to be. Two weeks later they were asked to re-rate them while in an fMRI scanner.
The formulae most consistently rated as beautiful (both before and during the scans) were Leonhard Euler’s identity, the Pythagorean identity and the Cauchy-Riemann equations. Leonhard Euler’s identity links five fundamental mathematical constants with three basic arithmetic operations each occurring once and the beauty of this equation has been likened to that of the soliloquy in Hamlet.
Mathematicians judged Srinivasa Ramanujan’s infinite series and Riemann’s functional equation as the ugliest.
Professor Zeki said: “We have found that activity in the brain is strongly related to how intense people declare their experience of beauty to – even in this example where the source of beauty is extremely abstract. This answers a critical question in the study of aesthetics, namely whether aesthetic experiences can be quantified.”
Professor Zeki added: “We have found that, as with the experience of visual or musical beauty, the activity in the brain is strongly related to how intense people declare their experience of beauty to be – even in this example where the source of beauty is extremely abstract. This answers a critical question in the study of aesthetics, one which has been debated since classical times, namely whether aesthetic experiences can be quantified.”