How Our Brain Lets Us Believe What We Want To Believe

MedicalResearch.com Interview with:

People demonstrate biased belief updating: They tend to regard good news indicating that personal risks are lower than expected, and to disregard bad news indicating that personal risks are higher than expected. Kuzmanovic and colleagues show that this optimism bias depends on the update valuation by the ventromedial prefrontal cortex (vmPFC) and its influence on the dorsomedial prefrontal cortex (dmPFC) associated with self-referential reasoning. Credit: Bojana Kuzmanovic

People demonstrate biased belief updating: They tend to regard good news indicating that personal risks are lower than expected, and to disregard bad news indicating that personal risks are higher than expected. Kuzmanovic and colleagues show that this optimism bias depends on the update valuation by the ventromedial prefrontal cortex (vmPFC) and its influence on the dorsomedial prefrontal cortex (dmPFC) associated with self-referential reasoning.
Credit: Bojana Kuzmanovic

Dr. Bojana Kuzmanovic PhD
Max Planck Institute for Metabolism Research
Translational Neurocircuitry Group
Cologne, Germany

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Do our beliefs depend on what we want to believe? Until now, researchers failed to show how interactions between brain regions mediate the influence of motivation to adopt desirable notions on ongoing reasoning. Our study used optimized design and analyses to rule out alternative explanations and to identify underlying neurocircuitry mechanisms.

MedicalResearch.com: What are the main findings?

Response: First, we demonstrated that people’s belief formation behavior depends on their preferences. When people were asked to reconsider their beliefs about their future outcomes, they tended to rely more strongly on good news and to disregard bad news.

Second, we showed that favorable belief updating activated the brain valuation system known to be responsive to rewards such as food or money (ventromedial prefrontal cortex, vmPFC). That is, the valuation system was activated when participants incorporated good news to improve their risk estimates, and when they disregarded bad news to avoid a worsening of their risk estimates.

And third, the valuation system influenced other brain regions that are involved in deriving conclusions about oneself (dorsomedial prefrontal cortex, dmPFC). Importantly, the more participants were biased in their belief formation behavior, the stronger was the engagement and the influence of the valuation system.

The influence of the valuation system on the reasoning system helps to understand how motivation can affect reasoning. It supports the idea that memories and knowledge we recall to form our beliefs are selected in such a way as to yield the desired conclusions. For example, when we wish to convince ourselves that our risk of having a heart attack is low although federal statistics indicate a higher risk, we might recall our healthy life style but not our family history of heart-related diseases, or neglect the fact that the federal population may have a comparable life style. Continue reading

Infants Are Lips Experts With Prominent Neural Map of Lips

MedicalResearch.com Interview with:

Andrew N. Meltzoff Ph.D. Job and Gertrud Tamaki Endowed Chair Co-Director, Institute for Learning & Brain Sciences (I-LABS) Professor of Psychology Elected member of the American Academy of Arts & Sciences. University of Washington, Box 357920 Seattle, WA 98195

Dr. Meltzoff

Andrew N. Meltzoff Ph.D.
Job and Gertrud Tamaki Endowed Chair
Co-Director, Institute for Learning & Brain Sciences (I-LABS)
Professor of Psychology
Elected member of the American Academy of Arts & Sciences.
University of Washington, Box 357920
Seattle, WA 98195

MedicalResearch.com: What is the background for this study? What are the main findings? 

Response: We are applying safe, noninvasive neuroscience techniques to examine the development of young children. We are especially interested in social-emotional learning and cognitive development. The way the body is represented in the brain is well-studied topic in cognitive neuroscience using adults, for example, the classical studies by W. Penfield on the ‘sensorimotor homunculus’ in the adult brain. The development of neural body map in human infants is, however, deeply understudied.

We think that the way the body is represented in the brain will provide important information about infant learning prior to language. For example, one of the chief avenues of learning in human infants is through observation and imitation. Infants watch what adults do and imitate those behaviors, rapidly learning about people, things, and causal relations. The mechanisms of imitation themselves are interesting. In order to imitate, infants need to know what part of their body to move and how to move it. We wanted to explore the representations of the human body in the infant brain prior to language. Continue reading

Understanding the Neuroscience of Creativity Through Music Improvisation

MedicalResearch.com Interview with:

Andrew Goldman PhD Laboratory for Intelligent Imaging and Neural Computing Department of Biomedical Engineering, Columbia University Presidential Scholar in Society and Neuroscience, Columbia University Andrew Goldman PhD
Laboratory for Intelligent Imaging and Neural Computing
Department of Biomedical Engineering, Columbia University
Presidential Scholar in Society and Neuroscience,
Columbia University 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: Many Western musicians have difficulty improvising, despite having extensive training and experience. These musicians learn about and use similar musical structures in their playing (like chords, scales, rhythmic patterns, etc.) as experienced improvisers, but they may know about them in different ways. In other words, different musicians have different ways of knowing and learning about similar musical structures. To understand which ways of knowing facilitate the ability to improvise contributes to an understanding of how people are able to use knowledge creatively. Western music provides an important opportunity to compare these different ways of knowing because in other improvisatory domains of behavior (like speaking), it is difficult to find people who know how to do it but cannot improvise with it (e.g., if you know a language, you can very likely improvise with that language).

In order to advance our understanding of these improvisatory ways of knowing, we compared musicians with varying degrees of improvisation experience in a task that tested how they categorized musical chords. In Western music, different chords are theorized to have similar “functions.” For example, on a guitar, there are different ways to play a C chord, and you could often substitute one for the other. You might even play another chord in place of the C chord and have it sound similar, or lead to a similar subsequent harmony. Improvisers often use notation that specifies classes of chords rather than specific realizations (versions) of a chord whereas those who do not typically improvise use notation that specifies the full realization of the chord. By analogy, one chef might use a recipe that calls for “citrus” (in music, a class of musical chord) while another chef’s recipe might specifically call for “lemon” (in music, a specific realization of a functional class of chords). We tested whether improvisers categorize similar-functioning harmonies as more similar to each other than different-functioning harmonies, and compared how less experienced improvisers categorize the same harmonies.

Our task required the musicians to listen to a series of repeating harmonies (the “standard” stimuli) and pick out occasional chords that were different in any way (the “deviant” stimuli). Some deviant stimuli were different versions of the standard chord (like limes in place of lemons) and some deviant stimuli were chords with different musical functions (like bananas instead of lemons).

The more experienced improvisers were better at detecting the function deviants than the exemplar deviants whereas the less experienced improvisers showed little difference in their ability to detect the two types of deviants. In other words, because improvisers categorize the different versions of the same chord as similar, they have a relatively harder time picking out the similarly functioning harmonies. This was measured using behavioral data, and electroencephalography (EEG), which can be used to provide a neural measure of how different stimuli are perceived to be from each other.

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Neurobiology Links Aggressive Behavior and Addiction

MedicalResearch.com Interview with:

Scott J. Russo PhD Fishberg Dept. of Neuroscience Friedman Brain Institute, and Center for Affective Neuroscience Icahn School of Medicine at Mount Sinai New York, NY

Dr. Russo

Scott J. Russo PhD
Fishberg Dept. of Neuroscience
Friedman Brain Institute, and Center for Affective Neuroscience
Icahn School of Medicine at Mount Sinai
New York, NY 

MedicalResearch.com: What is the background for this study? What are the main findings? 

Response: There is increasing evidence that aggressive behavior might share key features with addiction.  For example, aggressive mice develop positive associations with environmental cues associated with previous aggressive encounters (ie. they find aggression rewarding) and aggressive animals will work very hard to obtain access to a subordinate animal in order to attack them.

Some of the same brain regions that are activated in response to addictive drugs, like cocaine and morphine, are also activated by aggressive experience.  Thus we hypothesized that there may be shared neurobiological mechanisms between addiction and aggression.

Our study showed that there is accumulation of the addiction-related transcription factor, ΔFosB, in the nucleus accumbens, a brain region well know to regulate the rewarding and addictive properties of drugs of abuse.

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Do We Have Free Will? Neuroscientists Aren’t Sure

MedicalResearch.com Interview with:

Veljko Dubljević, Ph.D., D.Phil. Assistant Professor of Philosophy, Department of Philosophy and Religious Studies, and  Science Technology and Society Program, North Carolina State University Raleigh, NC 27607 

Dr. Veljko Dubljević

Veljko Dubljević, Ph.D., D.Phil.
Assistant Professor of Philosophy,
Department of Philosophy and Religious Studies, and
Science Technology and Society Program,
North Carolina State University
Raleigh, NC 27607 

MedicalResearch.com: What is the background for this study?

Response: There is considerable controversy about the interpretation of data of the neuroscientific studies done by Benjamin Libet. On the one hand, Libet claimed that his work disproves certain metaphysical conceptions of free will (Libertarianism), whereas it does not disprove others (e.g., Compatibilism). In a nutshell, the reason for these claims is that Libet found preparatory brain activity (Readiness Potentials or RPs) some 500ms before the conscious decision to act was felt by study participants. That seemed to exclude the possibility that mental causation was taking place. At the same time, the onset of movement left a time-window for a ‘veto-decision’. This led Libet to conclude that there is no ‘free will’, but that there is a ‘free won’t’.

On the other hand, there were many criticisms of the study – methodological or substantive. Most notably, Patrick Haggard argued that it is not RPs that are correlates of a decision to act, but Lateralized Readiness Potentials (LRPs). Haggard agreed with many critics of Libet in that RPs could be connected to a range of other phenomena, and that preparatory brain activity that is most important for a decision to act already has to be ‘lateralized’. Namely, the decision to move the left or right arm is critical in this regard, and will lead to RP being focused in one or the other hemisphere, thus making LRPs the point of interest for any conscious decision to act. All in all, Haggard claimed to have replicated Libet’s major findings, with the caveat that timing of LRPs excludes the time-frame for a ‘veto-decision’. This Haggard claimed makes the evidence more in line with the metaphysical doctrine of ‘hard determinism’, which excludes agency and responsibility.

Many other neuroscientists followed Libet’s (and Haggard’s) lead and these experiment became part of ‘lore’ in neuroscience education – many other labs performed similar experiments and claimed to basically replicate the findings.

Our study was the first to review all available evidence.

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Shifting Attention Causes Momentary Brain Freeze

MedicalResearch.com Interview with:

Alex Maier, PhD Assistant Professor of Psychology Assistant Professor of Ophthalmology and Visual Science Vanderbilt University

Dr. Maier

Alex Maier, PhD
Assistant Professor of Psychology
Assistant Professor of Ophthalmology and Visual Science
Vanderbilt University

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: We were interested in finding out about how the brain shifts attention from one location to another. We knew that when we attend a certain location, brain activity increases in a specific way. This increase in activity is how we perform better when we use attention. What we knew less about is what happens when attention moves between locations.

To our surprise, we found that there is a brief moment in between these attentional enhancements, while attention moves from one location to another, where the brain does the complete opposite and decreases its activity. Shifting attention thus has a brief negative effect on our brain’s ability to process information about the world around us.

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How Can Neuroscience Explain Our Attachment To Consumer Items?

MedicalResearch.com Interview with:

Tamara Masters, PhD Marketing Marriott School of Management Brigham Young University

Dr. Masters

Tamara Masters, PhD
Marketing
Marriott School of Management
Brigham Young University

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: As a marketing professor I have studied the disparity of what people are willing to sell items/products for and how much that differs from how much others are willing to pay.

I do research in consumer decision making and find the neurophysiological aspects of consumers fascinating.  I read medical and neuroscience research for fun and see many ways individuals may be effected in the use of their limited resources.  We are all consumers – many make purchases of some type daily – even it if it is to play online games or where and how to get our next meal.

The main findings relate to how a person is either attached to or feels an aversion to losing an object.  There has been debate as to which of these factors leads to a difference in buy and selling prices.  This research provides a new and unique look at how BOTH factors must be present for this disparity to emerge.  This research is unique because it uses combines the fields neuroscience, psychology and economics to explain something we all experience.

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Exploration During Adolescence Critical To Obtaining Wisdom Needed To Navigate Adulthood

MedicalResearch.com Interview with:

Dan Romer PhD Research director, Annenberg Public Policy Center Director of its Adolescent Communication Institute University of Pennsylvania

Dr. Dan Romer

Dan Romer PhD
Research director, Annenberg Public Policy Center
Director of its Adolescent Communication Institute
University of Pennsylvania

MedicalResearch.com: What is the background for this study?

Response: In recent years, findings from research in developmental neuroscience indicate that the myelination of the prefrontal cortex (PFC) extends into the third decade of life, proceeding more slowly than in other brain regions. Because subcortical and sensory brain regions appear to mature earlier, this and other findings have been taken as evidence that adolescents may have less ability to control their behavior than children do. These findings spawned theories of “imbalanced” adolescent brain development that were proposed to explain heightened vulnerability to risky behavior and adverse health outcomes during adolescence.

Although there is little doubt that as adolescents enter adulthood, they are at risk for many health outcomes that can accompany the initiation of such behaviors as driving, having sex, using drugs, and playing sports. But most adolescents make it through this period of development without serious health consequences. Thus, the argument that a brain deficit is responsible for such adverse health outcomes seemed to overgeneralize effects that only occur for a minority of adolescents. Furthermore, when my colleagues and I examined the evidence in support of imbalance theories, we found it unconvincing. Indeed, it seemed that findings from neuroscience were interpreted through the lens of stereotypes about adolescents that conflate exploration with impulsivity. That is, many of the risky behaviors that attract adolescents are novel activities that reflect lack of experience rather than lack of control over behavior.  Continue reading

Are Your Prefrontal Neurons Oscillating? You May Be In Love

MedicalResearch.com Interview with:

Dr. Robert Liu, PhD Silvio O. Conte Center for Oxytocin and Social Cognition Center for Translational Social Neuroscience Department of Biology Graduate Program in Neuroscience Emory University, Atlanta, Georgia

Dr. Liu

Dr. Robert Liu, PhD
Silvio O. Conte Center for Oxytocin and Social Cognition
Center for Translational Social Neuroscience
Department of Biology
Graduate Program in Neuroscience
Emory University, Atlanta, Georgia 

MedicalResearch.com: What is the background for this study? What are the main findings?

Response: This study describes for the first time some of the novel brain mechanisms underlying how social relationships are formed.  In this case we studied the formation of a pair bond in voles.  Pair bonding in voles is not exactly the same as love in humans, but we believe that pair bonding in voles likely shares many of the underlying neural mechanisms as falling in love in humans, such as developing a rewarding feeling towards your partner.

Basically, we discovered that rhythmic oscillations of groups of neurons in the prefrontal cortex, an area of the brain that is involved in decision making and executive function, can control the strength of oscillations at a different frequency in populations of neurons in the nucleus accumbens, an area that is involved in pleasure and reward, as well as addiction.  We show that the strength of that PFC-NAc control predicted how quickly animals would begin to show affectionate behavior, analogous to people who may fall in love quicker than others.  But the most intriguing thing was that when animals mated for the first time, the strength of the control of the reward system by the decision making circuit increased, and the greater the increase in that control, the faster the animal started huddling or showing affection toward its partner.  We think that this cortical control of the reward system allows for the neural encoding of the partner’s features (odors, sounds) to become stamped into the reward system, so that the partner becomes rewarding themselves.  Indeed in studies in humans, parts of the striatum, to which the nucleus accumbens belongs, become activated when men look at images of their lovers or when mothers look at images of babies.

We not only observed that during pair bond formation the cortex controls rhythmic activity within the reward system, but we actually recreated that communication using a highly innovative technique that allows us to control neural activity using light.  We expressed a light sensitive protein in the cortical neurons that project to the reward system, and then light stimulated those projections in the reward system in animals at the same frequency as normally happens during mating, but in this case the animals were not allowed to mate. By simply recreating the neural oscillatory control of the cortex of the reward area when the female was near the male, we biased how affectionately she acted towards him.

We think that the implications for this is not restricted to forming bonds or falling in love, but tells us something fundamental about how certain brain circuits communicate with each other to build social relationships, to make us feel pleasure from being with others that we like.  We believe that by understanding how social cues get instantiated into the brain’ reward system, we may ultimately be able to use this information to help people with impairments in the forming strong social relationships, such as in autism or schizophrenia.

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