NRSC 4132 Blog

Recent consensus numbers indicate that roughly 20 million, or about 10%, of the current U.S. population reported practicing meditation in the last year! To many of us at CU, the practice of meditation is all too familiar - Boulder, CO is one of the most yoga- and meditation- active cities in the U.S.

A recent study in the Journal of Neuroscience by Zeidan et. al (http://www.jneurosci.org/content/31/14/5540.abstract) analyzes an interesting application of meditation: modulation of pain. In particular, the Shamantha model of meditation was examined, one which involves sustaining attention on the "changing sensations of breath, monitoring discursive events as they rise, disengaging from those events without affective reaction, and redirecting attention back to breath". In this study, the discursive event was pain, and subjects were assessed for their ability to dissociate cognition of the pain stimulus from pain response.

The study employs a novel form of fMRI called pulse arterial spine labeled (PASL) MRI, a form of imaging that quantifies cerebral blood flow (CBF). Blood oxygen-level dependent (BOLD) fMRI, the conventional form of fMRI, is useful for monitoring short spurts of activity, but it is susceptible to slow drifts in signal intensity over extended periods of time. Because the practice of meditation often requires ample time, PASL MRI is better suited than BOLD fMRI.

The experiment consisted of 15 healthy volunteers. Three groups were sampled: a control group that received no training, an experimental group that only received directions to focus attention to breathing (ATB), and an experimental group that was taught Shamantha meditation. Each group was brought into a neutral environment and was presented with a 6 min. noxious heat stimulus (at 49 deg Celsius), during which the control group was instructed to rest, the ATB group to focus on breathing, and the meditation group to meditate. Two MRI readings were taken on all groups during presentation of noxious stimuli: pre- and post-meditation training. Additionally, test subjects were asked to rate unpleasantness of pain through the Freiburg Mindfulness Inventory (FMI) shortform.

Interestingly, the results show that attention to breath alone has no effect on modulating pain response; ratings of pain intensity and unpleasantness were identical between the control and ATB groups prior to meditation training. After meditation training, the experimental groups exhibited a 57% decrease in pain unpleasantness ratings and a 40% decrease in pain intensity ratings relative to the control group. Statistical analysis shows that meditation-induced reductions in pain were associated with increased activity in the anterior cingulate cortex and anterior insula, areas involved in the cognitive recognition of pain. This may seem paradoxical at first, as a majority of past studies have reported increased activity of these areas increases pain experience.

It is important to note that Zeidan et. al clarify the increased activity of these areas with the concurrent reduction of activity in the orbitofrontal cortex (OFC), an area of the brain associated with emotional evaluation and response. Grant et. al (http://www.ncbi.nlm.nih.gov/pubmed/21055874) report a similar de-coupling of the dorsolateral prefrontal cortex (DLPFC) and the cingulate, suggesting that the DLPFC (like the OFC) functions to generate emotional response after the cingulate receives afferents from pain stimuli. Given this novel model of pain, it is not surprising that the anterior cingulate cortex and anterior insula were active in meditating individuals; the heightened activity of these areas allowed them to be aware of discursive events (pain stimuli), but the reduced activity of the OFC allowed them to dissociate their pain response and refocus their attention to breathing.

These results show that meditation may be a powerful, natural way of dealing with pain. In an era where opiates and pain relievers are often relentlessly abused, meditation may be the perfect solution. Maybe one day, we'll see NFL athletes meditate at the end of practices and games, or physical rehabilitation patients meditate daily to overcome the pain of a healing injury. Only time, and more research, can tell.

In the early ages, mankind was very segregated. There were nomads, warriors, hunters, etc. who occupied distinct geographical areas and practiced a very specific way of life. Over time, these cultures began to mesh, and today, nearly every nation is comprised of constituents hailing from all parts of the globe.

Interestingly, a recent study in Nature Neuroscience (http://www.nature.com/neuro/journal/v6/n12/abs/nn1156.html) indicates a neural mechanism for the integration of cultures. Specifically, Jennifer Richeson et. al conducted fMRI studies that identified regions of the brain allocated to repressing racial biases and prejudices.

Jennifer Richeson et. al designed their study to examine a previously proposed theory called "resource depletion". Prior research suggests that central executive processes are recruited "to combat the expression of stereotypes and negative attitudes that often come to mind automatically and unintentionally". The resource depletion theory postulates that the suppression of racial attitudes upon interracial contact temporarily depletes central executive control, and hence, performance on tasks requiring central executive control following interracial contact is diminished.

The study consisted of two experiments conducted on 15 Caucasian, American undergraduates. The first experiment involved individuals completing a survey on racial bias, then interacting with a black individual, and then completing an unrelated Stroop-color naming test that assesses executive control. In the second experiment, these individuals were presented with pictures of unfamiliar male black faces, and fMRI imaging was used to examine the activity of brain regions implicated in executive control during and immediately after the images were presented.

The fMRI imaging revealed heightened activity in the dorsolateral prefrontrol cortex (DLPFC) in individuals that exhibited racial biases. As expected, this increased activity in the DLPFC correlated to diminished performance on the Stroop-color naming test, indicating that executive control resources had been depleted following interracial contact. In contrast, there was no heightened activity in the DLPFC in controls (those who did not show racial biases on the initial survey), and these controls did not show diminished performance on the Stroop-color test.

The DLPFC is believed to directly influence the engagement of inhibition responses, such as suppression of racial biases. Another area of interest, the anterior cingulated cortex (ACC), is believed to sense situations/circumstances when such control is necessary. While fMRI imaging revealed increased activity of the DLPFC and ACC in racially biased individuals, only DLPFC activity correlated to diminished Stroop-color test performance. This indicates that while both areas may be important in regulating racial biases, the DLPFC region more directly affects performance on executive control tasks following interracial contact.

It is surprising that regions of the brain function to repress racial biases and stereotypes. More research is needed to identify what brain structures contribute to the development of these biases in the first place. Perhaps such research will lead to the development of drugs that promote cultural awareness and tolerance, something we could all use a dose of.

Focus on your breathing. As thoughts and emotions come to you, simply observe without judgment and dismiss them, as if they were just passing by outside your car window. Return to the sensations of air passing in through your nostrils, down your trachea and filling your lungs...

Sound like a yoga class? Hypnosis? Close, but even better. It's a trick you can keep up your sleeve to pull out the next time your body screams "Ouch!" And it works, according to a study published in the April, 2011 issue of the Journal of Neuroscience. (https://cuvpn.colorado.edu/content/31/14/,DanaInfo=www.jneurosci.org+5540.full.pdf+html)

Researchers took 15 young healthy volunteers, and applied a painful stimulus to their calves for about 6 minutes while instructing them to simply pay "attention to breath." Brain activity was recorded using fMRI before and during the noxious stimulus. Afterwards, the subjects also rated their subjective pain intensity and pain unpleasantness on a standard visual analog scale.

Subjects were then given instruction in Shamatha, a type of "mindfulness meditation" that involves focused attention on the sensations of the breath, while disengaging from intrusive thoughts or emotions. Subjects spent merely 20 minutes a day, for 4 days, learning the technique. The fMRI sequences were then repeated, with the subjects meditating as taught during the application of noxious stimulus.

Meditation has long been thought to modify our sensory experiences, but the specific brain mechanisms were mysterious. As expected by the researchers, the subjects' ratings of pain intensity and pain unpleasantness were lower during meditation than before the training. In fact, subjects rated their pain lower by 40% and 57% respectively!

New information also emerged. Several different brain mechanisms seemed to be working at once. fMRI showed that distinct brain regions were significantly more active during meditation, some of them associated with the cognitive modulation of pain; some related to emotion regulation; some tasked with reframing the contextual evaluation of sensory events; and others involved in interoceptive awareness (attention to sensations inside the body). Additionally, some areas such as the thalamus were deactivated during meditation, acting as a sort of gatekeeper for afferent nociceptive signals.

Thanks to these brain mechanisms, you can handle the pain - if you make friends with Shamatha. For a relatively small time investment (just 20 minutes a day for 4 days), you can acquire a skill that will last you a lifetime, and hone it with practice. By extension, the pain-reducing benefits of Shamatha could be used to brave a variety of "painful" circumstances, like speaking in front of a crowd or meeting your boyfriend's parents. Further, a host of other benefits of increased interoceptive awareness await, like "trusting your gut" or knowing when you need some exercise, or knowing when you've had enough pizza.

Try it; it can't hurt.

You just finished your 30 mile bike ride or just finished that triathlon you always wanted in great time.. Now your exhaustedâ?¦ now what why canâ??t you finish your thought? Is it possible that the muscle fatigued you experiences can impacted you mentally? Studies indicate that the mental and actual movements share overlapping neural substrates (Jeannerod, 2001; Fadiga and Craighero, 2004; Munzert et al., 2009) and preserve the same spatiotemporal characteristics according to Demougeot. Demougeot suggested that if the two components are related that one will have to mentally prepare or exercise the mind to have optimal performance. ..â??Appropriate mental training can enhance motor performance.â?? Demougeot seek to find the answer to have much physically activity or muscle fatigue will start to have an effect on the mental stabilization of oneâ??s cognitions? In their study they measured the temporal features of actual and mental movements before and after muscle fatigueâ?¦ â??A strong prediction is that duration of mental actions should be sensitive to muscle fatigue, because the forward model receives as input the efferent copy of inappropriate motor commands and the perturbed state of the arm, both caused by muscle fatigue.â??

To conduct their study they used seventeen adults who were all health with no neurological problems who they used as participates. The participates then were asked to move their arms, physically and then mentally at different angles in a conducted sequence. They then tested the participate before and after the muscle fatigue.

They discovered that muscle fatigue significantly influenced the mental aspect of the experiment. Demougeot discovered that muscle fatigue significantly influenced alterations in the signaling used in mental cognition. They also discovered actual movements were in general slower immediately after fatigue, but progressively returned to prefatigue values. When applied to their study they discovered that mental movements were faster immediately after fatigue and gradually returned to prefatigue values. Demougeot studied the motor effent outflow signals to justify their thesis and this is what the concluded â??However, its efferent copy is available to the forward model, which naturally predicts very fast movements. Since during mental movements there is not sensory information, and state estimation derives from forward model alone, the brain continues to simulate faster mental movements after fatigue based on inappropriate (large) neural drives. This explains why mental movements were consistently faster than actual movements after fatigue, at least until their complete adaptation. This process, i.e., state estimation without sensory feedback, also explains the slower update of motor controller (i.e., motor commands) during mental compared to actual movements after fatigue. â??

Though neuroimaging Demougeot discovered that muscle fatigue can greatly impact oneâ??s ability to mentally function as proven above. One can also conclude that next time you stay up to study all night for an exam (muscle fatigue) that it could be detrimental to our test grade. Demougeot proved that muscle fatigue influences motor performance and action planning. Itâ??s no longer enough for physically training but mentally training is required now too.

To read full article please follow https://cuvpn.colorado.edu/content/31/29/,DanaInfo=www.jneurosci.org+10712.full

Reconsolidation theory states that the reactivation of memories destabilizes them unless they are reconsolidated within a certain amount of time. A study by Susanne Diekelmann shows that memory reactivation actually serves different purposed when we are awake and when we are asleep. Apparently memory reactivation during slow wave sleep results in an immediate stabilization while reactivation during wakefulness still results in destabilization. Diekelmann and her lab reactivated memories by presenting subjects with odors, and used fMRI technology to image the brain during reactivation. Participants in this study learned during the evening in the presence of an experimental odor in order to establish a connection between the odor and the material being learned.

During slow wave sleep, the participants were presented with the odor and then awoken a few minutes later to be started learning an interference object location task. Reactivating memories using the presented odor during waking lead to a reduced ability to recall the original object location task when interference preceeded. Using the fMRI, they found that reactivation during slow wave sleep activated hippocampal and posterior cortical regions whereas reactivation during wakefulness activated activated prefrontal cortical areas. Their findings indicate that the reactivations of memory traces have opposite effects on memory during slow wave sleep and awake times.

This study makes me think about Jim Carey in Sunshine of the Spotless Mind, where he undergoes a procedure while sleeping to erase all of his memories of his ex-girlfriend. While this plot seems totally unrealistic, it may be something that will be plausible in the future. But according to this study, wouldn't it be more effective to try and erase memories while people are awake? Imagine. What would the world be like if we could selectively choose the things we want to remember and those we want to be erased from our lives? We build our personalities and choices off of previous experiences, and learn from our mistakes. If we erase our mistakes, aren't we just likely to make them again? I mean Jim Carey went looking for his ex-girlfriend again in the movie.

For more information or to read this study check out "Labile or Stable: Opposing Consequences for Memory While Reactivated during Waking and Sleep" in Nature Neuroscience.

Have you ever experienced a ?gut feeling?? Gut feelings are also known as intuitions. I?m sure you?ve all hear about your mother?s intuition? if not ? I?m sure she?ll tell you ?Mother knows best!? We all know things that weren?t taught to us?but we still know them. For example, best friend says she?s ?okay? but you know she isn?t or your newborn is sick. A gut feeling is a sudden, unexplained judgment where we don?t know the source of origin.

Science has started to research how the stomach and brain are interconnected. ?The concept that the gut and the brain are closely connected, and that this interaction plays an important part not only in gastrointestinal function but also in certain feeling states and in intuitive decision making, is deeply rooted in our language.?(Mayer, 2011)

In the August issue of Nature Review Neuroscience, the article ?Gut feelings: the emerging biology of gut?brain communication,? talks about the foundation of why there are such feelings and the pathways that are taken to create those feelings. ?Recent neurobiological insights into this gut?brain crosstalk have revealed a complex, bidirectional communication system that not only ensures the proper maintenance of gastrointestinal homeostasis and digestion but is likely to have multiple effects on affect, motivation and higher cognitive functions, including intuitive decision making.?(Mayer, 2011) The article discusses the enteric nervous system and the signaling pathways that the gut and brain used to communicate ??The brain communicates to the viscera, including the gastrointestinal tract, through multiple parallel pathways, including the two branches of the autonomic nervous system (ANS), the hypothalamic?pituitary?adrenal (HPA) axis and the sympatho?adrenal axis (modulating the gut-associated lymphoid tissue), and descending monoaminergic pathways (modulating gain of spinal reflexes and dorsal horn excitability). ? (Mayer, 2011) The article then discuss the effect of the stomach to the brain. Most of the consciously perceived information about the stomach is that it?s used for digestion?this isn?t new information. ?However, recent evidence suggests that various forms of subliminal interoceptive inputs from the gut, including those generated by intestinal microbes, may influence memory formation, emotional arousal and affective behaviours.? (Mayer, 2011)

So why do we make decision based off no information but off our ?gut feelings?? Mayer suggests that we have some ?neurological basis? when it comes to our gut-interactions. She suggests that our gut feeling based decision is due to an interoceptive map of gut responses that develops in infancy and continues to develop throughout our stages of life.

The future holds new research on the crosstalk between the stomach and the brain. The primary focus is the mapping associated with the two. ?This includes the remarkable success in mapping the functional neuroanatomy of the ENS, in our understanding of how the brain modulates these ENS circuits and gut functions, and in unraveling the complexity of gut to brain signaling through multiple parallel but interacting communication channels.? (Mayer, 2011) With our current advances in the study of gut feelings we still have many unanswered questions? stay tuned for what science discover next.
To read full article, please visit https://cuvpn.colorado.edu/nrn/journal/v12/n8/full/,DanaInfo=www.nature.com+nrn3071.html

The response of a brain while listening to music is very different than the response of the brain to many other types of stimuli. While observing a scene there is no direct way to see how the brain is processing the image. Many different part of the brain must integrate the cloudy points of stimulation (or lack of stimulations,) pattern recognition, and memory among other things for the person to perceive what it is they are looking at. It is a very subjective experience that is difficult for a neuroscientist to analyze. Sound on the other hand (especially simple rhythmic sound) is often very directly observable by many available neurological measurements including EEGs. This has recently been the center of much attention in neuroscience and had provided fodder for several books including This is Your Brain on Music by Daniel J. Levitin and Musicophelia by Oliver Sacks.
EEG studies of patient response to rhythmic beats is the focus of Tagging the Neuronal Entrainment to Beat and Meter from the Journal of Neuroscience published this July. This study tries to delineate how the human mind processes beats and meter in general. Previously many studies were done exploring how musical meter can create an expectation in the listener, you have probably experienced this yourself by tapping your foot to a song you?ve never heard before. Most music (maybe excluding some jazz and freeform types of music) follows some predictable pattern and our brains zero in on them (wonderful recognizers of pattern that they are.)The theory of resonance has been proposed to explain these observances hypothesizing that after certain exposure to the rhythmic beats (or music) large groups of neurons become ?entrained? and resonate at frequency correlating with the music?s beat. By altering the beats from what is expected scientists have studied what the call evoked potentials (or EPs.)
In the studies done in this particular article researchers at the Institute of Neuroscience of the Universite Catholique de Louvain in Brussels, Belgium had participants listen to a 2.4 Hz beat an imagine it as either a binary beat (1 2, 1 2, 1 2, as in a march) or ternary (1 2 3, 1 2 3, 1 2 3, like in a waltz.) As a control they had some participants listen to the beat but did not instruct them to image a particular meter. They then monitored the response of the participants? EEGs. The researchers found that EEGs showed increases in amplitude of subharmonic frequencies in the groups that were imagining the binary and ternary beats. That means in the control group they showed a strong 2.4 Hz signal the binary group showed strong 2.4 and 1.2 Hz signal and the ternary group showed strong 2.4, 1.6, and .8 Hz signals. This supports many of the previous research done on this topic showing that direct observation of the physical experience of music can be measured and quantified using existing mode of neurological research. This may open doors to understanding how the brain processes other types of stimuli and art in the future.

As people we all vary in personality, thought and emotion. We all know that. But, when it comes to the world we live in, does everyone see the same things? If I look at a beautifully orange colored flower, does the person sitting next to me see what I see? According to a study by Dr. Samuel Schwarzkopf the answer to this question may be no.

In Dr. Schwarzkopf's recent study, a negative correlation was found between the size of an individual?s central visual field, as defined as the surface area of a person's primary visual cortex (V1), and the magnitude of illusory perceptual effect of two different optical illusions. The first optical illusion is the Ebbinghaus illusion where two central circles are identical in size but appear to be different sizes to the viewer because of the surrounding circles. One circle is surrounded by 6 larger circles and the other surrounded by 8 smaller circles. The second illusion come from Ponzo and is an illusion in which two checkerboard circles are identical in design and size but appear different because of the three dimensional background.

The two illusions may have different mechanisms behind their perception. The article predicts that the Ebbinghaus illusion may be associated with the lateral connections in V1 and the Ponzo illusion mediated by "feedback projections from the areas that extract the three dimensional context of the background".

The subjective experience of how large the circles looked varied between subjects. As I previously stated, in a large sample population, Schwarzkopf found a significant negative correlation between the magnitude of both illusions and the surface area of V1. Using standard retinotopic mapping procedures with functional magnetic resonance imaging (fMRI), participants with a small functionally defined V1 surface area were found to have stronger perceptual illusion than subjects with a large V1. There was no significant correlation found between the V2 or V3 visual regions and magnitude of the size illusions.

The study mentions that future work will look into whether the individual differences found can be attributed only to V1 surface area size or whether other mechanisms such as the concentration of the inhibitory neurotransmitter GABA or possible differences in actual brain structure. Furthermore, individual differences in size perception exist but are there commonalities among similar populations? For example: do people with autism see sizes more similarly than when an autistic person is compared to a person with brain activity attributed with normality? What about the effect of color blindness on size perception?

Schwarzkopf's study helps remind us of the variations in brain structure that contribute to each of us being who we are. If we all see things differently, how does the way we see something affect how we feel about it?

The article detailing Schwarzkopf?s study can be found in Nature Neuroscience at http://www.nature.com/neuro/journal/v14/n1/full/nn.2706.html

Those of us in dating in high school in the late 80′s can attest to the stinging truth revealed in Def Leppard?s song, ?Love Bites? shortly after a nasty break-up. But it was only recently that scientists employing state-of-the-art brain imaging fMRI technology have been able to view the similarities between the biting pain of rejection from a lover and physical pain.

A study published in the April 12 issue of Proceedings of the National Academy of Science (PNAS) has provided the most direct evidence showing a common brain circuit underlying the pain of rejection and physical pain.

In their study, the researchers at Columbia University, University of Michigan and University of Colorado, Boulder studied 40 subjects who had experienced rejection and break-up with a lover within the past six months. They tested each subject on two tasks, a social rejection task and a physical pain task, while imaging their brains.

In the scanner, subjects looked at the faces of their ex and thought about how it felt during their split and a snapshot of their brain was taken. Next they were shown a headshot of a friend of the same sex as their former partner and thought about a recent positive experience they shared. This provided the social rejection condition.

To compare the social rejection experience to the experience of ?physical pain? they attached a thermal device to the volunteers? forearms and set it to produced a ?painful?, but not harmful level.

In both men and women, rejection and painful heat activated brain circuits underlying distress (e.g. Anterior Cingulate cortex) and the sensation of pain e.g. somatosensory cortex).

Although this seems seems intuitive from centuries of poetry, tragic plays and lyrics, knowledge at a mechanistic level showing the same circuits are activated gives scientists new ways to deal with both. It makes one wonder if taking pain-killers shortly after a break-up might be a treatment option.

The common mechanism between social rejection and physical pain may be one reason why heroin and alcohol, both analgesics for pain, are irresistible amongst country and grunge musicians whose melodic ruminations center on tragedy, angst and painful relationships. Kurt Cobain comes to mind when he said, ?Thank you for the tragedy. I need it for my art.?

Last year the British pop group ironically named, ?The Wanted?, brilliantly connected the idea that pain from being unwanted/rejected and searing physical pain were one and the same in their popular song ?Lose My Mind?. Here are the lyrics and the video

They say that time
Heals everything
But they don?t know you
And the scars you bring

?Cos you left a jagged hole
And I can?t stand it anymore

If heartache was a physical pain
I could face it I could face it
But you?re hurting me
From inside of my head
I can?t take it I can?t take it

I?m gonna lose my mind
I?m gonna lose my mind

I?d erase my thoughts
If only I knew how
Fill my head with white noise
If it would drown you out
Kill the sound

If heartache was a physical pain
I could face it I could face it

But you?re hurting me
From inside of my head
I can?t take it I can?t take it

I?m gonna lose my mind
I?m gonna lose my mind

And I?d rather be crazy
I?d rather go insane
Than having you stalk
My every thought
Then having you here inside my heart

If heartache was a physical pain
I could face it I could face it
But you?re hurting me
From inside of my head
I can?t take it I can?t take it

I?m gonna lose my mind
I?m gonna lose my mind