Tag Archives: fMRI

Electric Feel

A section of the museum! Daft Punk, an electric music duo, is French.

While travelling in Paris, I’ve passed quite a few musicians performing on the streets, whether they are singing, playing an instrument, or both. As someone who listens to music almost nonstop, I always find myself feeling a little brighter after I pass by these performers during my daily outings. What can I say? Music makes me happy, and good music happier. It’s not often that one finds time and space just for listening to music, but the “Electro: From Kraftwerk to Daft Punk” exhibit at the Philharmonie de Paris offered me this very opportunity, revisualizing the sonic experience of electronic dance music (EDM) into an immersive physical space. Tracing the origins of EDM to the present and featuring the works by renowned duo Daft Punk, “Electro” left me thinking about EDM for quite some time after I’d left. How do our brains process and respond to music, and how might the case be different for EDM?

I went to Shaky Beats music festival a year ago. The festival had several EDM artists playing.

Research suggests that listening to music is more complex than we might think, as it activates an entire network of cortical and subcortical areas (Zatorre and Krumhansl, 2002). Even the perception of rhythm involves multiple brain regions (Zatorre et al., 2007). When we hear music we like, our reward systems may activate, and when we tap our feet or bob our heads, we do so almost unbeknownst ourselves through activation of the basal ganglia (Trost et al., 2014; Zatorre et al., 2007).

A recent functional magnetic resonance imaging (fMRI) study by Brodal and colleagues examined the relationship between rhythmic music and basal ganglia, an area of the brain typically associated with fine motor skills (Hikosaka et al., 2002; Brodal et al., 2017). To test participants, researchers created a continuous-stimulation design (10.16 minutes long, 120 beats per minute) using an EDM-style composition. Ambient noise generated by the MR scanner was synchronized with the music to mimic an accompanying instrument and to prevent disturbance of participants’ listening experiences. The continuous-stimulation design was a departure from previous studies’ use of short chunks of music, which Brodal and colleagues believed may have caused limitations (Brodal et al., 2017).

Regions researchers observed. (Brodal et al., 2017)

Researchers used stochastic dynamic causal modeling (sDCM), a technology used to examine interactions between auditory perception, rhythm processing, and reward processing, to observe connectivity in the auditory cortex, putamen/pallidum (PP), and ventral striatum/nucleus accumbens (VSNAc) of both hemispheres. The latter two grouped terms were chosen for this study because the low resolution of raw fMRI data prevented distinction between grouped locations.

The sDCM revealed significant connections between all three areas in both hemispheres, as well as reduced functional connectivity in the reward system. Results supported the hypothesis that stimulation from rhythmic EDM-like music decreases connectivity in the right VSNAc from and to the basal ganglia and auditory network. Stimulation also resulted in decreased self-inhibition via the VSNAc, as well as changed hemodynamic parameter of the VSNAc, suggesting an increased level of activation. Furthermore, reduced connectivity was observed in basal ganglia, reward system, basal ganglia and auditory network. Ultimately, results demonstrated reduced reward system connectivity in participants listening to rhythmic music, thus supporting the hypothesis that the ventral striatum/nucleus accumbens region plays a significant role in processing the emotions associated with listening to music (Koelsch, 2014).

As Brodal and colleagues note themselves, one weakness of the study is its methodological constraints. Though evidence already exists on rhythm and the observed effects, researchers’ use of only one music piece prevents confident establishment of a connection, at least in relation to the present study (Brodal et al., 2017). Furthermore, participants’ states while listening to the given music is only compared to one other state, the resting state. Brodal and colleagues note that it is thus impossible to definitively determine whether the observed effects emerged during the resting state (Brodal et al., 2017). Lastly, though not a weakness, laboratory conditions in the Brodal team’s study are far different from normal conditions in which one might listen to music. EDM in particular is often celebrated at large outdoor festivals, and it would be interesting to understand how music interacts with festival environments and other relevant factors to affect our emotions, reward circuits, and capacity for inhibition.

Or who knows? Maybe I’ll see for myself at my next EDM festival. In an era of increasing technologization, electronic music represents not only technology, but also the capability of technology to bring humans together. And it’s comforting knowing that something so powerful can serve us by bringing us joy.

 

References

Brodal HP, Osnes B, Specht K (2017) Listening to rhythmic music reduces connectivity within the basal ganglia and the reward system. Frontiers in Neuroscience. 11:153. https://doi.org/10.3389/fnins.2017.00153.

Hikosaka O, Nakamura K, Sakai K, Nakahara H (2002) Central mechanisms of motor skill learning. Current Opinion in Neurobiology 12(2):217-222. https://doi.org/10.1016/S0959-4388(02)00307-0.

Koelsch S (2014) Brain correlates of music-evoked emotions. Nature Reviews: Neuroscience. 15:170-180. https://doi.org/10.1016/j.plrev.2015.03.001.

Cité de la Musique: Philharmonie de Paris (n.d.) The Electro exhibition.

Trost W, Frühholz S, Schӧn D, Labbé C, Pichon S, Grandjean D, Vuilleumier P (2014) Getting the beat: Entrainment of brain activity by musical rhythm and pleasantness. NeuroImage 103:55-64. https://doi.org/10.1016/j.neuroimage.2014.09.009.

Zatorre RJ, Chen JL, Penhune VB (2007) When the brain plays music: Auditory-motor interactions in music perception and production. Nature Reviews: Neuroscience 8:547-558. https://doi.org/10.1038/nrn2152.

Zatorre RJ, Krumhansl CL (2002) Mental models and musical minds. Science 298:2138-2139. https://doi.org/10.1126/science.1080006.

Image 1-2 taken by myself

Image 3 taken from (Brodal et al., 2017).

OMG, More Stairs?!?

When I came to Paris, I thought I was prepared for everything: the bakeries, the museums, the landmarks, the culture — but nothing could have prepared me for the walking I was about to do. Unlike the suburban areas around Emory or my hometown of Topeka, Kansas, where a car is considered necessary for most outings, the streets of Paris are easily traversable by foot, and public transportation is much more accessible. And in a city so beautiful, I had a hard time refusing the ease of foot travel. Still, with the recent muggy weather, walking hasn’t felt quite as pleasant. People always say “no pain, no gain,” and I began to wonder what all my walking was doing for me brain-wise.

My steps before and after I came to Paris. As one can see, my steps significantly increased after I came to Paris, May 22th.

Turns out, there’s a lot to be gained from regular aerobic exercise. Consistent research has pointed to the role of physical activity in cognitive function and has grown in volume over the past decade (Soga et al., 2015). General movement has been suggested to contribute to brain plasticity, which in turn facilitates interaction between cognitive and motor functioning (Doyon and Benali, 2005). Furthermore, research has also linked physical activity to academic performance (Castelli et al., 2007). While these results doesn’t necessarily mean that taking up routine walking or running will guarantee better grades or memory, the two do seem to be invariably related.

Amidst this burgeoning research, Colcombe and colleagues decided to research the cortical mechanisms beneath cardiovascular fitness-related changes in cognitive function (Colcombe et al., 2004). Functional magnetic resonance imaging (fMRI) was used to study how changes in fitness might affect the brain. Researchers particularly focused on the anterior circular cingulate (ACC), an area of the limbic system linked to brain structures responsible for sensory, motor, emotional, and cognitive information (Bush et al., 2000).

The study took place in 2 segments, with Study 1 involving high-fit (HF) older adults, and Study 2 involving adults randomly assigned to either a cardiovascular fitness training (CFT) group or a stretching and toning group (control) (Colcombe et al., 2004). All participants in both groups underwent a flanker task in which they filtered and identified incongruent cues (Colcombe et al., 2004). The flanker test allowed researchers to study participants’ ability to filter and respond to relevant information (Colcombe et al., 2004). Researchers then compared cortical mechanisms triggered by incongruent clues to those triggered by congruent ones, to see whether HF adults would demonstrate higher activation in attention- and control-related regions (Colcombe et al., 2004).

fMRI scans of the ACC illustrate activation of different cortical areas in the task-related activity (Colcombe et al., 2004).

Sure enough, fMRI scans supported the study’s hypothesis that older adults with high levels of measured cardiovascular fitness would demonstrate significantly more activation in cortical regions linked with attention selection and control (Colcombe et al., 2004). These cortical regions include the medial frontal gyrus (MFG), superior frontal gyrus (SFG), and superior parietal lobe (SPL) (Colcombe et al., 2004). Significantly less activation was observed in the ACC, which is linked with behavioral conflict and adaptation of attentional control (Colcombe et al., 2004).

One weakness of the study by Colcombe and colleagues is the cross-sectional approach taken in Study 1. Being observational, cross-sectional studies are vulnerable to non-response bias, which can lead to a participant pool unrepresentative of the population (Sedgwick, 2014). Furthermore, data can only be collected during one set period of time, leaving researchers unable to create long-term representations of cause and effect (Sedgwick, 2014). However, it is important to note that longitudinal studies might also be difficult to complete with older participants, due to possible interference from disease or other age-related complications (Sedgwick, 2014). Ultimately, the research by Colcombe and colleagues was important at the time of its publication because it expanded upon existing research regarding the underlying cortical mechanisms of cardiovascular fitness.

More recent research by Brockett and colleagues suggests that physical exercise may contribute to extensive plasticity and increased cognitive functioning (Brockett et al., 2015). Rats who ran for moderate durations of 12 days were able to better discriminate than control rats in a task testing medial prefrontal cortex (mPFC) function, though little difference was seen between both groups in a task testing perirhinal cortex (PRC) function (Brockett et al., 2015). In a second experiment, runner rats took less trials and errors than control sedentary rats to reach criteria for simple discrimination, reversal, extradimensional shift (Brockett et al., 2015). Researchers also tested whether running influences astrocytes, non-neural brain cells that communicate with neurons and suggest links to synaptic plasticity, learning, and memory (Brockett et al., 2015). Co-labelling of astrocytes with visual markers revealed increase in astrocytes cell body area in the hippocampus, mPFC, and OFC (Brockett et al., 2015). These results aligned with data from the behavioral tests, suggesting that physical exercise can enhance cognitive performance in tasks that activate the hippocampus, mPFC, and OFC (Brockett et al., 2015). The lack of significant change to the PRC suggests that routine running lacks observable relation to the PRC. Ultimately, results suggest greater cognitive performance in tasks reliant on the prefrontal cortex, as well as enhanced synaptic, dendritic, and astrocytic measures in several regions. This evidence supports the hypothesis that physical exercise contributes positively to plasticity and cognitive functioning. Together, both papers by Colcombe, Brockett, and their colleagues have contributed to the growing understanding that exercise generally promotes greater cognitive functioning.

Brockett and colleagues’ research has made me wonder how much I would have to run to achieve the human equivalent of a rat’s 12-day regimen. As a student, it’s incredibly easy to get sucked into the grind and become deskbound. But the grind is exactly why brain power is important for the students, and optimizing my brain power in exchange for a few minutes and some physical effort has started to sound like a much better idea than the old me would have thought.

References

Brockett AT, LaMarca EA, Gould E (2015) Physical exercise enhances cognitive flexibility as well as astrocytic and synaptic markers in the medial prefrontal cortex. Public Library of Science ONE 10(5): e0124859. https://doi.org/10.1371/journal.pone.0124859.

Bush G, Luu P, Posner MI (2000) Cognitive and emotional influences in anterior cingulate cortex. Trends in Cognitive Sciences. 4(6):215-222. https://doi.org/10.1016/S1364 6613(00)01483-2.

Castelli DM, Hillman CH, Buck SM, Erwin HE (2007) Physical fitness and academic achievement in third- and fifth-grade students. Journal of Sport and Exercise Psychology 29(2):239-252. https://doi.org/10.1123/jsep.29.2.239.

Colcombe SJ, Kramer AF, Erickson KI, Scalf  P, McAuley E, Cohen NJ, Webb A, Jerome GJ, Marquez DX, Elavsky S (2004) Cardiovascular fitness, cortical plasticity, and aging. Proceedings of the National Academy of Sciences of the United States of America            101(9):3316-3321. https://doi.org/10.1073/pnas.0400266101.

Doyon J, Benali H (2005) Reorganization and plasticity in the adult brain during learning of motor skills. Current Opinion in Neurobiology 15(2):161-167. https://doi.org/10.1016/j.conb.2005.03.004.

Sedgwick P (2014) Cross sectional studies: Advantages and disadvantages. BMJ 348. https://doi.org/10.1136/bmj.g2276.

Soga K, Shishido T, Nagatomi R (2015) Executive function during and after acute moderate aerobic exercise in adolescents. Psychology of Sport and Exercise 16:7-17. https://doi.org/10.1016/j.psychsport.2014.08.010.

Image 1 taken by myself.

Image 2 from Colcombe et al., 2004.

The Art (and Science) of People Watching

After my weekend exploring the Musee du Louvre, going to the Women’s World Cup, and riding my umpteenth trip on the metro, I noticed that my go to activity while I explore is people watching. People watching, in its purest form, is the idea of observing other people in a public setting. We all do it, whether we are aware of it or not, and it has a variety of results from my own experience as a seasoned player.

Location of where the Louvre right next to the Seine River

People watching takes on a different form where you are; you can get away with more than a glance at a sporting event  like the Women’s World Cup than you can in a cramped metro where everyone is trying, and sometimes not trying at all, to look at everything but the five different people close enough to count eyelashes. Even in those situations, you cannot help but take a millisecond scan of your surroundings just in case in you miss out on something compelling.

This is a part of everyday life and a hobby that I do almost daily. We’re doing the opposite of what we usually do when we people watch; instead of blocking out majority of the stimuli we encounter on a daily basis we take the time to take in every detail as it crosses our path. I started to wonder how people watching is so enjoyable despite the cacophony of stimuli we take in when we do this activity.

Main entrance to the Louvre: Prime location for art appreciation and people watching!

It turns out that people watching requires activation in three different brain networks to during people watching (Quadflieg & Koldewyn, 2017). For example, the person perception network (PPN) is a brain network of brain structures that examine a person’s individual appearance and the way they move which is important to decipher an overall person to person encounter (Quadflieg & Koldewyn, 2017). One specific brain area in the PPN that supports the PPN’s overall function is the posterior superior temporal sulcus (pSTS), but it was not explicitly seen that the pSTS was active while observing social interactions until one 2018 study (Walbrin, Downing, & Koldewyn, 2018).

To test the pSTS activation, the researchers asked fifty-five participants to view human like figures in two 8-second scenarios for multiple trials: one scenario had two figures socially interacting and the second scenario had the two figures doing independent activities (Walbrin, Downing, & Koldewyn, 2018). The researchers used fMRIs to compare pSTS activity when the participants viewed social interactions verse when the participants viewed individual actions. After testing, the researchers found that the right pSTS had a significantly higher activation as the participants viewed the figures interacting with each other compared to when the participants viewed figures doing individual activities (Walbrin, Downing, & Koldewyn, 2018).

Graph showing a significant change in percentage signal activation of the pSTS once shown social interactions verse independent actions

It’s great that the researchers recorded pSTS activation from people seeing direct social interaction because it helps focus further directions into how social patterns change when people have conditions that affect the pSTS. The researchers even looked at other brain areas thought to assist in people watching but in a different capacity than just surface level observations of the interaction. The researchers added a control where they examined the temporoparietal junction (TPJ). The TPJ helps in assigning people’s intentions with one another from what we observe, but it does not work on a board scale in analyzing social interactions verse individual interactions like the researchers predicted the pSTS to do (Quadflieg & Koldewyn, 2017).

While this control helped the researchers determine if pSTS functions specifically while viewing social interactions, an experiment looking into nonhuman subjects’ that have areas similar to the pSTS inhibited or lesioned with provide more concrete evidence to the pSTS functioning examining social interactions or people watching.

Nevertheless, it is still interesting how we have multiple brain networks and brain structures involved to help us understand what we are looking at as we scan our surroundings and the people within it.

In my opinion, people watching is a great skill to have especially in places you’ve never been to before. By watching the people around interacting with each other and their surroundings, I’m able to pick up on what’s acceptable and what’s not. Especially in Paris, I’m trying to do everything I can to blend in and not expose myself as the Lost American, a title I still haven’t been able to shake off.

USA vs. Chile Women’s World Cup. The BEST place to people watch: screaming Chilean grandparents, babies decked out in USA memorabilia, cursing in three different languages, and an indescribable energy you have to love

Even so, everyone still has instances where social cues fall through the cracks. It is those times when you realize that you haven’t moved quickly enough when there is a bike riding on the sidewalk as you walked to the Musee du Louvre or you  you’re taking your sweet time trying to get a glimpse of Hope Solo while someone waits patiently to get their new profile picture during half-time, or the numerous other fish out of water experiences that I have encountered in France. Thankfully, I’ve stopped being embarrassed in these situations and tried to do better for the future by sticking my faithful ally in people watching.

Because we have various brain networks like the PPN with brain structures like the pSTS present to determine most beneficial actions to blend in any situation or find most entertaining of scenarios, it’s not hard see why we continue to people watching at the most inopportune times. We have the wiring to help us bounce back from the mistakes we make.

Without the spatial and social awareness that comes from people watching, I would not have the same peculiar but truly fascinating experiences I’ve had throughout Paris. So, I’m keeping my eyes peeled for the next exciting exploration or the next cue that comes my way.

References

Children’s Healthcare of Atlanta. (n.d.). fMRI. Retrieved from https://www.youtube.com/watch?v=3fNf8KX1AlQ

Quadflieg, S., & Koldewyn, K. (2017). The neuroscience of people watching: how the human brain makes sense of other people’s encounters. Annals of the New York Academy of Sciences,1396(1), 166–182. https://doi.org/10.1111/nyas.13331

Walbrin, J., Downing, P., & Koldewyn, K. (2018). Neural responses to visually observed social interactions. Neuropsychologia,112, 31–39. https://doi.org/10.1016/j.neuropsychologia.2018.02.023

Image #1: [Screenshot of the Musee du Louvre]. Retrieved from https://www.google.com/maps/place/Louvre+Museum/@48.8606111,2.3354607,17z/data=!3m1!4b1!4m5!3m4!1s0x47e671d877937b0f:0xb975fcfa192f84d4!8m2!3d48.8606111!4d2.337644

Image #3: [Screenshot of the Figure 2]. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5899757/

Image #2 and #4 were taken by me

Where is the Spicy Food in Paris?

On every street in Paris, there are three things you are certain to find: a boulangerie (or two or three), some sort of bistro/brasserie/café, and a Franprix (my personal favorite, a small-scale grocery store). Clearly, cuisine is central to Parisian life. And often, the options boil down to baguettes, wine, and cheese.

a typical boulangerie (“Savouries Counter – La Renaissance Patisserie” by avlxyz is licensed under CC BY-SA 2.0)

As a lover of spicy foods, I was at a bit of a loss. After about a week into my stay in Paris, I was ready to reintroduce some of the essential components of my normal diet—mainly, I’m referring to chili paste and other spices. Perusing the Franprix directly below my apartment, I was shocked to see that there was only one option for hot sauce. Not only this, but every café and restaurant I had been to showed no promise of the tongue-scorching, eye-watering foods I love. So I had some questions: why do I enjoy spicy foods so much? How are they registered in my brain? Is there a certain part of my brain—specifically for processing spicy taste sensations–that is more active for me than for a French person?

my chili paste from Franprix (Personal Image)

Before attempting to tackle any of these questions, let’s first explore how our brains perceive sensory information from the world around us.
The five basic senses–sight, sound, smell, taste, and touch–all have particular areas of the brain (in the bumpy outer layer called the cortex) devoted to receiving signals from our eyes, ears, nose, mouth, and skin, respectively. The area of the brain that registers taste is called the gustatory cortex.

Basic taste perception  (Image from Frontiers for Young Minds)

Nestled in taste buds scattered about the surface of the tongue, special receptor cells interpret chemical stimuli as sweet, salty, bitter, sour, and umami. From there, signals are sent to sensory neurons and into the brain through cranial nerves (Breslin and Spector, 2008). Spicy foods are detected a bit differently than other tastes, since these signals involve pain receptors (Immke and Gavva, 2006). But, recent neuroscience research has been determined that these signals still activate the gustatory cortex, so they count as a legitimate tastes (Rudenga et al., 2010)! Therefore, it seems that French cuisine is indeed missing an entire taste sensation, and it happens to be the one that is my favorite.

Taste bud (Image from LumenLearning.com)

Now that we’ve legitimized these piquant flavor sensations, let’s dive deeper into the neuroscience behind them.

While scientists still don’t understand exactly how taste perception works, it is clear that capsaicin (the chemical responsible for the spicy qualities of many of my favorite foods) actually results in unique brain responses. Unlike the other tastes, spicy sensations are often accompanied by the release of endorphins (explaining how they can be perceived as pleasurable) and activation of the autonomic nervous system. This unconscious system of bodily regulation is responsible for the perspiration, higher body temperature, and a faster heart rate associated with “hot” foods (McCorry, 2007).

In a 2015 study entitled “The Brain Mechanisms Underlying the Perception of the Pungent Taste of Capsaicin and the Subsequent Autonomic Responses,” Kawakami et al. (2015) investigated how these bodily responses happen after someone eats spicy food. The authors knew that the gustatory cortex (consisting of the middle and posterior short gyri, or M/PSG, of the insular cortex) must somehow be in communication with the brain area controlling autonomic system responses (the anterior gyrus of the insular cortex, or ASG). But, it wasn’t clear how this communication was happening.

In order to test this, the researchers administered three different taste solutions (spicy, salty, and neutral) to twenty human study participants. As the subjects tasted the solutions, the researchers took a look at their brain activity.
The method they used to analyze brain activity is called functional magnetic resonance imaging (fMRI). This produces high-resolution images of the brain while it is in action. Blood oxygenation level-dependent (BOLD) signals show where oxygenated blood is being used, indicating which regions are using up the most resources (Logothetis, 2003).

The ASG and M/PSG (Image from Frontiers in Human Neuroscience journal, Kawakami et al., 2015)

After performing this test, the researchers compared the brain images from the subjects. Their main findings were that there was coordination between the activity of the M/PSG and the ASG when people eat spicy foods. This could mean that these two brain areas are syncing up in order to produce symptoms like sweating and a quickened heartbeat after spicy food is consumed. Moreover, these results support the findings of another study done with mice, which concluded that cells in the ASG and M/PSG synchronize their activity patterns when capsaicin is tasted (Saito et al., 2012).
Kawakami et al. (2015) also found that the ASG was even more active than the M/PSG in response to capsaicin. Not only that, but both brain regions were significantly more active in response to capsaicin compared to the other solutions!

In sum, this study and previous work has helped to explain how the brain registers the taste of “hot” foods in the gustatory cortex and coordinates it with autonomic nervous system activation. However, the researchers only tested three taste sensations, and clearly, there is still much to be discovered about how the neuroscience behind gustation. Future work will likely take a closer look at the connection between the ASG and the M/PSG, possibly providing more insight into why some people (like me) find these mildly painful sensations more enjoyable than others.

   Baguettes are a staple in the                   Parisian diet (“Bag It” by Very Quiet is licensed under CC BY-SA 2.0)

In the meantime, perhaps knowing that eating spicy foods more fully engages the brain will inspire the French to literally “spice up” their diets and rethink that bland baguette, or at least offer more options in their grocery stores. That would make this hot sauce-lover very happy, and it would add a whole new dimension to French cuisine!

 

References:

Breslin, P.A., Spector, A.C. (2008). Mammalian taste perception. Current Biology. 18:R148-155. doi: 10.1016/j.cub.2007.12.017.

Immke, D.C., Gavva, N.R. (2006). The TRPV1 receptor and nociception. Seminars in Cell and Developmental Biology. 17:852-591. doi: 10.1016/j.semcdb.2006.09.004.

Kawakami, S., Sato, H., Sasaki, A.T., Tanabe, H.C., Yoshida, Y., Saito, M., Toyoda, H., Sadato, N., Kang, Y. (2015). The brain mechanisms underlying the perception of pungent taste of capsaicin and the subsequent autonomic response. Frontiers in Human Neuroscience. 9:720. doi: 10.3389/fnhum.2015.00720.

Logothetis, N.K. (2003). The underpinnings of the BOLD functional magnetic resonance imaging signal. Journal of Neuroscience. 23:3963-3971. doi: 10.1523/JNEUROSCI.23-10-03963.2003.

McCorry, L.K. (2007). Physiology of the Autonomic Nervous System. American Journal of Pharmaceutical Education. 71:78.

Rudenga K., Green B., Nachtigal D., Small D.M. (2010). Evidence for an integrated oral sensory module in the human anterior ventral insula. Chemical Senses. 35:693–703. doi: 10.1093/chemse/bjq068.

Saito, M., Toyoda, H., Kawakami, S., Sato, H., Bae, Y.C., Kang, Y. (2012) Capsaicin induces theta-band synchronization between gustatory and autonomic insular cortices. Journal of Neuroscience. 32:13470-13487. doi: 10.1523/JNEUROSCI.5906-11.2012.

Images (in order of appearance):

https://www.google.com/url?sa=i&source=images&cd=&ved=2ahUKEwik5pOayNDiAhUFfBoKHRppA28QjRx6BAgBEAU&url=https%3A%2F%2Fwww.pagesjaunes.fr%2Fpros%2F05362487&psig=AOvVaw2ocJ8aEu44zmFV0LxJzoWx&ust=1559762799131578

https://kids.frontiersin.org/article/10.3389/frym.2017.00033

https://www.google.com/url?sa=i&source=images&cd=&ved=2ahUKEwjZqu6RzdDiAhVZBGMBHaXYCI4QjRx6BAgBEAU&url=https%3A%2F%2Fcourses.lumenlearning.com%2Fwaymaker-psychology%2Fchapter%2Freading-taste-and-smell%2F&psig=AOvVaw1-_gpFcoSBHOxphR9YgJhr&ust=1559764284849243

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4717328/

 

Hyperlinked Videos/Sites:

https://youtu.be/TuVcnR5zAWo

https://www.youtube.com/watch?v=wGXoYippog8

https://neuroscientificallychallenged.com/blog/2013/05/what-is-insula

Louis XIV’s Crib Was Cool, But Those Flowers Though

Now coming up on two weeks into my stay in Paris, I’m amazed at how much art seeing (and walking!) opportunities there are across the city. I went to the Palace of Versailles  this past weekend and learned a little bit more about myself in the process. The overall aesthetics of some of the rooms, like the Hall of Mirrors, were breathtaking. Throughout my time in France, the distinct architecture of everything still astonishes me. The fact that people could see a vision that combined order and beauty is a testament of the human ability. However, even though the palace exemplified all of these things with the added adventure of getting around, I still found myself more at peace and grounded in the presence of flowers. In a larger than life palace with years of French history intertwined in it, it was nothing compared to the gardens, random buildings’ intricate flower arrangements across town, and especially the unique paintings of gorgeous flower bouquet and sceneries that truly made me stop and smell the roses.

A random but greatly appreciated restaurant I came across while walking the Shakespeare and Company bookstore in the 5th Arrondissement of Paris.

I couldn’t imagine why the Palace didn’t resonance with me as much as moving through a museum did; it was kind of a museum in some respects. My sister was shocked to learn I didn’t have plans to go to the Palace before this past weekend. It had been one of her favorite places in France, and she expected me to have the same experience. Surprisingly, I didn’t get that overwhelming feeling of wonder and disbelief at the magnitude  that she and some of the people at the palace had. So, I started to research why do people have different aspects artistic expression that resonances with them more than others and came across the world of neuroaesthetics.

A map of the extensive grounds in the Palace of Versailles.

Neuroaesthetics is this field in neuroscience where researchers are trying to figure out what neural connections activate and interact while someone is having an aesthetic experience that causes joy or disgust (Belfi et al., 2019). The greater question of this field is exactly the question I was trying to answer: what makes something more appealing to one person opposed to another? The field has a large reach with questions like why humans  chose the mates that we do, why we decide on one consumer product over the other, and perception’s effect on how we communicate (Chatterjee and Vartanian, 2014).

Neuroaesthetics continues to shine light on subjects such as what neural networks are involved when we view visual art. One study did this looking at how perception paintings as aesthetically pleasing or not affected what brain networks and structures were activate or deactivated (Belfi et al., 2019). Previous research found that the default mode network (DMN) was active when the person viewed artwork they thought was more moving, so the study recorded the DMN with fMRI processing as participants examined 90 paintings at various time lengths (Vessel et al., 2012) (Belfi et al., 2019). They found more DMN activation while the participants viewed a painting they thought was aesthetically pleasing compared to non-aesthetically pleasing works (Belfi et al., 2019). More DMN activation could lead brain system to associate a pleasing reward to the stimulus leading to a strong emotional response (Belfi et al., 2019).

So, while the Palace was objectively amazing to witness in real life, my perception of the art was not as high as the ones in the Musee D’Orsay leading me to some conclusions that my DMN could have been less active.

The Hall of Mirrors at the Palace of Versailles. My favorite part of the entire experience with the sunlight glittering on the chandeliers.

The museum experience is also a big determinate when viewing art as well. One study had a group of people examine art in a museum in Vienna and in a computer program to see if the way in which people received art would change their perception of it and their memory of the art (Brieber, Nadal, and Leder, 2015). Those that experienced the art through the museum had better recall of the art they saw and found the art to be more “arousing and pleasing” (Briber, Nadal, and Leder, 2015). So, there is the possibility that, in addition to a pretty weak DMN response, actually being in a museum where I expected to see this great art colored my perception of the paintings there compared to the palace’s paintings. The palace’s paintings I saw was great, but the palace did not support the type of art enjoying experience that a museum did. The participants in the study could stop and absorb a work as much as they wanted to much like my experience in the Musee D’Orsay: wandering around not knowing which work would capture me (Briber, Nadal, and Leder, 2015). This might have made the difference in my perception of the Palace as a whole.

It is pretty cool that even though we have the same brain systems activated with the aesthetically pleasuring figures, our internal states as well as the manner in which we consume art affects what we consider to be life changing pieces of art. I didn’t expect to stumble upon a whole section of neuroscience that I never encountered before to understand why Louis XVI’s chambers did not stimulate my DMN as much as Monet’s 1878 Chrysanthemums painting could.

Monet’s Chrysanthemums painting done in 1878. One of my many favorites by my favorite artist.

If you want to learn more about the neuroaesthetics, Anjan Chatterjee is a cognitive neuroscientist that specializes in neuroaesthetics with research on how “certain configurations of line, color, and form” affect what humans consider to be beautiful (“Anjan Chatterjee: How your brain decides what is beautiful | TED Talk,” n.d.) . He talks all about his study in this 2016 Ted Talk.

From what I’ve learned in my research, your surroundings have just as much to do how you perceive the beauty as your brain networks do. Appreciation of art is never linear, so even if something doesn’t elicit a strong DMN engagement, it’s can still be a great experience, nonetheless.

Next stop, fingers crossed, the Catacombs!

References

Anjan Chatterjee: How your brain decides what is beautiful | TED Talk. (n.d.). Retrieved June 4, 2019, from https://www.ted.com/talks/anjan_chatterjee_how_your_brain_decides_what_is_beautiful

Belfi, A. M., Vessel, E. A., Brielmann, A., Isik, A. I., Chatterjee, A., Leder, H., … Starr, G. G. (2019). Dynamics of aesthetic experience are reflected in the default-mode network. NeuroImage, 188, 584–597. https://doi.org/10.1016/j.neuroimage.2018.12.017

Brieber, D., Nadal, M., & Leder, H. (2015). In the white cube: Museum context enhances the valuation and memory of art. Acta Psychologica, 154, 36–42. https://doi.org/10.1016/j.actpsy.2014.11.004

Chatterjee, A., & Vartanian, O. (2014). Neuroaesthetics. Trends in Cognitive Sciences, 18(7), 370–375. https://doi.org/10.1016/j.tics.2014.03.003

Vessel, E. A., Starr, G. G., & Rubin, N. (2012). The brain on art: intense aesthetic experience activates the default mode network. Frontiers in Human Neuroscience, 6. https://doi.org/10.3389/fnhum.2012.00066

Image #2: [Screenshot of the grounds at the Palace of Versailles]. Retrieved from https://www.google.com/maps/place/Palace+of+Versailles/@48.8047375,2.1106368,15z/data=!4m5!3m4!1s0x0:0x538fcc15f59ce8f!8m2!3d48.8048649!4d2.1203554

Image #1, #3, and #4 were taken by me

Love In Paris!

If you know me, you’ll know that one of my favorite films is the French movie, “Amélie” (2001). Set in none other than the charming French village of Montmartre, “Amélie” tells a whimsical story of attraction and love. Once a hub for working-class citizens, Montmartre drew many artists with its liberal reputation. Renowned painters van Gogh, Renoir, and Toulouse-Lautrec were among the many to call the village home (Myers, 2007).

In the film, Amélie works for the Monsieur Collignon at the Café des 2 Moulins, a real location in Montmartre.

I was thrilled to visit the village with a group of my friends. After a few hours exploring, one particular sight remained with me. A gate heavy with love locks — a common sight in the so-called city of love and a symbol of couples’ eternal love. Between the love locks, the cobbled streets, and Le Mur des Je T’aime, my Montmartre, like Amélie’s, spoke of whimsy and love.

Spanning 40 square meters, Le Mur des Je T’aime was created in 2000 and features the phrase “I love you” in 250 different languages. The red fragments represent pieces of a broken heart, and the wall itself represents the capacity for healing through love.

Theories of love have evolved and developed constantly for centuries. Some of us believe in love at first sight. Others, like those who hang their locks upon gates, believe in eternal love. All of us have experienced love in some form or another, whether it be companionate, romantic, or maternal.

One study aiming to answer the question of whether romantic love lasts, observed through functional magnetic resonance imaging (fMRI) that the test subjects, 10 women and 7 men in reported long-term romantic relationships,  exhibited significant brain activity in dopamine-rich areas and areas associated with maternal love when shown images specific to their romantic partners (Acevedo et al., 2012). Responses to long-term partners’ images were measured alongside control images of close friends, familiar acquaintances, and low-familiar acquaintances. Researchers gave participants questionnaires measuring romantic love, obsession, IOS (closeness with one’s partner), friendship-based love, sexual frequency, and relationship length. In short, activation patterns in patients’ brain regions suggested that subjects experienced pleasure when presented with stimuli related to their long-term romantic partners. The ventral tegmental area (VTA), an area of the brain often generally associated with romantic love, showed activation in long-term relationships as well. Interestingly, among activated regions was the posterior hippocampus, an area that seems to activate in response to hunger or cravings (LaBar et al., 2001; Pelchat et al., 2004) — which makes me feel a tiny bit better about my love for ice cream.

While signifiers of romantic love activated dopamine-rich brain areas related to desire, those related to friendship largely activated opiate-rich ones related to pleasure. The study cites a key distinction previously established by researchers Berridge and Robinson, between  “wanting” and “liking,” that positions the two as mutually exclusive. While wanting someone is related to the reward that long-term romantic bonds connote, liking someone is more so an aspect of attachment and pair-bonds. Acevedo and her team wrote that, as a drive, romantic desire is unlike basic emotions in that it is comparatively goal-driven and “hard to control” (Acevedo et al., 2012). They observed that the brains of those in long-term romantic relationships also exhibited significant activity in the opiate- and serotonin-rich areas associated with friendly attachment — activity that is absent from early-stage romance.

Romantic partners attach their locks to this gate in Montmartre to eternalize their love. Love locks are a common sight across Paris.

An article published by Song et al. in 2015 focuses on a similar study that supports the role of romantic love in altering brain architecture, results which align with those of previous fMRI studies (Song et al., 2015). Song et al. acknowledges the work of Acevedo et al. in using fMRI to propose brain regions related and unrelated to romantic love, as well as the work of later researchers (Cacioppo et al., 2012) in dividing these identified regions into those responsible for emotion, reward, and memory, and those responsible for social cues and memory. One weakness of the present study is its longitudinal approach, a model which often resists laboratory control. Song et al. suggest that future research conducted on the topic implement cognitive and behavioral tasks to directly test the hypothesis that love-related alterations of resting brain function reflect an evolutionary drive to select the most fit partner (de Boer et al., 2012). Still, despite its limitations, the study by Song et al. is ultimately valuable because it highlights the function of romantic love.

Ultimately, the study by Acevedo et al. posits that long-term relationships can sustain reward- and value-based brain signals similar to those typically observed during the beginning stages of love, while also fostering the type of “liking” associated with friendly attachment and bonding. In other words, long-term romantic love is possible, and one can love their partner and be their best friend, too.

Of the hundreds and thousands of Parisians and tourists who’ve eternalized their romances on locks upon the fences of Paris, maybe some will succeed. All of us will find love in Paris, whether it be with the city, other people, or life itself. And I can’t wait to find out what comes my way!

 

References

Acevedo BP, Aron A, Fisher HE, Brown LL (2012) Neural correlates of long-term intense romantic love. Social Cognitive and Affective Neuroscience 7:145-159. https://doi.org/10.1093/scan/nsq092.

Cacioppo S, Bianchi-Demicheli F, Frum C, Pfaus JG, Lewis JW (2012) The common neural bases between sexual desire and love: a multilevel kernel density fMRI analysis. The Journal of Sexual Medicine 9:1048-1054. https://doi.org/10.1111/j.1743-6109.2012.02651.x.

de Boer A, Van Buel EM, Ter Horst GJ (2012) Love is more than just a kiss: a neurobiological perspective on love and affection. Neuroscience 201:114-124. https://doi.org/10.1016/j.neuroscience.2011.11.017.

LaBar KS, Gitelman DR, Mesulam MM, Parrish TB (2001). Impact of signal-to-noise on functional MRI of the human amygdala. Neuroreport 12:3461–4.

Myers N (2007) The Lure of Montmartre, 1880–1900. Heilbrunn Timeline of Art History.

Paris Convention and Visitors Bureau (n.d.) Le mur des je t’aime. Paris.

Pelchat ML, Johnson A, Chan R, Valdez J, Ragland JD (2004) Images of desire: food-craving activation during fMRI. Neuroimage 23:1486–93.

Song H, Zou Z, Kou J, Liu Y, Yang L, Zilverstand A, Uquillas Fd,  Zhang X (2015) Love-related changes in the brain: a resting state functional magnetic resonance imaging study. Frontiers in Human Neuroscience. https://doi.org/10.3389/fnhum.2015.00071.

Image 1, Café des 2 Moulins from “Amélie” (2001): Wikimedia Commons.

Images 2-3 were taken by myself.

It’s Not Just a Phase, Mom- How Sad Music is More Enjoyable than Happy Music

In light of the recent music festival and the fact that music can be heard regularly throughout the Métro and streets of Paris, I decided to look into the effects of music on the brain. In my experience I’ve always found that, in a public setting such as the Métro, I prefer to hear people playing calming instrumental music, like an acoustic guitar, rather than an entire band playing an upbeat song. While this may just be based on personal opinion, I wanted to know if there was a neurobiological process that governed this reaction. Obviously, examining every sentiment or bias towards music is beyond the scope of one or two studies, so I refined my question: what brain processes drive us to form opinions of music that is perceptually happy or sad?

Figure 1: Map of all the Fête de la Musique major events in Paris- there’s music for all tastes!

My first inquiry led me to an article by Brattico et al. (2011) that aimed to show the difference in activity of certain brain regions from music that is happy or sad, and with or without lyrics. They hypothesized that songs with lyrics will activate the left fronto-temporal language network, while songs without lyrics would activate right-hemispheric brain structures. Also, they expected to observe activation of left-hemispheric auditory areas by happy music (which is richer in fast transitions) and of right-hemispheric areas by sad music (with slower “attacks” and tempos). They used fifteen subjects who were told to bring in 16 familiar music pieces: four sad and four happy pieces from favorite music, and four sad and four happy pieces from disliked or even hated music. The music, within the four categories, was then computer-analyzed to average the attack slope (sharpness of musical events, for example, most percussion would result in a high attack slope) and spectral centroid (brightness and frequency balance of the music, similar to timbre), as well as tempo and mode (major or minor chord quality) (Figure 2).

Figure 2: Differences of attacks slope, spectral centroid, tempo, and mode in the four music categories.

The subjects listened to 18 second excerpts of the music they brought while their brain activity was monitored. After the excerpts, they were asked if they liked or disliked the music, as well as if they thought the music was happy or sad. Their findings of the difference in activated areas between categories are shown in Figure 3. Although the researchers described in detail what each activated brain region meant in correlation with its usual information processing, I’ll only mention a few interesting points that relate to my original question:

  • Sad music induced activity in the right caudate head and the left thalamus. Interestingly, the left thalamus is one of only a few brain structures that is involved in processing sadness in faces, suggesting a link between emotions evoked by visual or auditory stimuli.
  • Also, sad music led to activity in both the subcortical stratial region, which is involved in judging musical and physical beauty.
  • Happy music without lyrics more strongly activated structures associated with perception and recognition of basic emotions, like the left anterior cingulate cortex and the right insula, than happy music with lyrics.
  • However, sad music led to wider brain activity during music with lyrics than without, such as emotion-related areas like the right claustrum and left medial frontal gyrus.

Figure 3: Differences in activation of brain regions due to music emotion and presence of lyrics. For example, “Lyrics > Instrumental” signifies the regions that were activated in lyrical music, but not in intrumental. ITG stands for inferior temporal gyrus, ACC stands for anterior cingulate cortex, Cau for caudate, Cun for cuneus, CG for cingulate gyrus, Dec for cerebellar declive, ITG stands for inferior temporal gyrus, Put for putamen, STG for superior temporal gyrus, TTG for transverse temporal gyrus, and Thal for thalamus.

Based off these results, the researchers concluded that instrumental music is efficient in conveying positive emotions, while sad emotions are reinforced when lyrics are present. They suggest that vocal cues in sad music activate deep emotion-related structures which produce mental associations with negative emotional experiences, as shown in activation of limbic and paralimbic regions. This activation causes people to have “moving” experiences.

Below are two pieces of music I think Brattico et al. would suggest have high emotional impact- a familiar sad song with vocals and a familiar instrumental happy song. How do they make you feel? (Songs are Hallelujah by Jeff Buckley and Canon in D by Pachelbel, I own no rights to these)

Overall, I thought the study provides a thorough analysis of the brain regions that are differentially activated during happy or sad music, and even considers the effect of lyrics. The only aspect of the experimental procedure that confused me was their decision to have the subjects bring in their own music. Although the researchers say that the subjects had similar familiarity with the music, there was probably some differing in familiarity throughout the categories. I, for one, would probably have a more difficult time finding four sad songs that I hate but know well, than I would in finding four happy songs that I like.

Something that I still didn’t understand fully was their mention of the underlying feelings of being “moved” from music. So, I looked at another article, this time by Vuoskoski and Eerola (2017), that examined the effect of perceptions of music, such as beauty, on this sentiment. They hypothesized that sadness in music has a positive association with beauty, and mediates the feeling of being moved, which in turn causes a sense of enjoyment or pleasure.

The experimental procedure consisted of having 19 music students listen to 27 short film excerpts. The participants then rated the perceived emotion of the music based on six scales: sad/melancholic, moving/touching, tender/warm, peaceful/relaxing, scary/distressing, and happy/joyful, as well as if they liked it or not. The correlation between the qualities is shown in Figure 4. As the table shows, beauty was shown to have a positive correlation with sadness and a high correlation with liking. Also, the perception of being moved was the most highly correlated with beauty and sadness. Overall, Vuoskoski and Eerola found that the indirect effect via movingness on liking was twice the magnitude of that via beauty, which suggests that perceived movingness acts as the largest link between sadness and liking. In other words, the sadder a song is, the more you will be “moved”, and the more you will enjoy it. It is important to point out that this is not saying that happy songs are unlikeable- there was still a positive correlation between happiness and liking, but it was slightly lower than that of sadness.

Figure 4: Correlation values between different emotional qualities of music and liking.

This study gives convincing, albeit initially difficult to understand, connections between sadness and enjoyment of music through the sentiment of “being moved”. The only downside of the study is that the participants were asked about how they thought the music sounded, not how it made them feel. Although it might only be a slight difference in wording, it could play a larger role in terms in relating the feelings to regional activation in the brain, like in the study by Brattico et al. However, by accepting that perception and feeling are inherently linked, we can conclude that the largest enjoyment can be obtained from sad music with vocals, as it strongly activates the regions of the brain that cause the listeners to be emotionally moved. I think an interesting future direction would be to see the effect of human interaction on enjoyment from sad music- I would assume that there would be less enjoyment out of listening to sad music in a group setting, as cultural norms would start to play a larger role.

Even though the findings indicate that sadness gives a higher level of enjoyment, I find it hard to believe that this would not differ between people. What do you think? Do you find that you have a more emotional or pleasurable experience when listening to sad music than happy music?

References:

Brattico E, Alluri V, Bogert B, Jacobsen T, Vartiainen N, Nieminen S, Mari Tervaniemi M (2011) A Functional MRI Study of Happy and Sad Emotions in Music with and without Lyrics. Frontiers in Psychology. 2:308.

Vuoskoski JK, Eerola T (2017) The Pleasure Evoked by Sad Music Is Mediated by Feelings of Being Moved. Frontiers in Psychology. 8:439.

Figure 1 was found through Creative Commons

Figure 2 and 3 were taken from the article by Brattico et al.

Figure 4 was taken from the article by Vuoskoski  and Eerola

Videos were taken from YouTube

La Rage dans les Rues

Whether it’s Friday evening during rush hour or Sunday morning or Tuesday at 2am, I always get to enjoy the lovely sounds of vehicles in Paris. Vehicles communicate in the most loud and obnoxious way, and I’m convinced that it’s even worse than fifteen American college students causing a raucous in the metro. See, these vehicles communicate sans blinkers or small toots. Instead, they scream at each other with blaring horns that could last up to five full seconds. And here I am on the edge of Paris city limits, my window overlooking a busy street and the perimeter highway.

View of the perimeter highway from my window

I know the traffic in Atlanta is bad, but at least cars don’t have conversations via honking there. I’m beginning to think that honking is a subset of the French language. It most likely has developed due to the insane intersections like the roundabout at the Arc de Triomphe.

Check out this video to see the roundabout in action: https://youtu.be/-2RCPpdmSVg

Traffic around the Arc de Triomphe

So what is behind this road rage of sorts? Impatience. The unwillingness to wait for someone or something and tending to be quickly irritated. While I don’t have any tendencies towards road rage, this is a concept I very much relate to. Pretty much everywhere I go, people walk incredibly slowly and often block the path I’m trying to walk on, and I don’t particularly enjoy it. I think we all get frustrated at some point during each day, but what causes some people to act out this frustration while others let it go? Do some people have more angry personalities than others? Studies have shown that even mentally healthy individuals can engage in consequential acts of aggression (Anderson & Bushman, 2002), and some people have higher tendencies toward acts of aggression than others (Bettencourt et al., 2006). There are two types of aggressive personalities: general and displaced. When people with high displaced aggression are provoked, they harm innocent others and report increased levels of romantic partner abuse and driving aggression, whereas people with high general aggression do not (Denson et al., 2006).

Much of research concerning driving risk has found that emotional stability, agreeableness, and conscientiousness are factors in aggressive driving, which leads to risky driving outcomes (Chraif et al., 2016), but few studies have related behavioral observations and subjective ratings to particular areas of the brain. An fMRI study by Denson et al. (2009) sought out to better understand the neural processes underlying risk for aggression. Participants were provoked during a simple task through interruptions, and during one, the experimenter condescendingly implied that the participant was not intelligent enough to follow basic directions.

Figure 1 from Denson et al. (2009)

Interestingly, results from the fMRI imply that there is a neural basis for differences in aggressive behavior. Just seconds after being insulted, there were differences between activated regions of the brain, the dorsal anterior cingulate cortex (dACC) and the medial prefrontal cortex (mPFC), that correlated with different aggressive personalities. Individual differences in general aggression and the subjective experience of anger were more strongly correlated with activity of a region associated with the intensity of anger (dACC), whereas individual differences in displaced aggression were more strongly correlated with activity in a region associated with self-reflection and emotional regulation (mPFC) (Figure 1). Essentially, these data suggest that activity in these brain regions contributes to the differences in personality and behavior in response to provocation.

While Denson et al.’s results were convincing, especially through the use of a real-world provocation, I would love to see researchers take this study one step further to observe behavioral variances between those with different aggressive personalities. Though a bit of a stretch, with more research, one might find activation of the mPFC higher in those with road rage. Current models indicate that road rage is an incredibly complex phenomenon, with many contributing psychological factors (Lajunen & Parker, 2001). Perhaps cultural differences play a role, as well, in determining which type of aggressive personality an individual develops. If so, I would guess that the French are prone to high displaced aggression!

 

References:

Anderson, C. A., & Bushman, B. J. (2002). Human aggression. Annual review of psychology, 53(1), 27-51.

Bettencourt, B., Talley, A., Benjamin, A. J., & Valentine, J. (2006). Personality and aggressive behavior under provoking and neutral conditions: a meta-analytic review. Psychological bulletin, 132(5), 751.

Chraif, M., Aniţei, M., Burtăverde, V., & Mihăilă, T. (2016). The link between personality, aggressive driving, and risky driving outcomes–testing a theoretical model. Journal of Risk Research, 19(6), 780-797.

Denson, T. F., Pedersen, W. C., & Miller, N. (2006). The displaced aggression questionnaire. Journal of personality and social psychology, 90(6), 1032.

Denson, T. F., Pedersen, W. C., Ronquillo, J., & Nandy, A. S. (2009). The angry brain: Neural correlates of anger, angry rumination, and aggressive personality. Journal of Cognitive Neuroscience, 21(4), 734-744.

Lajunen, T., & Parker, D. (2001). Are aggressive people aggressive drivers? A study of the relationship between self-reported general aggressiveness, driver anger and aggressive driving. Accident Analysis & Prevention, 33(2), 243-255.

Traffic around the Arc de Triomphe: https://www.youtube.com/watch?v=-2RCPpdmSVg

Why put so much effort into learning a second language?

I have loved the study of French language since the day I started classes in 9th grade. Even though Neuroscience is my primary major, my French second major has always been a passion and an outlet from core sciences. While this is my 3rd time in Paris, I’ve (finally) noticed that fluency is coming more naturally, even when I’m flipping between conversations and homework in French to texts and Skype sessions in English. As a double major in French and Neuroscience, (naturally) I was interested in finding out how language development and the brain’s response are interconnected.

I have stayed with 3 homestays and lived in the Cité Universitaire over the past 5 years. [image souce: Google maps]

Over the past 5 years, I have stayed with 3 homestays and lived in the Cité Universitaire. [image souce: Google maps]

Paris is an ideal place to begin an inquiry into language and speech. The earliest roots can be attributed to the work pioneered here by Paul Broca, the French physician and anatomist, who studied the speech production centers of the brain – now termed Broca’s area.

The brain Broca studied at Musée Dupuytren [image source: google images]

I visited the brain Broca studied at Musée Dupuytren [image source: Google images]

Advances in technology not available to Broca in the 1800s allow us to use neuroimaging methods to reveal specific functional brain patterns in learning a second language. After doing some research on the effect of bilingualism on the brain, I think that what I’ve been experiencing in my studies abroad is likely an actual change in brain structure. A property known as plasticity is the ability of the brain to physically and functionally change in response to factors such as environmental stimuli or cognitive demand (Stein et al., 2010). This process occurs in everyone who learns or speaks a second language, which turns out to be over half the global population (Bialystok and Barac, 2013). Learning a language in addition to your native tongue induces these changes in the brain (Stein et al., 2010). While this process occurs regardless of age, the speed of plasticity directly correlates to the long-term proficiency of an individual (Stein et al., 2010). So, relative to the time I started learning French in 9th grade, my immersion experience these last six months has allowed my brain to greatly pick up speed in making physical and functional changes compared to my 15-year-old self.

Not only is the study of French language a passion, being bilingual (or as close as I’ll ever get) advances cognitive control meaning that bilinguals develop better decision making and conflict mediation skills than monolinguals, according to the bilingual cognitive advantage hypothesis (Bialystok and Barac, 2013). This development results from a bilingual’s ability to better monitor life-long experience, cultural sensitivity, and mentally separate and switch between two languages (Stein et al., 2010).

A study in 2011 tested the impact of bilingualism on conflict monitoring and found that bilinguals not only resolve cognitive conflicts more efficiently (meaning with less neural input), but that their brain also better sorts and makes sense of conflicting input (Abutelabi et al, 2011). Using a group of 17 highly proficient German-Italian bilinguals and 14 Italian monolinguals, researchers studied the anterior cingulate cortex (ACC), the brain center involved with language control and monitoring conflicting information, through blood flow measurements in a functional magnetic resonance imaging (fMRI) scanner. Participants were then asked to perform language and non-language switching tasks. For the language-switching task, monolinguals were presented with a set of 32 different pictures and asked to produce a noun or a verb associated with the picture based on a color-coded system (red for nouns and green for verbs). Bilinguals were then shown these same pictures, but asked to describe the picture in either German or Italian, per another color-coded system (green for German and blue for Italian). Researchers found that ACC activity was significantly increased in bilinguals. For the non-language switching task, the participants were presented with a cross in the middle of the screen to fixate their line of sight during the entire trial. Five arrows then appeared in randomized order and direction and the participants were asked to identify the direction of the center arrow only.

A schematic of the visual task presented (Albutelabi et al., 2011).

A schematic of the visual task presented (Albutelabi et al., 2011).

Here, the bilinguals required less ACC activity while still outperforming monolinguals in accuracy. These results show that bilinguals are more efficitvely and efficiently able to distinguish the direction of the center arrow surrounded by the swtiching stimuli.

I loved that this study incorporated both a language switching task and a non-verbal task, which shows that the two tasks were carried out by the brain in the same region and thereby lends credit to the idea that development of the ACC in the study of a second language has positive effects in other parts of our daily lives. However, I wish that Albutelabi et al. had used participants of varying degrees of proficiency to see if the bilingual advantage spans across any second language learner.

Independent of my improved ability to find the best pastry in Paris due to increased language proficiency, I hope that I will have gained a life-long advantage to greater health and mental acuity. Not only have Paris and my French studies given me a greater awareness and appreciation of the world, increased neuroplasticity will allow me to use these now more refined areas, giving me confidence to switch between subjects and focus in on information relevant to the task at hand. This will come in particularly useful in my pre-dental studies along with other future endeavors, as lifelong bilingual experience may serve as a major deterrent to the onset of age-related cognitive decline (Grogan et al., 2012).

I shadowed a French general dentist in the 11th arrondissement.

This semester, I shadowed a French general dentist in the 11th arrondissement.

As I end my time in this beautiful city, I will keep my experiences (and brand new brain) pour toujours.

~ Amy Yeh

References

Abutalebi J, Della Rosa PA, Green DW, Hernandez M, Scifo P, Keim R, Cappa SF, Costa A (2011) Bilingualism Tunes the Anterior Cingulate Cortex for Conflict Monitoring. Cerebral Cortex 22:2076–2086.

Bialystok, E., & Barac, R. (2013). The psycholinguistics of bilingualism. New York, NY: John Wiley & Sons, Inc.

Grogan A, Jones OP, Ali N, Crinion J, Orabona S, Mechias ML, Ramsden S, Green DW, Price CJ (2012). Structural correlates for lexical efficiency and number of languages in non-native speakers of English. Neuropsychologia 50(7): 1347-1352.

Stein M, Federspiel A, Koenig T, Wirth M, Strik W, Wiest R, Brandeis D, Dierks T (2010) Structural plasticity in the language system related to increased second language proficiency. Cortex 48:458-465.

Walking through Paris

Amongst the many changes I have experienced while in Paris, I noticed that I am walking considerably more than I usually do. While most people are aware of the positive impact walking and exercise can have on the body, I am dedicating this post to exploring the effects of exercise on the brain.

Thanks to my handy Fitbit (yes, I know I am a little obsessed), I am able to track my daily activity, so I have a very good idea about how much exercise I am getting. Between going to class, touring museums, and exploring getting lost in the streets of Paris, I am walking an average of over 8 miles every day. Paris is a very “walk-able” city, and my friends and I regularly opt to walk to our destinations instead of using the metro. I know that this must be affecting my cognitive ability, because even while operating on 4-6 hours of sleep every night, I am able to focus and work surprisingly well.

Fitbit evidence that 1) I am walking crazy amounts in Paris, and 2) I can justify eating multiple pastries a day*  *point 2 has not been scientifically proven

Fitbit evidence that 1) I am walking crazy amounts in Paris 2) I can justify eating multiple pastries a day*
*point 2 has not been scientifically proven

A recent study in college-aged females found that after only a single session of moderate exercise, participants showed increased brain activation during a working memory task (Li et al. 2014). Working memory is a limited brain resource that temporarily stores, processes and updates action-related thinking. It is utilized when you need to actively handle information, and your working memory capacity is an important measure of cognitive function. The researchers in this study used a modified N-back task to measure working memory. This task requires participants to attend to a sequence of stimuli, and determine if the current stimulus matches a stimulus that was “N” steps earlier in the sequence. The task gets more and more difficult as N increases, because it becomes harder to keep track of when a stimulus appeared.

A visual representation of the N-back task used in the study by Li et al. (2014)

A visual representation of the N-back task used in the study by Li et al. (2014)

To compare brain function, the subjects performed this task while in a functional magnetic resonance imaging (fMRI) machine, once following exercise, and once following a rest period. The fMRI measures blood oxygenation, which provides a visual image of brain activation. While there was no significant change in subject performance on the task, the data show more brain activation in the exercise condition, especially in the prefrontal cortex (PFC) and medial occipital cortex during the 2-back condition. The PFC is well recognized to be important for working memory, and the specific areas of the occipital lobe that changed are also involved in online processing. The lack of performance change limits the conclusions that can be drawn from this study, but it is reasonable for me to assume that my working memory capacity is positively influenced by the increased exercise I get in Paris. The researchers clearly showed that exercise influenced the brain areas important for working memory in subjects of my same age and sex, and this effect would likely be enhanced by an extended exercise routine like mine. A future study could explore the effect of chronic exercise, or use multiple behavioral measures to see if that leads to more pronounced changes in working memory performance.

Working memory is not the only brain function influenced by exercise. In fact, hundreds of studies explore how exercise can change the brain. One of the most common focus areas is how exercise increases brain-derived neurotropic factor (BDNF) in the hippocampus. BDNF is very important for brain plasticity, and the hippocampus is highly involved in learning and memory. One study found that exercise enhanced memory and cognition in rats, through the action of BDNF and the pathways it influences (Vaynman, et al. 2004). A different study focused on the non-neuronal cells in the brain, called glial cells (Brockett, et al. 2015). They found that running influenced synaptic plasticity in rats, producing widespread positive effects in both neurons and glial cells in areas associated with cognitive improvement. The last study looked at showed how exercise can help people’s mental health by reducing the stress hormone cortisol, through overall regulation of the hypothalamic-pituitary (HPA) axis (Zschucke et al. 2015).

I walked almost 10 miles before stumbling upon this set at Fete de la musique, and the journey was as fun as the event!

I walked almost 10 miles before stumbling upon this set at Fete de la musique, and the journey was as fun as the event!

It is so interesting to hypothesize about the different ways that my brain may be changing in response to something as simple as walking. Evidence suggests that my working memory capacity, brain plasticity, and mental health are all influenced by exercise. Now that I only have one week left to enjoy Paris, I will make sure to walk everywhere to experience, learn and improve my brain as much as possible. With all of the positive effects Paris seems to have, I know I will be planning a return trip the second I get home!

 

References 

Brockett AT, LaMarca EA, Gould E (2015). Physical Exercise Enhances Cognitive Flexibility as Well as Astrocytic and Synaptic Markers in the Medial Prefrontal Cortex. PLoS ONE. 10(5): e0124859.

Li L, Men W-W, Chang Y-K, Fan M-X, Ji L, & Wei GX, (2014). Acute Aerobic Exercise Increases Cortical Activity during Working Memory: A Functional MRI Study in Female College Students. PLoS ONE. 9(6): e99222.

Vaynman S, Ying Z, and Gomez-Pinilla F, (2004). Hippocampal BDNF mediates the efficacy of exercise on synaptic plasticity and cognition. European Journal of Neuroscience. 20: 2580–2590.

Zschyke E, Renneberg B, Dimeo F, Wüstenberg T, & Ströhle A (2015). The stress-buffering effect of acute exercise: Evidence for HPA axis negative feedback. Psychoneuroendocrinology. 51: 414-425.