Tag Archives: neuroscience


I knew from the minute I set foot into the French customs line at the Charles de Gaulle airport that perhaps I didn’t know French as well as I thought I did. Every conversation around me—except for the Americans’ I followed off the plane—sounded oddly like gibberish. In keeping with my nosy personality, I sidled a little closer to the French couple behind me to see if I could eavesdrop on a word or two—nada. One would think that five years of taking French classes would have gotten me a little farther than that.

Image Courtesy of Google Maps

I still remember my reaction in the first few minutes of French 201 at Emory. My professor greeted all the students in French when we walked in the door. Oh, that’s cute, I thought. But when 11:30 hit, class officially started, and she continued to speak in French, my mouth actually dropped open. How was I supposed to understand her? I could barely understand a word of spoken French. The nerve of my French professor to actually speak in French! Initially, the biggest thing on my mind was finding out a way to get the biggest bang for my buck in returning my newly purchased French textbooks.

Fortunately, a mix of procrastination in dropping the course and unyielding determination—a quitter I was not—led me to eventually decide to tough it out in French for the year. Good thing I did, because a few months later I would find myself in the largest French-speaking city in the world.

Setting foot in Paris a few weeks ago brought me right back to the feelings I felt the first day of French 201. As the weeks went by, I practiced, spoke to a few French natives, and most importantly, I listened. I started getting lost in the raw melodies of the French language—often I would find myself listening to the intonations of the speech rather than actually paying attention to what was said. I started comparing French to other languages, like English. Would a foreigner to the English language appreciate the melodies that are simply words to us? How does the brain process it? I know that there are some languages that have totally different basic sound units—can a person who is not native to the language even process those units? The budding neuroscientist in me had so many questions.

I looked up this super cool graphic from medical daily that basically told me that yes—language changes the way we think* For example, because there are more words for colors from dark to light blue in the Japanese language than in English, the Japanese perceive more colors than we do. Conversely, languages with fewer terms have the opposite effect—those native speakers perceive even less colors (Medical Daily). The ball doesn’t just stop at color perception—there are nearly infinite differences between languages that could change the way we think. Do these differences mean that the brain of one native language speaker is set up a little differently from the next? I wondered: Do differences in language between native speakers have any effect on the brain?

An article by Ge et al. (2015) asks how native speakers of different languages process that language—specifically Mandarin Chinese and English. Why did experimenters compare English with Chinese and not, say, the second best language on Earth—French? A part from English and Chinese being the two most widely used languages in the world, the Chinese language is a tonal language, meaning that the intonation used determines the meanings of the words. English, on the other hand, is atonal (hence the reason why high school geography teachers could get away with fully monotone class sessions). Researchers placed 30 native Chinese speakers and 26 native English speakers in fMRIs and used dynamic causal modeling (DCM)—which is essentially a way to construct a model on how brain regions interact. Our lovely subjects were presented with either intelligible or unintelligible speech in their native languages while being scanned, then data was compared between the two groups.

Classic language areas

Now, before we delve into the scintillating results of this study, let’s talk a little about how brain areas relating to language actually work. Most of language is processed in the left hemisphere of the brain. In this classic language area are structures like Broca’s area and Wernicke’s area, which are big names to the brain language nerds. Perhaps more relevant to this article is the pathway associated with the sound-meaning map, which assumes language-processing starts from the temporal lobe, goes to its anterior reaches, and ends up in the frontal lobe. In this paper, researchers think that this sound-meaning area will be more highly activated in native Chinese speakers, since their language relies so heavily on sounds and intonations for understanding speech.

Now for the exciting part: were the researchers right? They found that while the regions themselves that process speech are mostly the same across languages, the pathways through which these regions interact may be different. The brain areas commonly associated with language are the left posterior part of the superior temporal gyrus (pSTG), the anterior part of the superior temporal gyrus (aSTG), and the inferior frontal gyrus (IFG), which—for the purposes of this study—were named regions P, A, and F, respectively.

Essentially, data showed that when hearing intelligible speech, both the Chinese (tonal) and English (atonal) brain showed increased speech in the P to A areas—that’s shown by the green arrow on the first brain in the diagram below. Chinese speakers showed more activation than English speakers when listening to intelligible speech in both of the pathways coming out of the A area (red arrows in the middle brain). This may be due to further semantic processing that is needed for word identification in Chinese. This also happens to be one of the pathways for the sound-meaning map that we talked about before. So yes, the researchers were right in their hypothesis (big surprise)— the Chinese brain had more activation in this particular pathway than the English brain did. Finally, good ole’ English speakers showed more activation than Chinese when listening to intelligible speech in the P to F pathway (the red arrow on the final brain). This pathway is usually implicated in phonological speech processing (Obleser et al., 2007), where the first phonological features are usually enough to be able to identify words in atonal languages. Long story short, this data tells us that while there are common pathways used in understanding speech in both languages, some of the pathways between the brain regions are also different. To the big language nerds—and now to us—that’s pretty exciting stuff.

Figure 2A from Ge et al (2015)


What’s great about this paper is that it uses two languages that have really clear differences—tonal Chinese vs. atonal English. Scientific experiments are usually best with wide and clear-cut variables like those seen between English and Chinese, so the languages they tested for in this study were great. However, because of the way that this experiment was designed, we don’t know whether their main question—how is language processed in the brain by native speakers of a different language—really has anything to do with whether the subject was a native speaker or not. We don’t know if the pathway activation that we saw was due to a different general functioning of the brain in a given subject, or if it was due to the subject simply understanding a language that required certain pathways to be activated. In other words, is the difference in activated pathways due to the inherent way a native speaker’s brain works, or is it due to the pathways required to understand the language—regardless of the brain that’s doing the processing? In defense of the article, their question may not have been this complex. Maybe in the future, researchers could do a further experiment with native English speakers who also understood Chinese (or vice versa), and compare activated pathways when they heard intelligible Chinese to the pathways activated in a native Chinese speaker.

Either way, it’s definitely interesting to know that different languages require different brain pathways for processing. Maybe one day—preferably after an especially delicious Nutella crepe—the language pathways in my brain used for understanding French will become activated, and I can finally eavesdrop on all the airport conversations I want.





Image #2 from: thebrain.mcgill.ca


Crinion JT, et al. (2009) Neuroanatomical markers of speaking Chinese. Hum Brain Mapp 30(12):4108–4115.

Ge J, Peng G, Lyu B, Wang Y, Zhuo Y, Niu Z, Tan LH, Leff A, Gao J (2015) Cross-language differences in the brain network subserving intelligible speech. PNAS 112(10):2972-2977.

Obleser J, Wise RJ, Dresner MA, Scott SK (2007) Functional integration across brain regions improves speech perception under adverse listening conditions. J Neurosci 27(9):2283–2289.





Bonjour, Do You Speak English?


If you asked me what the hardest thing about living in Paris has been, my answer would be simple – the language barrier. Before leaving for Paris, I didn’t know any French besides how to say hello and goodbye. While I have picked up a few useful phrases in the past 4 weeks, it has still been very difficult to remember what I’ve learned. I began to wonder why I was having such a hard time with French, especially based on my previous experiences with language. When I was a young child, my mother used to teach me Chinese words and phrases. While I am nowhere near fluent in Chinese, I can still easily remember names of words and recognize phrases that I learned many years ago. On the other hand, learning French has been quite the struggle. I can spend a while reading my French traveler’s guide and practice my accent, yet hardly remember what I practiced the next day. Language is a very important field in neuroscience, so this experience led me to ask several questions: Why is it more difficult to learn a second language as we get older? Are there differences in anatomy of language areas in the brain depending on what age you learned a second language? While it is generally well known that children are able to learn languages much more quickly than adults (Johnson et al., 1989), I wanted to look further into how the age of learning a second language affects brain structure.

In 2014, Klein et al. published a study that examined how the age at which a second language is learned shapes brain structure. This study used four groups of participants: monolinguals who spoke only one language (monolinguals), bilinguals who learned two languages either simultaneously from birth or up until age 3 (simultaneous bilinguals), bilinguals who learned their second language from early childhood ages 4-7 (early sequential bilinguals), and bilinguals who learned their second language during late childhood ages 8-13 (late sequential bilinguals). All participants were interviewed and given questionnaires about their language background to determine which group they belonged to. It’s important to know that monolinguals were considered fluent only in their native language even if they received some formal training of another language, so taking a few years of Spanish in school doesn’t count as being bilingual. This study used magnetic resonance imaging scans (MRI), which allowed researchers to take an image of the brain and compare anatomical differences between participants’ brains.

Image: Cerebral Cortex, the outer layer of tissue in the brain that researchers measured for thickness

Animation: Inferior Frontal Gyrus Location (left side)

First, researchers tested for general differences in cortical thickness (how thick the outer layer of tissue in the brain was) using MRI between monolinguals and the different groups of bilinguals. They were interested in measuring cortical thickness to see exactly how being bilingual affects growth in language areas of the brain during development. A thicker cortex meant that there was more neuronal (cells in the brain) development in that brain region. Researchers found that there was a significant difference in cortical thickness between the groups in a brain region called the left inferior frontal gyrus (LIFG). The LIFG is very important for phonological and syntax processing in language (Vigneau et al., 2006). Phonological processing means using sounds to understand language, and syntax refers to understanding the order of words to form sentences. Researchers found that the LIFG was much thicker in the early and late sequential bilingual groups compared to the monolingual group. Put more simply, the LIFG was much thicker only in bilinguals that learned their second language after early childhood compared to monolinguals. These differences in cortical thickness were not surprising, since the LIFG is a key brain area involved in language processing. These results demonstrated that learning a second language after becoming fluent in the first language changes brain structure during development. This was very significant finding, because it shows the “plasticity” of the brain, or the brain’s ability to reorganize itself and form new connections in different environments! To explain why the cortex becomes thicker in early and late sequential bilingual groups, researchers suggested that learning a second language after early childhood causes neurons and connections between neurons to grow in brain areas involved in language.

Figure 1: Klein et al., 2014

MRI scans showed that there was no difference in cortical thickness between the monolingual group and the simultaneous bilingual group. This was another very important finding, because it showed that being bilingual only affects brain development when a person learns their second language after early childhood. Researchers reasoned that these differences in cortex thickness might mean that there are different learning processes involved in first and second language learning only when the languages are learned separately after early childhood. These different learning processes might cause the cortex in language areas to become thicker as neurons and their connections grow. These results also show that the age when learning a second language is very important for setting up the brain structures involved in language.

Neurons and their many connections

Once researchers determined general differences in cortex thickness between monolinguals and bilinguals, they wanted to further study the relationship between brain structure and age of language learning in the bilingual participants. They found that the later a second language was learned after an individual learned their first language, the thicker the cortex was in the LIFG. Based on these results, researchers suggested that that the thicker cortex associated with later second language learning might reflect the brain using less than optimal neural circuits for language learning. An easier way to think about the brain is by thinking of it as a huge switchboard with lots of connections between each area of the brain. A neural circuit is like a path that information follows to get from one part of the brain to another. There are neural circuits that are direct and very quick, but there are also more roundabout ways to send information from one area to another. As we mature, our brain begins to solidify its connections, so the neural circuits used when a second language is learned at a later age may not be as direct and quick. Using suboptimal circuits could contribute to the cortex becoming thicker, as neurons increase their connections to follow a roundabout path. Learning both languages at the same time during early childhood appeared to use optimal neural circuits for language learning, because there were no differences in thickness between monolinguals and simultaneous bilinguals.

I found this study to be very interesting because it showed that there are anatomical differences in language regions of the brain that depended on what age a participant learned their second language. It was also very informative because it shows that the brain isn’t a set in stone structure, and our environment can significantly contribute to our development. As a follow up for more concrete conclusions about neural circuits involved in language learning, I’d like to see a study where researchers measure activation of the LIFG rather than just differences in cortex thickness. For example, functional magnetic resonance imaging (fMRI) measures brain activity by detecting blood flow to specific brain regions. Participants could read or listen to their native language followed by their second language in an fMRI machine to measure and compare how much language areas of the brain are active. Results from this would be even more informative in understanding how the age at which a second language is learned plays a role in language processing. For example, variation in brain activity could confirm differences in optimal and suboptimal neural circuits depending on what age the second language was learned. This would allow researchers to understand more about how neural processing, rather than just anatomy, is affected in language areas by learning a new language.


Until next time,

  • Sarah



Johnson JS and Newport EL (1989). Critical period effects in second language learning: The influence of maturational state on the acquisition of English as a second language. Cognitive psychology, 21(1), 60-99.

Klein D, Mok K, Chen JK, & Watkins KE (2014). Age of language learning shapes brain structure: a cortical thickness study of bilingual and monolingual individuals. Brain and language131, 20-24.

Vigneau M, Beaucousin V, Herve PY, Duffau H, Crivello F, Houde O, and Tzourio-Mazoyer N (2006). Meta-analyzing left hemisphere language areas: phonology, semantics, and sentence processing. Neuroimage30(4), 1414-1432.

Cerebral cortex image (Creative Commons): http://www.neuroscientificallychallenged.com/blog/know-your-brain-cerebral-cortex

Left inferior frontal gyrus animation (Creative Commons): https://commons.wikimedia.org/wiki/File:Inferior_frontal_gyrus_animation_small.gif

Neural connection image (Creative Commons): http://maxpixel.freegreatpicture.com/Network-Brain-Cells-Brain-Structure-Brain-Neurons-1773922

French Phrasebook Image: https://images-na.ssl-images-amazon.com/images/I/51pqTbOV1qL._SX350_BO1,204,203,200_.jpg

Figure 1 from Klein et al., 2014

Our Brains Want Chocolate…Literally

Salut mes amis!

I have literally been waiting since the beginning of this trip for this one day. I’ll give you some clues: It’s sweet. It’s yummy. There’s a golden ticket involved. Do you know it yet? Willy Wonka’s chocolate factory!!!! Okay maybe not that exact one, but I’d say this comes as a close second. Just walking in immersed me in an air of chocolatey yumminess, and this was just the entrance with the gift shop. The excitement was literally killing me.

Le Musée Gourmand du Chocolat

Future Chocolatiers


I think I may just switch careers and become an Oompa Loompa. I mean chocolatier, or do I? Besides, I don’t see why not. I’ve already got my partner, Kara, and I got to say I think we make a pretty good team. With our piping, tapping, and scraping skills, I think we’ve got a solid business. So, if my whole neuroscience plan doesn’t work out, well you know where to find me.


Getting our blessings from the real master 🙂

Well, back to the chocolate making. First, we got to learn how to make the first layer of our molds with some creamy dark chocolate. By the way, they sort of looked like mini Patrick Star’s from SpongeBob. Anyways, after 15 minutes in the freezer, we added some hazelnut and milk chocolate as our center layer and set it back in the fridge. We topped it off with some more dark chocolate and voila! We had created a masterpiece! Très délicieux! Obviously, we weren’t professionals so it was unfortunate that we made quite a bit of an artistic mess on the table. So, to make up for our “accidental” spills, we were forced to clean it up by eating it all. It was tough, but we had to do what was right. I mean, we were simply following in the footsteps of our role models.

Our moms have become the kids…

As we made our way around the museum, I started to think about how chocolate affects our daily lives. Before every exam I have had since high school, I make sure to get some chocolate in my system. Even just a little Hershey kiss. It became a psychological thing for me, but it turns out, chocolate might have some neurological effects on us.

Making our mark everywhere we go!

Chocolate contains cocoa flavanols, which are antioxidants and anti-inflammatory agents with known benefits to our cardiovascular health. These chemicals seem to accumulate in the hippocampus, a region that is involved in memory and learning. It is believed that these chemicals interact with various signaling pathways in our brain that help process long-term memories (Sokolov, 2013).

The hippocampus plays a role in processing short-term memory to long-term memory

In a recent study, Mastroiacovo et al. (2014) looks at the effects of chocolate on cognitive function. They recruited 90 elderly individuals who were assigned to consume a drink containing cocoa flavanol every day for 8 weeks. This drink, somewhat like chocolate milk, contained either high, intermediate, or low flavanol concentrations and their cognitive function was assessed using various mental examinations at the beginning and end of the 8-week period. There was improvement seen in all three groups, and more significantly in the high and intermediate groups. This may be an effect of cocoa flavanols increasing the blood flow in the brain. This is important because our blood transports nutrients and fuel to our body, and by increasing its flow, we are able to deliver more “brain food”. Aside from neurological benefits, they also saw a decrease in blood pressure, cholesterol and insulin levels (Mastroiacovo, 2014). All the more reason to consume chocolate, right?

Since this study was done in elderly individuals, I would really like to see if the impact of chocolate would be greater if this type of routine were done throughout childhood. It would definitely give us kids more reason to go chocolate crazy. They also looked at other health improvements (e.g. blood pressure) in addition to cognition, which will encourage investigation of other physiological effects caused by chocolate. 

Presenting chocolate Patrick Stars



Moral of the story in my opinion: Never say no to chocolate! What’s the worst it can do, make you smarter?




À bientot!

Swetha Rajagopalan


Crichton, G. E., Elias, M. F., & Alkerwi, A. (2016). Chocolate intake is associated with better cognitive function: The Maine-Syracuse Longitudinal Study. Appetite,100, 126-132. doi:10.1016/j.appet.2016.02.010

Mastroiacovo, D., Kwik-Uribe, C., Grassi, D., Necozione, S., Raffaele, A., Pistacchio, L., . . . Desideri, G. (2014). Cocoa flavanol consumption improves cognitive function, blood pressure control, and metabolic profile in elderly subjects: the Cocoa, Cognition, and Aging (CoCoA) Study–a randomized controlled trial. American Journal of Clinical Nutrition,101(3), 538-548. doi:10.3945/ajcn.114.092189

Sokolov, A. N., Pavlova, M. A., Klosterhalfen, S., & Enck, P. (2013). Chocolate and the brain: Neurobiological impact of cocoa flavanols on cognition and behavior. Neuroscience & Biobehavioral Reviews,37(10), 2445-2453. doi:10.1016/j.neubiorev.2013.06.013

Images Retrieved from these sites:


Monkey See, Monkey Do

Thinking back to fifth grade field trips, the long lines, the sweltering hot Louisiana sun, and the teachers who thought that the visit would be the pinnacle of fifth grade achievement, I became accustomed to disliking trips to public places like zoos, museums, aquariums, etc. That being said, I never would have imagined finding myself paying 16.50 euros to go to a zoo here in Paris—yet there I was last Saturday, in that very position. Little did I know that that trip would become one of the most memorable ones of my first week in Paris.

Photo Courtesy of Google Maps


Parc Zoologique Sign


It all started when I met Bruce, a zebra in the zoo who I decided to name myself. There I was–staring at two especially unexciting rhinos and wondering to myself whether there were any animals in this zoo that did anything other than sleep through the day–when, as if on cue, Bruce appeared out the brush and proceeded to feast on a nearby tuft of grass. He was almost close enough to touch, the intricate patterning of his dust-covered black and white stripes catching my eye. Never in my young adult life would I think that I would be so excited to see a zebra, but there I was, gasping and aweing with the eight-year olds beside me.

Bruce and I


Bruce wasn’t the only new friend I made that Saturday afternoon. I had yet to see my favorite exhibit—the baboons. As I approached, the first thing I noticed was the large number of people watching from the viewing platforms. This must be a good one, I thought to myself. As I peered through the enclosure, I was surprised by their cacophonous action. There was always some baboon doing something hilarious somewhere in the cage—one chewing on some type of plastic, another swinging from tree to tree, yet another sitting up straight—quite peculiarly with its hands folded in its lap and looking like an old-time English professor.


The English Professor

However, I quite literally believe I got stars in my eyes when I caught sight of a newborn baboon with its mother. The baby—I named him Johnny—climbed on its mother’s back for a piggyback ride to the watering hole. When they arrived, Mom sat down, whipped Johnny around to her front side (her back to the viewing platform) and began breastfeeding. Soon enough, two other mothers arrived and started breastfeeding their babies, until there was a ring of nurturing mothers and their children. I was struck by the similarities in these baboons to human mothers—the way they cradled their children, the way they stroked their newborn’s fur as the baby suckled, the protective sidling of the mother whenever a male encroached into her area—with every minute I watched, I could see why these were our closest animal relatives.

Mothering Baboons


Being the budding neuroscientist that I am, I started to consider the brain mechanisms for this behavior. In almost every animal species, mothers innately care for their young—this obviously makes sense in an evolutionary perspective, but what are the brain mechanisms for this behavior? What motivates it? What is the neuroscience behind it all?

An article by Kikuchi et al. (2015) addresses the neuroscience of maternal love. The experiment was designed to look at the brain activity of young mothers when viewing video clips of their 16 month old infants showing attachment behaviors. Mothers in an fMRI were shown either a clip of their infant smiling at them while they played together (play situation—PS) or of their infant being in distress when the mother left the room (separation situation—SS). The researchers hypothesized that the parts of the brain mediating maternal behavior would be more activated when the infant was in distress (SS) than when the infant was not (PS). After the fMRI, mothers were asked to rate their subjective feelings (happy, motherly, joyful, warm, love, calm, excited, anxious, irritated, worry, and pity) in response to video clips in PS/SS of their own infants and of other infants.

So, what did the researchers find? There were four brain regions found to be specifically involved in feelings of motherly love: the right orbitofrontal cortex (OFC), the anterior insula, the periaqueductal gray (PAG), and the striatum. After identifying these brain regions, researchers then had to interpret what these results actually meant. Essentially, the OFC and the striatum are involved in the dopamine reward system, which would involve the mother’s motivation to care for her infant. The OFC, insula, and PAG are involved in an information processing system mediating homeostatic emotions for the mother and the realization of motherhood itself. Since the OFC is involved in both systems, it is thought to play an important role in mediating between the two.

Activated regions from Kikuchi et al.

Schematic of brain activation from Kikuchi et al.


After all was said and done, researchers found that mothers did, indeed experience higher brain activation in SS than in PS. As subjective ratings of worry increased in the SS, activity in the right OFC increased. Good to know that mom cares.

What’s great about this article is that it provides a simple and straightforward model of measuring brain activation of mothers in response to their babies. It asks the mothers’ subjective feelings in addition to the neurological aspects. However, it can also be said that this method might be too straightforward—mothers are undoubtedly faced with more than two situations of maternal love and attachment. Perhaps in the future, the authors could consider approaching a more complicated model—one with more situations like a feeding or a stress situation. Also, it is definitely a challenge to quantify love in a scientific aspect as these article attempts to do—perhaps it might be too poetic for such a field.

Poetic or not, there is an undeniable beauty in the way a mother cares for her child—whether that mother is human, baboon, or zebra. Either way you look at it, Johnny the baboon is certainly well accounted for.




Yoshiaki Kikuchi et al. (2015) The Neuroscience of Maternal Love. Neurosci Common 2015; 1: e991. doi: 10.14800/nc.991.

Photos taken by yours truly.



There’s Nothing Like the Smell of Home

Photo of the metro

About two weeks ago, I arrived very jet-lagged in Paris and couldn’t wait to explore the city. I wanted to take it all in – the sights, the sounds, and the smells. We hit the ground running during our first evening in Paris and rode the metro to the Eiffel Tower. As we waited in the metro station, I realized that I recognized the exact smell of the station. The dusty, metallic smell of the metro brought back many fond and vivid memories during my childhood where I often rode the metro in Toronto. I began to wonder why the smell of the metro brought back such vivid, emotional memories that happened over 10 years ago.

Balls at the museum that emitted smells when you picked them up!

Fast forward to several days ago, I experienced something similar in the Musée du Parfum (perfume museum). It is an amazing museum that is filled with lots of perfume and strong scents that we were able to sniff! One of the scents that stood out to me smelled just like a campfire. Similar to my metro experience, the strong smell of the burning wood brought back many great memories of roasting marshmallows around a bonfire at camp every year.

Fragrant roses at the museum



In the courses that I’ve taken as an NBB major, I have learned about the separate pathways in the brain that are active during olfaction, memory retrieval, and certain emotional responses. Interestingly, I have not yet learned what happens when those pathways interact like when an emotional memory is retrieved from an odor. I wanted to delve deeper and learn more about what is happening when memories and emotions are retrieved from odors.

Olfactory Pathway Diagram


It is already known that olfaction, memory, and emotion are closely linked in the brain. An olfactory signal is transmitted from the primary olfactory cortex to the amygdala and the hippocampus before being sent to higher order olfactory cortices (Shipley and Reyes, 1991). The amygdala is generally associated with emotional responses, while memory processes are closely linked to the hippocampus (Fortin et al., 2004; Cardinal et al., 2002). So, the olfactory signal is relayed through two brain structures that are important for both emotion and memory. 

In 2014, Saive et al. published a study that sought to better understand the interaction between emotion, olfaction, and memory. They tested the hypothesis that emotions invoked by odors facilitate the memory of specific unique events. To do this, they created a model to study memory and mimic real-life situations as best as possible in humans. Participants explored three laboratory episodes, each consisting of three unfamiliar odors (what), positioned at three specific locations (where), within a specific visual environment (which context). Participants explored one episode per day for three days, which they called encoding days. On the 4th day, called retrieval day, they were tested with distractor odors and the odors that they had previously experienced. The distractor odors were used to make sure that participants were associating the correct smells with their memory. Participants were asked to push a button if they recognized the smell, and then had to choose the specific location that they experienced the odor and the correct visual context. They also rated the odors based on pleasantness to investigate the influence of emotion on memory performance.

This study had several important findings that helped researchers better understand what was going on when participants retrieved memories from specific odors. First, they found that the number of accurately remembered contexts and locations was significantly higher when the odors were more pleasant or more unpleasant than neutral. This suggests that the intensity of the emotion  and the distinctness of the smell (but not pleasantness vs. unpleasantness) enhanced memory retrieval. This is what they expected to see – we are more likely to associate a memory that has emotional context with an odor than a neutral smell that we might experience every day.

Measured response times showed that the more information the participants remembered about an episode (what, where, which context), the faster they answered. Interestingly, the time period between odor recognition and retrieving details about their experience was constant no matter how accurate their retrieval was. Since there was no response time difference observed, researchers suggested that after odor recognition participants immediately recalled the whole episode at once rather than in pieces. Put simply, participants didn’t go step-by-step in their memory to recall where there were or how they were feeling, they instead remembered the entire memory at once. This led the researchers to propose a model to explain the cognitive processes that are involved in this unique memory retrieval. This model states that recognizing an odor and retrieving details about the memory associated with the odor are combined into a simultaneous memory retrieval process that begins as soon as an odor is smelled.

One strength of this study is that it mimicked real-life scenarios in the laboratory as naturally as possible by allowing participants to freely explore contexts with unique odors and ranging emotional valences. This makes the model suggested by the researchers more relevant to life outside of the laboratory and helps us better understand how odor is closely tied to memory recognition. Now I understand why I was able to quickly retrieve memories from so long ago just from a smell. Maybe many years from now, the smell of fresh baked bread will bring back fond memories of the many boulangeries (bakeries) I visited during my time in Paris.




Cardinal, R. N., Parkinson, J. A., Hall, J., & Everitt, B. J. (2002). Emotion and motivation: the role of the amygdala, ventral striatum, and prefrontal cortex. Neuroscience & Biobehavioral Reviews26(3), 321-352.

Fortin, N. J., Wright, S. P., & Eichenbaum, H. (2004). Recollection-like memory retrieval in rats is dependent on the hippocampus. Nature431(7005), 188-191.

Saive, A. L., Royet, J. P., Ravel, N., Thévenet, M., Garcia, S., & Plailly, J. (2014). A unique memory process modulated by emotion underpins successful odor recognition and episodic retrieval in humans. Frontiers in behavioral neuroscience8, 1-11.

Shipley, M., & Reyes, P. (1991). Anatomy of the human olfactory bulb and central olfactory pathways. In The human sense of smell (pp. 29-60). Springer Berlin Heidelberg.


http://www.cbc.ca/news2/interactives/brain/gfx/smell-pathway.jpg – Olfactory pathway diagram

https://pixabay.com/en/train-subway-tunnel-speed-1836126/ – Metro photo, Creative Commons

Photos at the museum – taken by myself

Chill, it’s just coffee!

Dear friend,

As I wrap up my last week in Paris, I’ve started noticing a peculiar number of coffee shops at just about every corner. Usually filled with people enjoying pastries accompanied with a small coffee, these cafés represent a snapshot of Parisian life. Outside of the café’s, people typically sit at the small but cleverly ornamented tables calmly and almost elegantly sipping on their simple beverage while reading the newspaper or chatting with a friend.

Cafes paris

Its so easy to find a café in Paris! (photo courtesy of google maps)

This isn’t anything like back at Emory, though! Unlike the sleep deprived college students at Emory who drink coffee as on-the-go rocket fuel, Parisians especially savor their brewed drinks as a vital part of their day. Nobody’s running around, on the go, fumbling with their food and coffee on the train, or spilling their drinks as they rush among pedestrians. This honor rests almost exclusively with American tourists, and in fact, remains as one of my surefire methods to find and befriend Americans in Paris!


Coffee in Paris

I should mention that I personally don’t enjoy drinking coffee this way, or in any way for that matter. I find it far too bitter and it seems that even if I can gulp it down with heaps of added sugar, caffeine and I don’t get along very well. It all started back in middle school when I drank a giant bottle of Pepsi during a back-yard soccer game (This would be forbidden at Emory, a school renowned for only selling Coke products on campus!). After about 20 minutes I felt a burst of energy as I sprinted down the field, but my heart raced, and my face got incredibly warm. Panicking about my racing heart, I ended up going to the hospital after the game, only to have the doctors tell me I was fine. Of course, by the time I got there, the effects of the caffeine faded. Since that experience though, I try to stray away from caffeinated drinks because of the side effects that come with it.

Tired and hot after soccer

Tired and hot after caffeine and soccer (www.drdavidgeier.com)


However, I recently participated in a small group-experiment as part of a project for our class that involved drinking coffee. As a willing participant, I bought coffee from the local café at Cité Internationale, and quickly drank one cup before completing a series of reaction time tests to examine the effects of caffeine on reaction time.

The coffees we drank for our experiment!

The coffee we drank for our experiments!


My reaction time increased, but interestingly so did my perceived body temperature and alertness. This got me thinking about the effects of caffeine on the body. How does this drug, available so readily throughout most of the world, affect the brain and body? Once again, equipped with Neuroscience, I turned to the Internet in my search for answers.

It turns out that caffeine works by blocking the activation of brain processes responsible for regulating sleepiness and fatigue. These processes normally activate when a certain neurotransmitter, adenosine, binds to a certain receptor, the adenosine receptor. When awake, adenosine builds up in the body and eventually binds to its receptor, signaling the body to sleep. Caffeine also binds at this site, but it binds without activating fatiguing processes, and just gets in the way of adenosine binding. By doing so, caffeine keeps its users energized (Fredholm et al., 1999). Previous research also indicates that caffeine increases dopamine release in the striatum, and nucleus accumbens, areas of the brain responsible for motivation, reward, and sympathetic nervous system activities typically known as fight or flight systems (Balthazar et al., 2009).


In a recent study, Zheng et al. (2014) tested the effects of caffeine on temperature regulation and neurotransmitter release in the preoptic area and anterior hypothalamus (PO/AH) of the brain, areas responsible for regulating body temperature. According to their study, researchers chose to study these areas because increased dopamine activity here leads to a better tolerance for heat storage in the brain and facilitates an increased metabolic rate (Balthazar et al., 2009). To investigate whether caffeine helps produce these enhancing effects, researchers measured temperature, oxygen consumption, and neurotransmitter presence in rats during rest and exercise states. In a total of 10 male winstar rats, Zheng et al. (2014) measured baseline serotonin (5-HT), dopamine (DA), and noradrenaline (NA) release in PO/AH using a microdyalisis probe or cannula for control. This tiny filter collected neurotransmitters and allowed experimenters to analyze measurements. To further test for temperature and oxygen consumption, researchers measured core and tail skin temperature in the same spot for all rats, and oxygen with an oxygen/carbon dioxide measuring box. One hour before rats were placed in the box to run on a treadmill until fatigue at an 18m/min pace, investigators intraperitoneally injected (injected into the abdomen) rats with saline, 3mg/kg caffeine, or 10mg/kg caffeine. (See Link1 at the bottom for a video of rats running on a treadmill!)

Oxygen/Carbon Dioxide measuring mechanism (www.pt.kumc.edu:research:diabetes-research-lab:RatTreat01)

From their data, Zhang et al. (2014) found that at rest, 3mg/kg caffeine levels did not result in any significant changes. However, at 10mg/kg, caffeine caused significantly higher core and tail temperatures, higher oxygen consumption, and extracellular DA and NA in the PO/AH. Data also showed that caffeinated rats showed increased endurance, and could run longer before fatigue set in. The researchers interpreted this to mean that caffeine facilitates dopamine pathways in the brain that lead to physical enhancements, specifically by modulating the PO/AH in a way that allows the brain to work under higher energy levels. I personally think of this as caffeine rearranging the brain’s thresholds for what we consider a state of exhaustion, and increasing energy consumptions by resetting the thermostat so we can function at a higher level. I  particularly chose this study  because the comprehensive testing used in the methods mimics these same high stress functioning levels I experienced while playing soccer.

I think as a whole the findings are incredibly interesting, and in my opinion, make perfect sense when interpreted this way. However I think that the researchers should definitely have included more details on the effect of caffeine on heart rate, as well as more incremental investigation on the effects of caffeine doses between 3 and 10 mg/kg. I would also like to see a larger sample size, or at least more than one trial per rat, as a sample size of 10 makes it difficult to collect meaningful data. I also wonder though, how long can this high energy state last before burning the body’s metaphorical engines? Perhaps future studies could test the effects of chronic caffeine use on prolonged energy levels.

As I continue my time in Paris, it feels great to see scientific explanations for everyday events. This past spring, I remember seeing a “contains caffeine” label on one of my running snacks when I ran a marathon. At the time, I thought that caffeine simply keeps you more awake, but little did I know that it facilitates increased endurance levels!

coffee chews
Caffeine chews

I’m glad neuroscience keeps sneaking up on me, pleasantly surprising me with answers. Who would have known that it would answer my childhood questions and help me chill out about coffee’s side effects.

For now, maybe coffee is not all that bad.

Here’s to new experiences and breaking out of my comfort zone!

Until next time,




Balthazar CH, Leite LHR, Rodrigues AG, Coimbra CC (2009) Performance-enhancing and thermoregulatory effects of intracerebroventricular dopamine in running rats. Pharmacol Biochem Behav 93:465–469

Fredholm BB, Bättig K, Holmén J, Nehlig A, Zvartau EE (1999) Actions of Caffeine in the Brain with Special Reference to Factors That Contribute to Its Widespread Use. 51.

Zheng X, Takatsu S, Wang H, Hasegawa H (2014) Pharmacology , Biochemistry and Behavior Acute intraperitoneal injection of caffeine improves endurance exercise performance in association with increasing brain dopamine release during exercise. 122:136–143.

Link1: https://www.youtube.com/watch?v=PxH0SBjteuc

Making Chocolate like a Pro

Have you ever watched a circus performer juggle for hundreds of people or a master chef expertly flip an omelet? Have you ever seen an elegant display of technique that takes some people years to master and thought to yourself: “yeah I think I can do that”? Well maybe you haven’t, but last week during our visit to the Musée de Chocolat, I had this experience.

Ok maybe not that exact thought process. In truth, when the master chocolatier asked the group: “ok who wants to try,” it was more along the lines of: “yeah, let’s see what happens.” As I took the triangles in my hands I really had no idea what I was doing, but after a small point of clarification, my hands started mixing the chocolate exactly how I had seen him do it. In fact it was going so well that he turned to me and asked: “have you done this before?” To which my reply was simply: “nope.”

Blog 2.1

Blog 2.2

The workshop continued in much the same manner where he would show us how to do a step in the chocolate making and I would reenact exactly what I had seen. Afterward I started wondering how a motion so complex could come so naturally to me.

A recent study has analyzed the role of the action observation network (AON), a network of sensorimotor regions in the brain, in the presence of familiar and unfamiliar actions (Gardner et al., 2015). The researchers asked the participants to watch a short video of dance moves and at the end of it, were asked to pick which of two options should follow in the sequence. The control group was asked to follow the dot sequence that was displayed on the same videos and afterwards had to choose which color was the last one pictured. For the duration of the test, participants were in an fMRI machine so that the investigators could record their brain activity. After the testing and recording, the participants rated the familiarity of the actions in the videos.

When Gardner and his colleagues examined the brain scans of each participant group, they found that the action-focused group showed greater activation in their motor cortices than the dot-focused group. Additionally, the more familiar tasks resulted in increased activity in the AON. The researchers then tested for the connectivity between the inferior parietal lobule (IPL), the middle temporal gyrus (MPG), and the inferior frontal gyrus (IFG) and from these tests developed a working model of how this system works in the presence of familiar motion stimuli.

Blog pic

The IFG and MTG receive input from the movement stimulus and relay this information back to the IPL. The connections between these three regions can also be modified by familiarity by a currently unknown pathway.

Now let’s return to my example of chocolate making (mmm… chocolate…). When I watched the professional chocolatier scraping the chocolate around the marble, the movement triggered the AON in my brain. Even though I had never performed this particular action, I have had many years of experience cooking and it is likely that this somehow contributed to the “familiarity modulation” the study discusses ultimately allowing me to make delicious chocolate with my friends.

blog map

-Kamin Bouguyon


Gardner, T., Goulden, N. & Cross, E.S. (2015) Dynamic Modulation of the Action Observation Network by Movement Familiarity. The Journal of Neuroscience, 35, 1561-1572.

Twenty-one and trying to keep it sober

To an American, turning twenty-one means more than adding a hyphen to your age. On June 8th, I got a call from my parents back in Rhode Island not only to wish me a happy birthday but also to pass along several warnings about what everyone associates with a twenty-first birthday: alcohol.  “We trust you,” they said, “but make good decisions!”

Cake 2IMG_1870


My birthday week, however, played out nothing like my parent’s expected.  I received three fantastic birthday cakes and dozens of birthday wishes, visited the beautiful town of Blois, France and the Versailles castle, and witnessed an unbelievable circus performance at Le Folies Bergere. Alcohol didn’t interest me, and for a moment I thought my parent’s advice about alcohol didn’t apply to me this trip.  After our group took an excursion to Le Musee Gourmand du Chocolat, a chocolate museum complete with a chocolate workshop and demonstration, I realized that I should have applied my parent’s advice  applied to my chocolate eating habits, not my first glass of wine. If I eat more than a few Hershey’s Kisses worth of chocolate I experience symptoms like coughing, temporary tightening of the throat, migraines, dizziness, and light-headedness.  Over the years, I learned to live with this food sensitivity, and yet, finding myself surrounded by chocolate during the excursion did nothing to curb my cravings.  As I usually do when offered chocolate, I ate far over my limit and dealt with my pounding head at the end of the visit.


I may have a chocolate problem–I might go as far as calling myself a chocoholic–but I’m not alone.  Chocolate is one of the most craved foods in the United States (Heatherington and Macdiarmid, 1993).  Although studies with dark chocolate suggests it can lower blood pressure (Ried et al., 2010), over-consumption of it can lead to health deficits like weight gain, or in my case, headaches and sore throats.


A: Blois, France B: Versailles, France C/D: The Chocolate Museum and circus within Paris

A: Blois, France
B: Versailles, France
C/D: The Chocolate Museum and the Kermezzoo circus within Paris

A study by Kemps et al. in 2012 offers a way to curb chocolate cravings through our sense of smell.  In their experiment, they asked 67 female undergraduates between the ages of 18-35 to look at 30 images of 10 different kinds of chocolate food such as cakes, bars, and ice cream.  Each image was shown for 5 seconds with a delay after the image.  During the delay, participants continued to imagine the image they saw in an attempt to produce a cravings for it (Kemps et al., 2005).  During the delay, the participant also smelled a bottle with the scent of water (the control), jasmine (a non-food smell), or green apple (a food smell), then rated their desire for chocolate.  The data collected showed that when participants smelled jasmine, their desire for chocolate was at its lowest.

The teal area shows the cingulate cortex, activated by chocolate consumption during the experiment by Small et al. in 2001.

This study was the first of its kind to link non-food odors as a useful means of suppressing chocolate cravings, but what happened in the brains of these participants?  Another study by Small et al. in 2001 analyzed the brain’s motivation to eat chocolate and found that the anterior cingulate cortex in the brain starts to becomes active when you take that first bite of chocolate and stays active even when you’ve eaten enough chocolate that it becomes averse.  A different study by Small et al. in 1997 showed that stimulating both our taste and smell sensations activates limbic brain areas, which include the cingulate cortex mentioned above.

Some of many brain areas associated with chocolate eating, smelling, and motivation.

Some of many brain areas associated with chocolate eating, smelling, and motivation.


With these two studies in mind, how does all of this fit into the chocolate craving antidote discovered by Kemps et al.?  If together smell and taste can activate the cingulate cortex and the anterior portion of the cingulate cortex is involved with our motivation to eat chocolate, then smelling a non-food smell like jasmine may be blocking something along that processing pathway between chocolate consumption and our motivation to each chocolate in the cingulate cortex.


Of course, this is just my own speculation.  Kemps et al. did not go into further detail about why jasmine effect on the brain our desire to eat chocolate, if jasmine is the only odor with this effect on chocolate cravings, or if jasmine an suppress cravings for other foods.  The study also focused on only one age group and one sex, therefore its results may not seem significant this field until other researchers conduct follow up research.  Regardless, this still an intriguing study in how it offers a potential therapeutic for women who have problematic chocolate cravings or other eating disorders.  Not only that, but maybe it could help people like me who simply don’t want to give up eating something that tastes so wonderful.

-Nicole Asante


Kemps E, Tiggemann M, Bettany S (2012). Non-food odorants reduce chocolate cravings, Appetite 58(3):1087-1090.

Ried K, Sullivan T, Fakler P, Frank O, Stocks N (2010). Does chocolate reduce blood pressure? A meta-analysis, BMC Medicine 8(39).

D Small, Zatorre R, Dagher A, Evans A, Jones-Gotman M (2001). Changes in brain activity related to eating chocolate: From pleasure to aversion, Brain 124:1720-1733.

Small D, Jones-Gotman M, Zatorre R, Petrides M, Evans A (1997). Flavor processing, NeuroReport 8 (18):3913-3917.



Café au Lait to get Through the Day

My amazing “café au lait” from Coutume Café in the 7ème arrondissement


Who doesn’t love a nice, hot cup of coffee after a morning shower? Not only does it taste AMAZING, but it also wakes you up and gets you ready for the day to come. Every morning, for the last 4 or so years, I drink a cup of coffee while getting dressed or eating breakfast. So, upon coming to Paris, I undoubtedly continued my ritual.

The walk from Cité Universitaire (where I live) to Coutume Café (my favorite coffee shop).




I essentially used my love of coffee as an excuse to visit as many cafés and small restaurants as possible. However, I soon discovered the enormous difference between French coffee and the American coffee that I am used to. The French are huge advocates for espresso, that is, a coffee-like drink served in tiny porcelain cups. However, unlike American coffee, espresso is extremely potent and filled with a TON of caffeine. Over the past few weeks, I too have become a lover of espresso and the large amount of caffeine and “energy” that comes with it. However, I was not quite sure exactly how caffeine affects the brain resulting in what we perceive as a boost in energy and decrease in drowsiness. So, throughout my days in Paris, I looked for an answer.

Typical French coffee (left) vs. typical American coffee (right)

While searching for an answer, I stumbled upon an article by Lazarus et al. (2011) concerning the effects of caffeine on wakefulness. Previous research found that caffeine counteracts fatigue by binding to adenosine A2A receptors. Adenosine, an inhibitory neuromodulator, has been linked to regulation of the homeostatic sleep drive. So, by binding to the receptor in the brain that normally binds to adenosine, caffeine indirectly prevents adenosine from functioning properly, altering one’s sleep pattern (Huang et al., 2011). Lazarus et al. used this information to construct their experimentations.

In their study, Lazarus et al. bred a strain of rats that had a knockout of the A2A receptor in their nucleus accumbens, that is, these rats did not have this receptor within this specific brain region. They then performed EEG (electrical monitoring) tests on these rats and compared their electrical brain activity with that of control rats (rats that did not have the A2A knockout). The researchers administered equivalent concentrations of caffeine to both groups of rats and monitored their brain’s electrical activity during sleep cycles. What they found was extremely interesting. The caffeine caused increased wakefulness in the control rats (those that did not have the A2A receptor knockout), while caffeine had no effect on wakefulness in the experimental rats (those with the A2A receptor knockout). This means caffeine not only blocks adenosine from binding to the A2A receptor (Huang et al., 2011), but it also prevents the activation of the “adenosine break,” resulting in increased wakefulness.

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A figure from Lazarus et al. (2011) depicting the adenosine A2A receptors in the nucleus accumbens of rat models. The left shows a control (wild-type) rat nucleus accumbens, while the right shows an experimental (knockout) rat nucleus accumbens.

Furthermore, the data from this study suggests that caffeine induces arousal and wakefulness by activating pathways in the nucleus accumbens that have formerly been associated with locomotion and motivational behaviors. This is a novel finding because it implicates caffeine in more than just the blocking of adenosine, but also in the activation of further neuronal circuitry, promoting a sense of “energy”.

A figure from Lazarus et al. showing the effect of caffeine on wakefulness. There is no significant increase in wakefulness in the A2A receptor knockout mice as more caffeine is administered. However, there is a significant increase in the wakefulness of wild-type mice as more caffeine is administered.

What I find super interesting about this study is how the researchers localized the antagonist effects of caffeine to the nucleus accumbems. In previous neuroscience classes, I learned of the association between the nucleus accumbens and cognitive processes such as motivation, pleasure and reward, thus implicating this brain region in numerous forms of addiction. With this in mind, I wish the experimenters had monitored the changes in behavior between the experimental and control rats when receiving differing levels of caffeine. This could be accomplished by using an intravenous self-administration task (IVSA). IVSA entails using chambers with small levers that, when pushed, cause specific drugs to be administered into the tail of that rat that pushed the lever (Figure 1). The researchers could perform IVSA for both control and experimental rats, and use either a saline or a caffeine solution as the respective drug. If this was done properly, I predict the control rats to show increased pushing of the lever when receiving caffeine compared to saline, corresponding to an greater feeling of pleasure and reward associated with the caffeine. Alternatively, I predict the experimental rats to show no significant difference in pushing of the lever between administrations of caffeine and saline because the caffeine does not affect their nucleus accumbens in the same way that it does for the control rats.

A very simplified version of the IVSA task in rat models.


Regardless, I find the study by Lazarus et al. to be extremely fascinating because, as a regular coffee drinker, it gives me insight to what is occurring in my brain!

Anyway, I’m about to go grab a coffee and walk around the city. Until next time!

~ Ethan Siegel



Huang ZL, Urade Y, Hayaishi O (2011) The role of adenosine in the regulation of sleep. Curr Top Med Chem 11:1047–1057.

Lazarus M, Shen H-Y, Cherasse Y, Qu W-M, Huang Z-L, Bass C, Winsky-Sommerer R, Semba K, Fredholm B, Boison D, Hayaishi O, Urade Y, Chen J-F (2011) Arousal effect of caffeine depends on adenosine A2A receptors in the shell of the nucleus accumbens. The Journal of Neuroscience 31(27): 10067-10075

The chocolate adventures of a chocolatier’s daughter in Paris

Chocolate. Chocolate. Chocolate. I can’t even begin to describe how much I love it. To give you guys a bit of context on my never-ending craving, my mom started a chocolate company while I was growing up. On a daily basis, my whole house smelt of freshly rolled truffles, baked brownies and chocolate cookies. Now, everywhere I go, I need to make sure that I have chocolate available at all times.   In my Parisian dorm room, I have at least five chocolate bars in stock. The satisfactory feeling of biting into a creamy piece mid-essay is unbeatable.

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Map of some of the best boulangeries in Paris

Walking around Paris, I love to stop at boulangeries and try whatever they have to offer, chocolate style. Some of my favorites so far include pain au chocolat, opera cake, and chocolate crepes. I recently spent the afternoon vising my brother and his wife in Belgium, and was in chocolate heaven. The Belgian chocolate brownie I had was life changing. My chocolate adventures continued this past Friday when I went to Le Musée Gourmand du Chocolat in Paris. It was quite the delicious experience; I indulged in cinnamon hot chocolate, praline, and other rare chocolates from all over the world. Best afternoon yet.


Me at Le Musée Gourmand du Chocolat

My current neuroscience mindset made me start to wonder how my chocolate cravings translate to brain activity. In a study by Frankort et al. the researchers studied the short-term effects of chocolate cravings on behavior, specifically how neuroimaging can predict chocolate consumption. The two different experimental groups consisted of participants who smelt chocolate and participants who didn’t, with 17 females in each group. They compared self-reported craving to brain activation showed by fMRI scans which measures the change in blood flow in different brain areas. Previous studies have found that prolonged chocolate exposure, like the chocolate scent group, leads to a decrease in craving. This effect was not observed in the Frankort et al. study; perhaps because the fMRI scan interrupted the 1-hour scent exposure sessions, which displays a weakness of the study since the interruptions don’t accurately model a real life situation.

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Brain activation in areas correlated with chocolate intake. Green: whole group anterior PFC activation, Yellow: exposed group caudate and frontopolar cortex activation, Purple: control group dorsolateral PFC and mid-dorsolateral PFC reduced activation.

Primarily, Frankort et al. found that neural activation in the right caudate and the left lateral frontopolar cortex predicted chocolate intake in the exposure group. The left lateral frontopolar cortex and the right caudate are both associated with reward and memory (Pochon et al. 2002), which explains the chocolate consumption. Furthermore, the left dorsolateral and mid-dorsolateral prefrontal cortex (PFC) correlated negatively with consumption in the control group, meaning the activation predicted decreased intake. These findings make sense since this area is associated with cognitive control (I would guess that I don’t have a very active left and mid-dorsolateral PFC when it comes to chocolate consumption). In both groups, the right anterior PFC, activation was associated with chocolate intake. This region is associated with cognitive behavior, planning and decision making (Wikipedia).

These regions of activation represent a better measure of future chocolate intake than self-reported craving, meaning that my brain knows I’m going to crave chocolate better than I am consciously aware of! The most surprising fact from this study was that overall self-reported chocolate craving did not correlate with intake. Meaning, just because I think I crave chocolate doesn’t mean I necessarily crave it. To really know if I crave something I would have to check my brain scans! A significant weakness of this study was how craving was measured by asking participants one question. Future studies should include a more appropriate measure of craving with multiple questions, since just having one may not fully explain the results.

This newfound knowledge on self reported craving has definitely made me rethink my chocolate consumption. Is a craving really a craving without brain activation? Whatever the answer to this question, I’m going to eat all the chocolate I can in this last week! Maybe I should rename the program title to Neuroscience, Chocolate and Paris.


Me eating un pain au chocolat


Me eating a chocolate cake











Frankort A, Roefs A, Siep N, Roebroeck A, Havermans R, Jansen A. (2015) Neural predictors of chocolate intake following chocolate exposure. Appetite. 87:98-107

Pochon JB, Levy R, Fossati P, Lehericy S, Poline JB, Pillon B, Le Bihan D, Dubois B (2002) The neural system that bridges reward and cognition in humans. An fMRI study. Proceedings of the National Academy of Sciences of the United States of America. 99: 5669–5674

Map: http://www.quora.com/What-are-the-best-boulangeries-and-patisseries-in-Paris-for-each-arrondissement