Category Archives: Neuroscience

If the Heat waved, would you wave back?

Posted on June 25, 2017 by | 6 comments
  1. Salut!

If you’ve read my first post, you already know I am not your common happy blogger… But don’t get me wrong, I LOVE PARIS and I’m having the time of my life!!!

So lets get started…

I landed in Paris a day before the start of the program, and stayed with my dad’s friend for a day. When I entered their house, I was shocked to see no central air conditioning unit, but I assumed they obviously have ACs in the bedrooms because isn’t it a necessity? Little did I know, ACs are not common in Paris, in fact, they are not “needed” because the weather is so pleasant. Coming from America, I guess you can say I am spoiled because I am used to being surrounded by air conditioning all day, everyday. From my home, to my car, to my school – it’s everywhere. Hence, I wasn’t consciously thinking of it as luxury but rather as a necessity.

Honestly, this is so relatable…

At Cite Universitaire, my room has a huge window that I normally keep open so that the temperature stays moderate, but even then I could not adjust to this non-AC lifestyle. After a few sleepless and irritated nights, I went and bought a fan; this was no doubt one of my best investments. That night, I slept like a baby.

The peaceful nights did not last very long though… This week, my third week in Paris, has been incredibly hot. The temperature went up the roof – about 35°C (95°F) average for the week. The authorities in France officially laid out precautions and plans to minimize the affects of this heatwave (thelocal.fr).

The temperature spiked around the 17th of June and returned to bearable temperatures on Friday!

 

As a person who already doesn’t like summer because of the unbearable heat, this was a very tragic week. I was sweaty, upset, annoyed, stressed, and tired all the time.

Those few moments of air conditioning or fan in some metros or restaurants were the moments I cherished. Coming back to my room everyday wasn’t something I looked forward to. Even my incredible fan wasn’t of much help with this heat.

With all these emotions and feelings I was going through, I wondered how this is affecting my brain (mainly because I needed a scapegoat to blame my unproductivity on – don’t judge).

As I dug deeper into the literature, I stumbled upon this article by Jiang et al. (2013) that investigated the effects of hyperthermia on human cognitive performance, using functional magnetic resonance imaging (fMRI), which is a technology used to detect changes in the brain activity during a specific task. Hyperthermia (HT) is defined as a condition in which the body temperature rises above normal. They wanted to see if cognitive performance would deteriorate in the HT condition compared to the control and how brain activity will be different in both groups.

The participants were divided into two groups; the HT group and the control group. To stimulate effects of hyperthermia, the HT group was in a hot chamber (50°C) with a thermal heated suit on for 30 minutes prior to the fMRI scanning. In the control group, the participants followed the same procedure but the chamber temperature was kept normal (21.5°C). The researchers precisely looked at brain activity during a visual short-term memory (VSTM) task to examine the participants’ cognitive performance. Previous research has shown three brain regions, dorsolateral prefrontal cortex (DLPFC), inferior intra-parietal sulcus (IPS), and intra-occipital sulcus (IOS), are involved in maintaining visual information for a short period of time (Todd et al. 2004, Grimault et al. 2009), hence, the researchers in the current study looked specifically at changes in activity in these three brain regions during the VSTM task.

In this task, the participants were presented with 60 trials of probe and target images, alternatively. Their task was to press “yes”, if the probe and target images were identical, or press “no” if the probe and target images were not identical. The participants in both the groups, control and HT, were in the fMRI scanner while they performed this task. Analyzing the behavioral results, they found that even though the HT group did not differ in accuracy compared to the control, they took much longer to answer the questions. On the neural side, fMRI results indicated increased brain activity in areas that are involved in visual memory task, as mentioned earlier (DLPFC and IPS). They saw that the brain was much more active during the heat exposure condition even though the participants were slow in the task, which shows that their visual short-term memory function was weakened. The researchers suggest that the increased brain activity could be due to more attention and cognition being used to do the same task compared to the control condition.

This study shows that exposure to very high temperatures, even for 30 minutes, can actually affect your cognitive performance. Your brain will need to use more energy and require longer time to perform a basic task. This study does an amazing job connecting the behavioral aspect with the neural aspect under heat stress in humans. It also uses well-defined brain regions, which makes it clearer to identify the changes in brain activity. However, they fail to discuss why they did not see changes in activity in IOS, one of the regions they evaluated during the tasks, even though previous research had shown that the IOS is involved in the visual memory task. More research needs to be done to identify how other cognitive activities may be affected due to heat, because global warming is a real problem and we see more and more incidents of heat waves occurring all over the world. If we better understand the impacts of heat on human brain and function, we can probably identify ways to prevent or rescue the damage caused by heat exposure.

Stay cool 🙂

Mehtab Manji

 

 

 

 

References:

Grimault S, Robitaille N, Grova C, Lina JM, Dubarry AS, Jolicoeur P (2009) Oscillatory activity in parietal and dorsolateral prefrontal cortex during retention in visual short-term memory: Additive effects of spatial attention and memory load. Hum Brain Mapp 30: 3378–92.

Jiang Q, Yang X, Liu K, Li B, Li L, LI M, Qian S, Zhao L, Zhou Z, Sun G (2013) Hyperthermia impaired human visual short-term memory: An fMRI study. Int J hyperthermia 29(3): 219-24

Local, The. “Paris: Authorities Trigger Emergency Heatwave Plan as Capital Continues to Sizzle.” The Local. The Local, 20 June 2017.

Todd JJ, Marois R (2004) Capacity limit of visual short-term memory in human posterior parietal cortex. Nature 428:751–4.

Images:

1, 4) http://www.welikela.com/heat-wave-memes-about-los-angeles/

2) http://www.funnycaptions.com/tag/summer-heat-jokes/4/

3) https://www.timeanddate.com/weather/france/paris/historic

 

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Posted in Neuroscience, Uncategorized

Bonjour, Do You Speak English?

Posted on June 25, 2017 by | 3 comments

 

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

 

References:

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 language, 131, 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. Neuroimage, 30(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

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Posted in Neuroscience

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Quote

The Unfamiliar Familiarity

           I like to think of myself as international2. I was born and raised in Honduras, and went to the United States for college. Now that I’m in France, I’ve been able to draw interesting parallels and contrasts between Honduran and U.S. culture to Parisian culture.

Map of Central America, Honduras in red-pink. I’m from Tegucigalpa, the capital.

View of the town I spent most of my weekends growing up with my family.
Cedros, Honduras.

 

Freshman year at Emory, and my now 2nd home.

 

Something that worried me before my trip was hearing how unfriendly to strangers French people are. I thought the U.S. was already unfriendly compared to home, so for the U.S. to consider the French unfriendly meant I would have the hardest of times making myself comfortable in Paris.

 

Turns out people were wrong. I feel that French people are even friendlier than in the U.S. Their friendliness is just a different kind of friendliness we’re used to at first glance. But once you open up with a fact about yourself or ask about them, the French are as open and willing to help you out as Hondurans would.

 

The Unfamiliar

When I first arrived, I could see what people meant. The metros are crowded places where you stand 10-25 minutes literally an inch (or less) apart from people, but they don’t even look at you. It felt so…awkward. In Honduras, I’m used to not only smiling but also greeting every passerby. In the U.S., I at least get to smile at people if we make eye contact. In France, both of these are not only rare, but make you feel weird and ignored. It wasn’t until I got here is that I learned that French people save their smiles for those they know…

 

As you can see…it’s pretty tight in there.

 

The Familiar

I was surprised to discover how well along I got with the French. The same kind of people I had to force myself to not smile to in metros were the same people I ran into in cafes and whom I could dance the night away.

I distinctly remember going to a small café near Cité for food since I had lost track of time and the cafeteria had closed. I was originally planning to go to a bigger café named Le Comptoir I had found on Yelp, but the road that one had closed off already. So I ran into this tiny restaurant/bar on my way around the park. It was pretty small, just having about 5 tables total. But I was pretty hungry, so I sat down and ordered whatever I could tell had meat on the menu.

 

I finished eating as the restaurant closed. Swing music started playing, couples started coming in, and dance moves started being rehearsed. I loved to see how the once dull and empty place filled with color, laughs, and music. Even the owner started opening himself up to me. He gave me free cheese and coffee. I talked to him a bit in Spanish. And I smiled at seeing how the tiny restaurant I had been in quickly turned into a dance floor.

 

These people looked so different from those at the metro. I not only talked to people, I even danced with them. The French laughed, were loud, and yes, smiled real big. Their liveliness reminded me of my Hispanic culture. I wondered how everything could change in a blink of an eye in this city. Especially the people themselves.

The Why

So I started getting curious. It seemed like a paradox to me. I knew from NBB302 that smiling is a universal human emotion (Gazzaniga 2013). I also knew that it took more energy and muscles to frown than to smile (Gazzaniga 2013). So why were the French so serious in crowded places, when I now knew from experience how warm and cheerful they really are?

Turns out how much you smile and even how you smile varies depending on where you are from. The more immigration your country has had during the last 500 years, the more you smile (Cesare 2013). People who are used to ‘melting pot cultures’ are used to going against their gut feeling fears of people that look different from them (Cesare 2013).

This immediately makes me think about the amygdala. The amygdala activates when we see faces of people that look different from us (Constandi 2012). The amygdala processes our emotions (Constandi 2012).

Location of amygdala (emotion processing) and hippocampus (memory).

 

Our brain naturally makes associations between how people look and the world around us. For example, most French people I talked assumed I was American simply because I looked different from them. This would trigger different associations they would later admit to me having about Americans. This is where their amygdala (emotion) and hippocampus (memory) would come in. Evolutionarily, our brain has developed to pay special attention to things and people around us that are different from us, since they could have been potentially harmful in the past (Rychlowska 2015).

 

However, in our modern interconnected world, we have learned to go against our gut feeling. So what stopped the French owner from assuming I was an annoying tourist and listen to my story?

Interaction between the amygdala, hippocampus, anterior cingulate cortex, and dorsolateral prefrontal cortex.

 

The amygdala is interconnected with decision-making circuits in our brain. This is what causes us to second-guess our gut feelings and not act on them. Your anterior cingulate cortex (ACC) can “detect” a conflict between your gut feeling (“this person is different from me”) and your conscious views (“never judge a book by its cover”). This triggers another area of our brain, the dorsolateral frontal cortex (DLPFC) to activate. The DLPFC can control the amygdala’s activation. So, it’s sort of that voice in your head that calms you down and says, “Give him a chance” when your date’s first impression doesn’t exactly go well.

 

My Now

Together, my amygdala has been a bit afraid of all these new people and social rules I don’t know. My anterior cingulate cortex reminds me this is an adventure I want to be in, alleviating my tension between my fear and excitement of the unknown. And my dorsolateral prefrontal cortex reminds me that no matter how unfamiliar a place might seem, I will always find my unfamiliar familiarity and piece of home anywhere I go.

Wherever you go, let people surprise you. You’ll find your own unfamiliar familiarity anywhere you go.

I’d like to leave you with the words I got from a visiting professor at Emory. It’s become my motto and gets me through homesickness: “We are scientists. The more lost we think we are, the more at home we actually are.” 

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Posted on June 17, 2017 by in Neuroscience

Beauty in the Brain of the Beholder

Posted on June 11, 2017 by | 7 comments

 

“Cirque” by Georges Seurat, and example of pointillism in a dynamic painting

When I first began studying French in middle school, I was immediately drawn to the vast amount of famous artwork that was so highly valued in French culture. I vividly remember being mesmerized by the works of Vincent Van Gogh, Claude Monet, and particularly Georges Seurat, who pioneered neo-impressionism with the use of pointillism in his masterpieces. At the time, my 13 year-old self couldn’t even begin to understand how the use of such distinct painting styles could illicit different responses from the viewer’s perspective. Seven years later, while studying neuroscience in Paris, I finally decided to delve into how our brain perceives different types of art.

Picture acquired from: http://commons.wikimedia.org/wiki/File:Musée_d'Orsay.jpg

The Musee D’Orsay in Paris, France

The Musee d’Orsay, located along the Seine River in Paris, France

After a visit to the Musée d’Orsay and seeing famous artwork firsthand, I began doing some research into the different neurological processes and brain areas involved in art perception. Several studies have explored different models and explanations for variations in individual preferences for art. One study investigates the role of ventral pathways in the visual system in object and shape perception, and how the signals our retina receives can form distinct representations of objects based off of contour, structure, shape tuning, and object memory (Connor et al., 2007). Another examines the correlation between the appreciation for visually complex images and level of visual-object working memory (Sherman et al., 2015).

Unsurprisingly, many studies delve into how movement perception influences aesthetics, but most of this research refers to artwork portraying human subjects. This struck me as odd, especially considering how so many famous works of Van Gogh and Monet depict nature in a way that seems dynamic. This prompted me to do a little digging into how we appreciate and perceive movement in art containing natural scenes without human subjects. My tendency to geek out over anything brain-related made me even more interested in which brain areas processed this information, and whether different cortical areas are involved in processing movement in human subjects versus nature scenes.

“La Nuit etoilee” by Vincent Van Gogh, an example of a dynamic nature scene

One 2015 study published in the Frontiers of Human Neuroscience attempts to answer this question by using brain imaging technology to identify where exactly we process static versus dynamic artwork depicting either humans or nature (Di et al., 2015). Researchers predicted that motor mirror mechanisms would be involved in assessing movement of human subjects, and primary visual areas along with deep temporal areas (associated with processing sensory input for visual memory) to be involved in assessing movement of nature scenes. They also hypothesized that activity in the posterior parietal cortex, associated with spatial and motor processing, would be higher in evaluating dynamic images compared to static images.

“Le Bassin aux nympheas harmoine rose” by Claude Monet, another example of a dynamic nature scene

In the study, 19 undergraduate students with no prior formal knowledge of art volunteered to participate in three tasks of observation, aesthetic judgement, and movement judgement (on a numeric scale) in response to human dynamic, human static, nature dynamic, and nature static artwork. Subjects responded to 24 images, 6 for each category. They viewed the images while inside an fMRI scanner so brain activity could be recorded and visualized as they completed the 3 tasks for each painting. Observation tasks formed the basis for aesthetic judgement, which always preceded movement judgement to avoid any influence movement perception might have on the aesthetic experience.

“Paysage decoratif” by Lawren Stewart Harris, an example of a static nature scene

Results from the observation tasks showed that nature stimuli resulted in enhanced activation in occipital and posterior parietal areas, while human stimuli resulted in activation in the inferior and middle temporal sulci, or areas that have been connected to facial recognition (though their exact functions remain unknown). Results from the aesthetic judgement task fell in line with the previous results, with the same areas being activated for human and nature stimuli. However, aesthetic judgement of nature stimuli also resulted in activation of the right central insula, involved in higher-level processes and functions. Temporal activation was higher in dynamic versus static human subjects, while posterior and central insula activity was higher in static versus dynamic scenes of nature. Results from the movement judgement task also fell in line with those of the previous two tasks. Additionally, results indicated that activation in the posterior parietal and intraparietal sulcus and left inferior middle temporal sulcus in response to dynamic versus static images, however these observations were only significant in artwork containing human subjects (Di et al., 2015).

Activation during Aesthetic Judgement; Figure 5, (Di et al., 2015)

“Repetition d’un ballet sur la scene” by Edgar Degas, an example of a dynamic human painting

Many of the cortical areas activated in the three tasks are mainly involved in the “perceptual analysis, implicit memory integration and explicit classification” of stimuli (Di et al., 2015). While the results of the study thoroughly identify and analyze the underlying similarities in activation of different cortical areas involved in aesthetic and movement judgment, it does not account for other factors that have a large influence on art perception, such as personality or past experiences. Reverse experiments testing the effects of loss of function in brain areas involved in perception could also further our understanding of the specific functions of those cortical areas. Ultimately, this study was more illuminating than I expected in terms of where the brain processes and perceives human and natural art, and definitely satisfied my need to understand what previously confounded me as a child.

References:

Connor, C. E., Brincat, S. L., & Pasupathy, A. (2007). Transformation of shape information in the ventral pathway. Current opinion in neurobiology, 17(2), 140-147.

Di Dio, C., Ardizzi, M., Massaro, D., Di Cesare, G., Gilli, G., Marchetti, A., & Gallese, V. (2015). Human, nature, dynamism: the effects of content and movement perception on brain activations during the aesthetic judgment of representational paintings. Frontiers in human neuroscience, 9.

Sherman, A., Grabowecky, M., & Suzuki, S. (2015). In the working memory of the beholder: Art appreciation is enhanced when visual complexity is compatible with working memory. Journal of Experimental Psychology: Human Perception and Performance, 41(4), 898.

All images of artwork were taken at the Musée d’Orsay on June 11, 2017.

 

 

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Posted in Neuroscience

The Baby Schema Scheme

Posted on June 11, 2017 by | 5 comments

Coming off the Metro on my first day in Paris, one of the most immediate sights was that of a woman and her two children sitting on the ground and holding a sign that read, “famille Syrienne”. Throughout the rest of the week, I saw countless homeless people and families, many with children under the age of three. Not only did the homeless often have children, but a large amount also had one or two dogs. While walking to class one day, I even saw a man with a puppy that couldn’t be over two months old. This sparked a question in me- does the appearance of a baby or puppy increase the chance of charitable giving from others?

Figure 1: Homeless Syrian woman with her baby

I believe most people would think the answer to that question is obvious; if given the option to donate to homeless person with a baby or a homeless person without, the logical decision, in terms of effectiveness of the donation, would lean towards the family. However, if we put aside logic-based decision making and focus on spur-of-the-moment choices, would having a baby or puppy make a difference?

Before I did research on experiments from the past, I conducted my own small observational study. At the Bastille Métro Station (Figure 2), I observed the number of people who gave money to both a woman with a baby (Figure 1) and a woman without for five minutes each. Out of 63 people who passed adjacent to the woman with a baby, 4 gave her change, for a percentage of 6.35%. Out of 56 people who passed adjacent to the woman without a baby, only 1 person gave change, for a percentage of 1.79%. Although this observation cannot be statistically analyzed to imply much, as it was a very short study with very few variables controlled, it seems as though the presence of the baby had helped to increase the chance of a donation.

Figure 2: Location of Bastille Station in Paris

In order to find out more information on the neurobiological processes involved in this difference, I read through a study performed by Glocker et al. (2009) on how the “baby schema” modulates the reward system in nulliparous women (women who have never given birth). The baby schema is the physical features of babies, such as a round face and big eyes, that motivates caretaking behavior and attracts attention. This short article modified different aspects of baby schema and observed the levels of activation in associated brain regions in 16 women in their twenties. Glocker et al. hypothesized that an increase in the baby schema “cuteness rating” would cause an increase in blood oxygenation level-dependent (BOLD) fMRI brain activity in the mesocorticolimbic system, which is comprised of the dopaminergic midbrain, nucleus accumbens, amygdala, and ventromedial prefrontal cortex.

Figure 3: Examples of high, unmanipulated, and low baby schema faces used in the study by Glocker et al.

Using adjusted images of infant faces, such as in Figure 3, they found a linear increase in activation due to baby schema in the left anterior cingulate cortex, left precuneus, left fusiform gyrus, and right nucleus accumbens (Figure 4). The researchers then went on to discuss their findings in relation to the functional properties of these regions, specifically the nucleus accumbens, precuneus, and fusiform gyrus.

Figure 4: (A) Results of fMRI BOLD testing by Glocker et al. Areas of interest include left anterior cingulate cortex (ACC), left precuneus (PCu), left fusiform gyrus (FG), and right nucleus accumbens (NAcc). (B) Increases in BOLD percent signal change due to increased baby schema.

They described the nucleus accumbens as being linked to reward-based behavior, and that its activation could release approach behavior towards infants. In addition, the nucleus accumbens is a part of the striatum, which has been associated with processes such as mutual cooperation, charitable donation, and social bonding. The activation of this region due to seeing a baby’s face could influence women into donating money. Another brain region of interest was that of the precuneus, which is commonly associated with attention, suggesting that baby schema brings and holds attention to an infant’s face. Finally, the fusiform gyrus plays a large role in facial perception, and may encode baby schema features to send along to the nucleus accumbens to appoint motivational value.

Overall, the study does a good job in identifying the regions of brain that are sensitive to baby schema. However, it was limited to women in their twenties who have never given birth. This category of people is only a small percentage of those who encounter homelessness, so it doesn’t fully answer my question. Despite its limited conclusions, Glocker et al. discusses how other studies have shown that, while women most likely are more responsive to the baby schema than men, they both process it similarly.

Although this article was informative on the effects of the human baby schema, I was interested in the subject of puppies as well. So, I read an article titled “Sweet Puppies and Cute Babies: Perceptual Adaptation to Babyfacedness Transfers across Species” by Golle et al. The researchers used a perceptual adaptation paradigm to test whether the evaluation of cuteness is species-specific or exists across multiple species. Their first experiment involved subjects rating 78 babies’ faces on a scale of 1-6. The 5 least cute and cutest babies were used as “adaptor” stimuli. All remaining faces were individually paired (one cute and one less cute) and morphed together. The subjects were then tested in three respective parts: rating the morphed faces in cuteness, looking at the adaptor faces carefully, and then rating the morphed faces again. In general, the subjects rated the babies as cuter during the second round of rating, after the adaptation phase. From this, it can be reasoned that the brain grows accustomed to a range of cuteness. During a second experiment, the researchers tested if a similar adaptation can occur when shown faces of dogs.

Figure 5: A homeless man with two dogs in Paris

Using the same procedure, but swapping the human infant adaptor stimuli with cute and less cute puppy faces, Golle et al. found that the adaptation of puppy faces similarly influenced the perception of baby faces to have an increased cuteness value during the second round of rating. From this data, the researchers concluded that facial cuteness adaptation transfers across species and induces the same “cuteness decoding” process (a.k.a. the effects of the baby schema found in the first study). They gather that human beings have a general instinct to take care of newborns of the same or different species- a desire that stems from the cuteness of the baby.

Figure 6: My dog, Buddy. What cuteness rating would you give him?

From these two studies, it can be concluded that both babies and puppies’ cuteness causes an activation in certain areas of the brain associated with caretaking, attention, and charitable giving. This in turn can lead to an increased influx of donations towards homeless with young children or dogs compared to those without. So, next time you give money to a homeless family, what might seem to be a simple altruistic decision might actually be a series of complicated facial analysis!

References:

Glocker ML, Langleben DD, Ruparel K, Loughead JW, Valdez JN, Griffin MD, Sachser N, Gur RC (2009) Baby schema modulates the brain reward system in nulliparous women. Proceedings of the National Academy of Sciences of the United States of America. 106(22):9115-9119.

Golle J, Lisibach S, Mast FW, Lobmaier JS (2013) Sweet puppies and cute babies: perceptual adaptation to babyfacedness transfers across spepcies. PLoS ONE 8(3):e58248

Figures 1 and 6 were taken by me

Figures 2 and 5 were obtained from a search in Creative Commons:

Figure2: https://upload.wikimedia.org/wikipedia/commons/thumb/7/74/Paris_department_land_cover_location_map.svg/2000px-Paris_department_land_cover_location_map.svg.png

Figure5: https://upload.wikimedia.org/wikipedia/commons/a/a6/Homeless_puppies%2C_Paris%2C_October_2008.jpg

Figures 3 and 4 were taken from the study by Glocker et al.

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There’s Nothing Like the Smell of Home

Posted on June 11, 2017 by | 10 comments

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.

Cheers,

Sarah

Bibliography:

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 Reviews, 26(3), 321-352.

Fortin, N. J., Wright, S. P., & Eichenbaum, H. (2004). Recollection-like memory retrieval in rats is dependent on the hippocampus. Nature, 431(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 neuroscience, 8, 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.

Images:

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

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La belle ville de Paris: Perceptions of Beauty

Posted on June 11, 2017 by | 3 comments

So far, two weeks of getting lost in the metro, enduring drastic weather changes, and having frustrating French conversations at the market have passed during our stay in Paris. From the expectation of having exact change for every monetary transaction to the snarling gazes at our (somewhat) loud group of fifteen in the metro, adapting to the social norms of the French culture has proven to be quite the challenge (I’m just glad I haven’t been pickpocketed…yet).

Arc de Triomphe

However, living in one of the world’s most beautiful cities and being surrounded by some of the most famous landmarks in the world have made it easy to forget these daunting hardships faced by our curious group of American college students. Whether it’s marveling at the size of the Eiffel Tower, walking down the Champs-Élysées with the Arc de Triomphe always in view, or even just observing the characteristically quaint Parisian architecture of all the apartment buildings, Paris always has something to offer around every corner. Thus, as a student who’s on this trip to learn more about neuroscience (and to eat lots of delicious food), I began to question myself: What makes these Parisian scenes so appealing and beautiful? What’s the neuroscience behind what we determine as beautiful? I’m hungry, where can I find me some crêpes?

Eiffel Tower

I came across a study focusing on brain systems with regards to aesthetic and perceptual judgment. The scientists who conducted this study, Ishizu and Zeki (2013), have previously shown that the experience of beauty, regardless of its source (for instance, looking at a famous art masterpiece or listening to beautifully composed music), activates an area of the medial orbitofrontal cortex (mOFC) (Ishizu and Zeki, 2011). This area of our brain is involved in the cognitive process of decision-making. Thus, judgment comes into play when you’re making these decisions.

medial orbitofrontal cortex (mOFC)

If you were shown a picture and you were told to say whether you thought it was beautiful or not, not only are you making judgements based on the picture’s aesthetics, you’re also making judgements based on its quality. So what’s the difference between the two? Let’s say you were given two paintings and you were told to determine which one you thought was more beautiful. When shown these pictures, you see that one painting (let’s say painting A) was three times the size of painting B and also seemed to appear brighter. Right off the bat, you’ve made judgements about painting A’s qualities (size and brightness). However, when you observe painting B, you notice that even though it may not be as big or as bright as painting A, you find painting B’s content to be portrayed as more aesthetically pleasing than painting A. This study aimed to figure out whether aesthetic judgements also involved the activity of the mOFC and how these two types of judgement contribute towards judging the beauty of something, like crêpes!

To test this, human volunteers (non-artists or musicians to alleviate any bias) went through two sessions: aesthetic and brightness. In each of these session, the subjects were shown a series of two paintings and were told to judge which one was more beautiful (in the aesthetic session) or brighter (in the brightness session). The researchers used functional magnetic resonance imaging, or fMRI, scans that acquired readings of blood oxygen levels in the brain. This allows researchers to see what areas of the brain are being activated when the subjects are told to judge the paintings.

Figure 6 of Ishuzu and Zeki (2013) – shows what brain areas are affected by the type of judgment (brightness or aesthetic).

Results showed that aesthetic and brightness judgments use both shared and separate brain systems. While aesthetic judgement mainly activated subcortical regions and the OFC (areas previously mentioned that were associated with beauty), brightness judgement did not activate any areas with significance compared to the areas activated by aesthetic judgment. However, both aesthetic and brightness judgement activated shared systems, mainly involving the dorsolateral prefrontal cortex (dlPFC) (involved with decision making, memory, and cognition) and bilateral anterior insula (known to be involved with many functions, including cognitive and emotional processes).

A beautiful crêpe

This new insight has led me to think about how I judge Paris’s beauty. Do I think the Eiffel Tower is beautiful, or am I just awestruck by its massive size? Do I think the Parisian architecture is beautiful, or is my familiarity to what I normally see in America causing me to think otherwise? The study mentions that further separating the processes of judgement, decision, and experience is difficult because they all use the same brain areas. Being able to understand these separate processes would allow us to really understand how this part of our brain works and finally uncover the truth as to why I find crêpes so beautiful.

____________________________________________________________________

Sources:

Ishizu T, Zeki S (2011) Toward A Brain-Based Theory of Beauty. PLoS ONE 6(7):e21852.

Ishizu T, Zeki S (2013) The brain’s specialized systems for aesthetic and perceptual judgment. The European Journal of Neuroscience 37(9):1413–1420.

mOFC picture: https://commons.wikimedia.org/wiki/File:MRI_of_orbitofrontal_cortex.jpg

Arc de Triomphe, Eiffel Tower, and Crêpe pictures were personally taken.

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La Rage dans les Rues

Posted on June 11, 2017 by | 3 comments

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

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Chill, it’s just coffee!

Posted on June 22, 2015 by | 2 comments

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

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).

antimicrobe.org
(antimicrobe.org)

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!)

(www.pt.kumc.edu:research:diabetes-research-lab:RatTreat01)
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,

Alex

 

References

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

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Making Chocolate like a Pro

Posted on June 22, 2015 by | 4 comments

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

References:

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.

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