Tag Archives: bilingual

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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Why put so much effort into learning a second language?

Posted on June 22, 2015 by | 6 comments

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

~ Amy Yeh

References

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

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

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

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

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“Hello” or “Bonjour” ?

Posted on June 7, 2015 by | 3 comments

Hello world,

This past week has been extremely interesting, yet exciting, to say the least. After a TERRIBLE delay at JFK airport, I finally made it to Paris (about 6 hours behind schedule…). Once settled into my room, I met up with my friend, Sasha, to grab a quick dinner. We decided to go to a small restaurant close to where we live, as our long day of traveling left us extremely tired. When we sat down at the restaurant, the waiter walked over and said, “Bonjour, comment puis-je vous aider?” This caught me extremely off guard, as this was the first time I engaged in a conversation with a true francophone.

IMG_1115

Sasha (left) and me (right) at dinner

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Sasha and me at the Eiffel Tower

 

Let me rewind a little bit. I have studied French since 6th grade, and although it may not be my primary concentration in college, it plays a huge role in my academic career. However, this was my first time in a French speaking country, so I have not had much experience with French conversation, aside from with my fellow French-speaking peers and professors. So, when the waiter confronted me and asked a question in French, I was rightfully so caught off guard.

 

 

(Anyway, returning to the restaurant…) Sasha, being from Montreal and growing up speaking French with her family, swiftly answered the waiter. After a few seconds of gathering myself and adjusting my vocabulary, I too answered him (in French, of course). This event made wonder what physiological differences, if any, occurred in my brain when switching between English and French vocabulary. Were different areas of my brain active for French words versus English words and vice versa? This question sparked my interest, so, upon returning to my room I searched for an answer.

Before I try and explain the studies I found, let me give you a quick and easy lesson concerning neuroscience and language. Broca’s area, a region of the frontal part of the brain, is linked to the production of speech, while Wernicke’s area, a region of the temporal part of the brain (slightly above where your ears are), is linked to the comprehension aspects of speech. In order to engage in a coherent conversation with another individual, one must use both of these areas, as the language one hears must be understood
(via Wetumblr_memuxuR4xw1qf721rrnicke’s area) and the language one speaks must be intelligible (via Broca’s area). So, when looking for an answer to my original question about language, I immediately thought that this must be the sole system affected, but boy was I wrong.

 

After some quick searching, I stumbled upon an article by Correia et al., 2014, concerning brain activation in bilingual individuals. The researchers in this study subjected bilingual participants, fluent in English and Dutch, to a series of experimentations in which the participants were placed inside an fMRI and told to listen to a series of words. The words consisted of the names of specific animal species, and the language spoken varied between English and Dutch. The fMRI constructed images of the participant’s brains, highlighting the regions most active during this process. By examining and comparing the fMRI images created by solely Dutch words, solely English words, and a combination of the two, Correia et al. isolated several regions of the brain active for both languages. The main region of activity they observed was the anterior temporal lobe (ATL). This cortical region is associated with semantic memory, that is, memory of physical objects, people, information, and (most important to this study) words (Bonner and Price, 2013). This finding is significant as it provides evidence that semantic knowledge is processed in a language-independent form in the brains of bilingual listeners (Correia et al., 2014). Essentially, this means that as the participants listened the either English or Dutch words, their ATLs become equivalently active for each. So, when I was in the restaurant with Sasha, although I may have been caught off guard by the waiter speaking French, similar regions of my brain became active compared to if the waiter spoke English to me.

Screen Shot 2015-06-07 at 12.05.16 PM

A figure from Correia et al. (2014) depicting the language-independent regions of the brain, one of which being the anterior temporal lobe (ATL)

Another interesting study I found was conducted by Mohades et al. in 2012. In this study, the researchers assessed the brain circuitry associated with language in children aged 8-11 years old. They compared this circuitry in children raised monolingual to those raised bilingual. Through this, the researchers discovered significantly different white matter density in specific brain regions involved with spoken language and comprehension of language. Certain areas of bilingual’s brains contained different densities of white matter in comparison to the brain’s of monolinguals (Mohades et al., 2012). This means that the circuitry of the brain involved with language differs depending on one’s language capabilities. So, in relation to my brain and Sasha’s brain, we have different densities of white matter in specific regions of our brains, since Sasha was raised bilingual (woah).

3DSlicer-KubickiJPR2007-fig6

The type of fMRI imaging used by Mohades et al. (2011) to measure white matter integrity (density).

 

I found both of these articles very interesting because they offer different findings regarding brain activation in bilinguals. In my NBB classes I learn about many regions of the brain discussed in these studies, yet I never knew the role they played in bilingual individuals. With this newfound knowledge, I am interested in doing further research to discover more differences in brain activation associated with language.

~ Ethan Siegel

References

Bonner M, Price A (2013) Where is the anterior temporal lobe and what does it do? The Journal of Neuroscience. 33(10): 4213-4215

Correia J, Formisano E, Valente G, Hausfeld L, Jansma B, Bonte M (2014) Brain-based translation: fMRI decoding of spoken words in bilinguals reveals language-independent semantic representations in anterior temporal lobe. The Journal of Neuroscience. 34(1):332–338

Mohades S, Struys E, Van Schuerbeek P, Mondt K, Van de Craen P, Luypaert R (2011) DTI reveals structural differences in white matter tracts between bilingual and monolingual children. SciVerse ScienceDirect. 1435: 72-80

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How Can You Tell I’m American?

Posted on June 19, 2013 by | 7 comments

One of the greatest challenges about being in Paris is being constantly exposed to a foreign language. I have found that fewer Parisians than expected speak English. Having studied French for a number of years, I am always eager to test my ability to communicate with native French speakers. I try to practice French in Paris as often as possible, whether it is through ordering food (obviously my most important application of the language), asking for directions, or even giving directions sometimes. Just a couple of days ago I asked a young lady for directions while on the metro and even though I knew that I had appropriately phrased my sentence in French, she responded in English. I knew that my accent had given away the fact that my native language is English, but I had expected her to respond in French. I have found myself in similar situations on many occasions. One time I was speaking French to an angry Cite Universitaire, the campus on which we are living, security guard after I had been locked out of my room and he responded in English, “I don’t speak English.” I was puzzled and in French let him know that I can speak French and he responded, “no you can’t.” I chose not to take this second encounter personally and instead began to wonder what about my speaking bothered him so much. It must have been my accent. Accent perception is such an interesting concept. We can tell what country a person is from, or even perhaps the city in which they were born not by listening to the words that they say, but by listening to the way that they say them.

Cite Universitaire (labeled as A)- where we have been living for the past 3 weeks.

In a study done by Adank et al. (2011), native monolingual Dutch speakers were played Dutch phrases in a Dutch accent and were also played the same Dutch phrases in an unfamiliar accent. While listening, the subjects’ brains were monitored using an fMRI scanner, a machine which uses magnetic imagining to monitor brain activity. The study showed that when the sound stimuli changed from the familiar to the unfamiliar accent, more of the subjects’ superior temporal gyrus (STG), a brain area involved in basic auditory language processing, became activated. The STG has also been shown to be associated with phonetic-analytic listening to speech. Perhaps this gives insight into as to why more of the STG is activated when listening to an unfamiliar accent; the brain is recruiting more cells to help analyze the phonetics of the speech because the speech is foreign. It is important to understand this because when French individuals hear me speaking French with an English accent, their STG becomes increasingly activated and they recognize that not only am I speaking in an accent, but then, through using other areas of the brain, may be able to understand what language I am speaking.

An exhibit in the Louvre Museum spelling out "love differences" in many different languages.

Whenever I’m on the metro and everyone around me is speaking French, it is difficult for me to decipher what they are saying unless they are speaking directly to me. I was curious as to the ways in which my brain would have responded to the sounds on the metro had I learned French at a younger age, but second to English. I wondered how the bilingual brain responds to language perception in general. In a study done by Archila-Suerte et al. (2012), a group of bilingual Spanish-English speaking children (whose native language is Spanish) and monolingual English speaking children were played the English syllables, “saf,” “sof,” and “suf,” while watching a silent film. These syllables were chosen because they are pronounced similarly in Spanish and would provide more insight into activation of the bilingual brain (perhaps because they may activate regions involved in perception of both languages). The subjects were told to focus on the silent film while the syllables were being played to them and simultaneously the group was analyzing the subjects’ brains using an fMRI scanner. The study was performed for young and older bilingual and monolingual children. The group found that the young monolingual and bilingual children had the STG activated (let’s call this area 1) while listening to the syllables. This data implies that the bilingual children when just beginning to learn the second language perhaps relates it to the first language and processes it in the same brain area. However, the older monolingual children still only had area 1 activated during the task whereas bilingual children had area 1 as well as other areas in the brain activated. This suggests that as bilingual children begin to master a second language more, their brain recruits other areas, other than area 1, to help distinguish between the two languages. Perhaps my brain is similar to the brain of the younger bilingual children, since I have not yet begun to master the French language. My brain may not be able to recruit other areas to help area 1 decipher a language other than English and this may be why I am unable to easily pick out French words and conversations while on the train. However, French individuals who are able to easily recognize my accent, process what my native language is, and then respond in my native language perhaps have activation of other brain areas which help the STG decipher the language. This is due to the idea that they are bilingual and no longer need to relate their second mastered language to their native language. It would be interesting to see what the combined results of the first and second study would be; to pursue a study that looked at monolingual and bilingual individuals’ brain activation to speaking their common language in an accent. I am curious to see if by being well versed in more than one language, bilingual children are able to recognize accents easier. Maybe one day I’ll master the French language enough to not have to constantly compare it to English! I guess I’ll just have to ensure that this isn’t my last trip to Paris…

–          Ankita Gumaste

Adank P, Noordzij ML, Hagoort P (2011) The role of planum temporal in processing accent variation in spoken language comprehension. Human brain mapping 33: 360-372.

Archila-Suerte P, Zevin J, Ramos AI, Hernandez AE (2012) The neural bases of non-native speech perception in bilingual children. NeuroImage 67: 51-63.

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