Learning another language
About these topic collections
I’ve been reporting on memory research for over ten years and these topic pages are simply collections of all the news items I have made on a particular topic. They do not pretend to be in any way exhaustive! I cover far too many areas within memory to come anywhere approaching that. What I aim to do is provide breadth, rather than depth. Outside my own area of cognitive psychology, it is difficult to know how much weight to give to any study (I urge you to read my blog post on what constitutes scientific evidence). That (among other reasons) is why my approach in my news reporting is based predominantly on replication and consistency. It's about the aggregate. So here is the aggregate of those reports I have at one point considered of sufficient interest to discuss. If you know of any research you would like to add to the collection, feel free to write about it in a comment (please provide a reference).
An Indian study involving 648 dementia patients, of whom 391 were bilingual, has found that, overall, bilingual patients developed dementia 4.5 years later than the monolingual ones. There was no additional advantage to speaking more than two languages.
The effect remained after factors such as education, sex, occupation, and urban vs. rural dwelling, had been accounted for. The finding is consistent with previous research, and is not only the largest study so far on the subject, but the first to show the effect also applies to illiterate people who had not attended school. Moreover, the effect was found in three different types of dementia: frontotemporal, vascular, and Alzheimer’s disease.
 Bilingualism delays age at onset of dementia, independent of education and immigration status. Neurology. 81(22), 1938 - 1944.(2013).
In my last report, I discussed a finding that intensive foreign language learning ‘grew’ the size of certain brain regions. This growth reflects gray matter increase. Another recent study looks at a different aspect: white matter.
In the study, monthly brain scans were taken of 27 college students, of whom 11 were taking an intensive nine-month Chinese language course. These brain scans were specifically aimed at tracking white matter changes in the students’ brains.
Significant changes were indeed observed in the brains of the language learners. To the researchers’ surprise, however, the biggest changes were observed in an area not previously considered part of the language network: the white matter tracts that cross the corpus callosum, the main bridge between the hemispheres. (I’m not quite sure why they were surprised, since a previous study had found that bilinguals showed higher white matter integrity in the corpus callosum.)
Significant changes were also observed within the left-hemisphere language network and in the right temporal lobe. The rate of increase in white matter was linear, showing a steady progression with each passing month.
The researchers suggest that plasticity in the adult brain may differ from that seen in children’s brains. While children’s brains change mainly through the pruning of unwanted connections and the death of unwanted cells, adult brains may rely mainly on neurogenesis and myelinogenesis.
The growth of new myelin is a process that is still largely mysterious, but it’s suggested that activity at the axons (the extensions of neurons that carry the electrical signals) might trigger increases in the size, density, or number of oligodendrocytes (the cells responsible for the myelin sheaths). This process is thought to be mediated by astrocytes, and in recent years we have begun to realize that astrocytes, long regarded as mere ‘support cells’, are in fact quite important for learning and memory. Just how important is something researchers are still working on.
The finding of changes between the frontal hemispheres and caudate nuclei is consistent with a previously-expressed idea that language learning requires the development of a network to control switching between languages.
Does the development of such a network enhance the task-switching facility in working memory? Previous research has found that bilinguals tend to have better executive control than monolinguals, and it has been suggested that the experience of managing two (or more) languages reorganizes certain brain networks, creating a more effective basis for executive control.
As in the previous study, the language studied was very different from the students’ native language, and they had no previous experience of it. The level of intensity was of course much less.
I do wonder if the fact that the language being studied was Mandarin Chinese limits the generality of these findings. Because of the pictorial nature of the written language, Chinese has been shown to involve a wider network of regions than European languages.
Nevertheless, the findings add to the evidence that adult brains retain the capacity to reorganize themselves, and add to growing evidence that we should be paying more attention to white matter changes.
 White Matter Structure Changes as Adults Learn a Second Language. Journal of Cognitive Neuroscience. 24(8), 1664 - 1670.(2012).
Bialystok, E., Craik, F. I. M., & Luk, G. (2012). Bilingualism: consequences for mind and brain. Trends in Cognitive Sciences, 16(4), 240–250. doi:10.1016/j.tics.2012.03.001
A small Swedish brain imaging study adds to the evidence for the cognitive benefits of learning a new language by investigating the brain changes in students undergoing a highly intensive language course.
The study involved an unusual group: conscripts in the Swedish Armed Forces Interpreter Academy. These young people, selected for their talent for languages, undergo an intensive course to allow them to learn a completely novel language (Egyptian Arabic, Russian or Dari) fluently within ten months. This requires them to acquire new vocabulary at a rate of 300-500 words every week.
Brain scans were taken of 14 right-handed volunteers from this group (6 women; 8 men), and 17 controls that were matched for age, years of education, intelligence, and emotional stability. The controls were medical and cognitive science students. The scans were taken before the start of the course/semester, and three months later.
The brain scans revealed that the language students showed significantly greater changes in several specific regions. These regions included three areas in the left hemisphere: the dorsal middle frontal gyrus, the inferior frontal gyrus, and the superior temporal gyrus. These regions all grew significantly. There was also some, more selective and smaller, growth in the middle frontal gyrus and inferior frontal gyrus in the right hemisphere. The hippocampus also grew significantly more for the interpreters compared to the controls, and this effect was greater in the right hippocampus.
Among the interpreters, language proficiency was related to increases in the right hippocampus and left superior temporal gyrus. Increases in the left middle frontal gyrus were related to teacher ratings of effort — those who put in the greatest effort (regardless of result) showed the greatest increase in this area.
In other words, both learning, and the effort put into learning, had different effects on brain development.
The main point, however, is that language learning in particular is having this effect. Bear in mind that the medical and cognitive science students are also presumably putting in similar levels of effort into their studies, and yet no such significant brain growth was observed.
Of course, there is no denying that the level of intensity with which the interpreters are acquiring a new language is extremely unusual, and it cannot be ruled out that it is this intensity, rather than the particular subject matter, that is crucial for this brain growth.
Neither can it be ruled out that the differences between the groups are rooted in the individuals selected for the interpreter group. The young people chosen for the intensive training at the interpreter academy were chosen on the basis of their talent for languages. Although brain scans showed no differences between the groups at baseline, we cannot rule out the possibility that such intensive training only benefited them because they possessed this potential for growth.
A final caveat is that the soldiers all underwent basic military training before beginning the course — three months of intense physical exercise. Physical exercise is, of course, usually very beneficial for the brain.
Nevertheless, we must give due weight to the fact that the brain scans of the two groups were comparable at baseline, and the changes discussed occurred specifically during this three-month learning period. Moreover, there is growing evidence that learning a new language is indeed ‘special’, if only because it involves such a complex network of processes and brain regions.
Given that people vary in their ‘talent’ for foreign language learning, and that learning a new language does tend to become harder as we get older, it is worth noting the link between growth of the hippocampus and superior temporal gyrus and language proficiency. The STG is involved in acoustic-phonetic processes, while the hippocampus is presumably vital for the encoding of new words into long-term memory.
Interestingly, previous research with children has suggested that the ability to learn new words is greatly affected by working memory span — specifically, by how much information they can hold in that part of working memory called phonological short-term memory. While this is less important for adults learning another language, it remains important for one particular category of new words: words that have no ready association to known words. Given the languages being studied by these Swedish interpreters, it seems likely that much if not all of their new vocabulary would fall into this category.
I wonder if the link with STG is more significant in this study, because the languages are so different from the students’ native language? I also wonder if, and to what extent, you might be able to improve your phonological short-term memory with this sort of intensive practice.
In this regard, it’s worth noting that a previous study found that language proficiency correlated with growth in the left inferior frontal gyrus in a group of English-speaking exchange students learning German in Switzerland. Is this difference because the training was less intensive? because the students had prior knowledge of German? because German and English are closely related in vocabulary? (I’m picking the last.)
The researchers point out that hippocampal plasticity might also be a critical factor in determining an individual’s facility for learning a new language. Such plasticity does, of course, tend to erode with age — but this can be largely counteracted if you keep your hippocampus limber (as it were).
All these are interesting speculations, but the main point is clear: the findings add to the growing evidence that bilingualism and foreign language learning have particular benefits for the brain, and for protecting against cognitive decline.
 Growth of language-related brain areas after foreign language learning. NeuroImage. 63(1), 240 - 244.(2012).
Growing evidence points to greater education and mentally stimulating occupations and activities providing a cognitive reserve that enables people with developing Alzheimer's to function normally for longer. Cognitive reserve means that your brain can take more damage before it has noticeable effects. A 2006 review found that some 30% of older adults found to have Alzheimer’s when autopsied had shown no signs of it when alive.
There are two relevant concepts behind the protection some brains have: cognitive reserve (which I have mentioned on a number of occasions), and brain reserve, which is more structural. ‘Brain reserve’ encapsulates the idea that certain characteristics, such as a greater brain size, help protect the brain from damage. Longitudinal studies have provided evidence, for example, that a larger head size in childhood helps reduce the risk of developing Alzheimer’s.
While cognitive reserve has been most often associated with education, it has also been associated with occupation, bilingualism, and music. A new study provides physical evidence for how effective bilingualism is.
The Toronto study involved 40 patients with a diagnosis of probable Alzheimer’s, of whom half were bilingual (fluent in a second language, and consistent users of both languages throughout their lives). Bilingual and monolingual patients were matched on a test of cognitive function (the Behavioral Neurology Assessment). The two groups were similar in education levels, gender, and performance on the MMSE and the clock drawing test. The groups did differ significantly in occupational status, with the monolinguals having higher job status than the bilinguals.
Notwithstanding this similarity in cognitive performance, brain scans revealed that the bilingual group had substantially greater atrophy in the medial temporal lobe and the temporal lobe. The two groups did not differ in measures of central and frontal atrophy, however — these regions are not associated with Alzheimer’s.
In other words, bilingualism seems to specifically help protect those areas implicated in Alzheimers, and the bilinguals could take much greater damage to the brain before it impacted their cognitive performance. It is suggested that the act of constantly switching between languages, or suppressing one language in favor of other, may help train the brain to be more flexible when the need comes to compensate for damaged areas.
The findings are consistent with previous observational studies suggesting that bilingualism delays the onset of Alzheimer's symptoms by up to five years.
Valenzuela MJ and Sachdev P. 2006. Brain reserve and dementia: A systematic review. Psychological Medicine, 36(4): 441e454.
Bilingual parents of children with autism spectrum disorder often decide to speak only one language around their child because of advice from child development professionals who believe that exposure to two languages might further limit the child’s communication skills. Two recent studies challenge that assumption.
One study tested the vocabulary size of 14 bilingual (English-Mandarin/Cantonese) and 14 English-monolingual young children with ASD (aged 3-6). Bilingual children had a larger total vocabulary than monolingual children. When translation equivalents (two words in each language with the same meaning) were counted only once, the vocabularies of both bilingual and monolingual children were not significantly different. Both groups had equivalent scores on all but one measure of language and vocabulary, including English production vocabulary, conceptual production vocabulary, and vocabulary comprehension.
The second Canadian study found similar results in a slightly larger group of children (45 bilingual and 30 monolingual children with an average age of around 5). Languages covered were diverse: French, English, Chinese, Farsi, Hebrew, Italian, Romanian, Spanish and Tamil. Bilingual children were divided into those who were exposed to both languages from infancy, and those who were exposed later (the cut-off was 12 months, but in general changes in the language environment occurred much later: on average, children in the former group were bilingually-exposed for the first 25 months; children in the latter group were monolingually-exposed for the first 31 months). Eleven children were trilingual. In order not to introduce sampler bias, non-verbal children were not excluded — seven participants spoke fewer than 10 words, of whom two were nonverbal.
There were no significant differences between the three groups at a language level, although monolingual and bilingual children exposed from infancy consistently scored higher than bilingual children exposed from a later age. Also, children exposed to two or more languages from infancy scored significantly higher than both groups on social interaction, and those exposed later were worst of the three groups. These differences probably reflect various social variables underlying the different language experiences.
The main reason for the belief that autistic children are better not ‘burdened’ with an additional language is because of their language difficulties. These studies are not saying that a child with ASD raised in two languages will be equally fluent with both. In the second study, second language vocabularies were much smaller than their dominant language vocabularies. But that’s not the point. Whether or not there is any general cognitive advantage in bilingualism for this group, as there is for normally-developing children, remains to be determined. But there is a clear message that parents of ASD children can take on board: if your family is bilingual, relax and enjoy interacting with your ASD child in your language of choice.
 Brief Report: An Exploratory Study of Lexical Skills in Bilingual Children with Autism Spectrum Disorder. Journal of Autism and Developmental Disorders.(2011).
 The Impact of Bilingual Environments on Language Development in Children with Autism Spectrum Disorders. Journal of Autism and Developmental Disorders.(2011).
An increasing number of studies have been showing the benefits of bilingualism, both for children and in old age. However, there’s debate over whether the apparent benefits for children are real, or a product of cultural (“Asians work harder!” or more seriously, are taught more behavioral control from an early age) or environmental factors (such as socioeconomic status).
A new study aimed to disentangle these complicating factors, by choosing 56 4-year-olds with college-educated parents, from middle-class neighborhoods, and comparing English-speaking U.S. children, Korean-speaking children in the U.S. and in Korea, and Korean-English bilingual children in the U.S.
The children were tested on a computer-game-like activity designed to assess the alerting, orienting, and executive control components of executive attention (a child version of the Attention Network Test). They were also given a vocabulary test (the Peabody Picture Vocabulary Test-III) in their own language, if monolingual, or in English for the bilinguals.
As expected, given their young age, English monolinguals scored well above bilinguals (learning more than one language slows the acquisition of vocabulary in the short-term). Interestingly, however, while Korean monolinguals in Korea performed at a comparable level to the English monolinguals, Korean monolinguals in the U.S. performed at the level of the bilinguals. In other words, the monolinguals living in a country where their language is a majority language have comparable language skills, and those living in a country in which their primary language is a minority language have similar, and worse, language skills.
That’s interesting, but the primary purpose of the study was to look at executive control. And here the bilingual children shone over the monolinguals. Specifically, the bilingual children were significantly more accurate on the attention test than the monolingual Koreans in the U.S. (whether they spoke Korean or English). Although their performance in terms of accuracy was not significantly different from that of the monolingual children in Korea, these children obtained their high accuracy at the expense of speed. The bilinguals were both accurate and fast, suggesting a different mechanism is at work.
The findings confirm earlier research indicating that bilingualism, independent of culture, helps develop executive attention, and points to how early this advantage begins.
The Korean-only and bilingual children from the United States had first generation native Korean parents. The bilingual children had about 11 months of formal exposure to English through a bilingual daycare program, resulting in them spending roughly 45% of their time using Korean (at home and in the community) and 55% of their time using English (at daycare). The children in Korea belonged to a daycare center that did offer a weekly 15-minute session during which they were exposed to English through educational DVDs, but their understanding of English was minimal. Similarly, the Korean-only children in the U.S. would have had some exposure to English, but it was insufficient to allow them to understand English instructions. The researchers’ informal observation of the Korean daycare center and the ones in the U.S. was that the programs were quite similar, and neither was more enriching.
 Early Childhood Bilingualism Leads to Advances in Executive Attention: Dissociating Culture and Language. Bilingualism: Language and Cognition. 14(03), 412 - 422.(2011).
Clinical records of 211 patients diagnosed with probable Alzheimer's disease have revealed that those who have spoken two or more languages consistently over many years experienced a delay in the onset of their symptoms by as much as five years. It’s thought that lifelong bilingualism may contribute to cognitive reserve in the brain, enabling it to compensate for memory loss, confusion, and difficulties with problem-solving and planning.
Of the 211 patients of the Sam and Ida Ross Memory Clinic at Baycrest, 102 patients were classified as bilingual and 109 as monolingual. Bilingual patients had been diagnosed with Alzheimer's 4.3 years later than the monolingual patients on average, and had reported the onset of symptoms 5.1 years later. The groups were equivalent on measures of cognitive and occupational level, there was no apparent effect of immigration status, and there were no gender differences.
The findings confirm an earlier study from the same researchers, from the clinical records of 184 patients diagnosed with probable Alzheimer's and other forms of dementia.
 Delaying the onset of Alzheimer disease. Neurology. 75(19), 1726 - 1729.(2010).
Older news items (pre-2010) brought over from the old website
Foreign language better understood in your own accent
While most foreign language courses try hard to provide native speakers, a new study shows that adults find it easier when the teacher speaks it in the same accent as the student. 60 participants aged 18-26, of whom 20 were native Hebrew speakers, 20 new adult immigrants to Israel from the Former Soviet Union, and 20 were Israeli Arabic speakers who began learning Hebrew at age 7-8, has found that while accent made no difference to native Hebrew speakers, both the Russian and Arabic speakers needed less phonological information to recognize Hebrew words when they were pronounced in the accent of their native language.
 Listening with an Accent: Speech Perception in a Second Language by Late Bilinguals. Journal of Psycholinguistic Research. 38(5), 447 - 457.(2009).
Literate Arabic speakers have bilingual brains
Research has found that Arabic-speaking students tend to be less proficient in reading than other students are in their native language. Spoken Arabic comes in a variety of dialects and is quite different from the common written Arabic (Modern Standard Arabic - MSA). A new imaging study has now compared brain activity in a priming task among trilinguals fluent in MSA, spoken Arabic and Hebrew. The results revealed that the cognitive process in using MSA was more similar to that employed for Hebrew, and less similar to the cognitive process of using the spoken native language. These results not only help explain why learning to read is more difficult for Arabic speakers, but also suggests that the most effective way of teaching written Arabic is by using techniques usually employed for the instruction of a second language — including exposing children to written Arabic in preschool or kindergarten.
Ibrahim, R. 2009. The cognitive basis of diglossia in Arabic: Evidence from a repetition priming study within and between languages. Journal of Psychology Research and Behavior Management, 2.
Relearning a forgotten language is easier for those under 40
A small study involving 7 native English speakers who had learned either Hindi or Zulu as children when living abroad, but now had no memory of the neglected language, found that the three who were under 40 could relearn certain phonemes that are difficult for native English speakers to recognize, but those over 40, like those who had never been exposed to the language in childhood, could not. The amount of experience of exposure in childhood ranged from 4 to 10 years, and it’s especially notable that the 47-year old individual who had 10 years exposure, having become almost fluent, still could not recover the ability to distinguish these difficult sounds. It should also be noted that where the ability was recovered (and recovered almost to native ability), it took about 15-20 training sessions. The findings point to the value of early foreign language learning.
 Preserved implicit knowledge of a forgotten childhood language. Psychological Science: A Journal of the American Psychological Society / APS. 20(9), 1064 - 1069.(2009).
Exposure to two languages carries far-reaching benefits
A new study provides evidence that bilingual speakers find it easier to learn a new language than those who only know one language. The study compared the ability of three groups of native English speakers - English-Mandarin bilinguals, English-Spanish bilinguals and monolinguals - to master words in an invented language that bore no relationship to English, Spanish or Mandarin. The bilingual participants mastered nearly twice the number of words as the monolinguals. The finding adds more support to the value of introducing another language to children at a young age.
 The bilingual advantage in novel word learning. Psychonomic Bulletin & Review. 16(4), 705 - 710.(2009).
Bilingual babies get a head start on executive functioning
A number of studies have pointed to benefits of being bilingual, but many people still believe that the experience of two languages in infancy may cause confusion and impair their acquisition of language. Now a new study shows that bilingual babies quickly adapt to different learning cues at seven months old compared with babies from single-language households. The study involved families in the Trieste area of Italy, where parents spoke to infants from birth using both Italian and Slovenian mother tongues. When bilingual and monolingual babies were first taught to look at one side of a screen in response to a sound cue (and in anticipation of a visual "reward" image of a puppet), then required to switch sides, it was found that bilingual babies quickly learned to look at the other side, but the monolingual babies never adapted to the change. The findings indicate that bilingualism gives an advantage above the purely linguistic, in executive function, which is consistent with other research indicating bilingual children have improved attention.
 Cognitive gains in 7-month-old bilingual infants. Proceedings of the National Academy of Sciences. 106(16), 6556 - 6560.(2009).
Anatomical advantage for second language learners
Based on the size of a small brain region called Heschl's Gyrus (HG) in the left hemisphere, researchers found they could predict who would be more successful in learning 18 words in an invented language (those predicted to be "more successful learners" achieved an average of 97% accuracy in identifying the pseudo words, compared to 63% from those deemed "less successful"). The size of the right HG was not important. The finding was surprising, given that this area, the primary region of the auditory cortex, is typically associated with handling the basic building blocks of sound — whether the pitch of a sound is going up or down, where sounds come from, and how loud a sound is — rather than speech per se.
 Volume of Left Heschl's Gyrus and Linguistic Pitch Learning. Cereb. Cortex. 18(4), 828 - 836.(2008).
Early music training 'tunes' auditory system
Mandarin is a tonal language, that is, the pitch pattern is as important as the sound of the syllables in determining the meaning of a word. In a small study, a Mandarin word was presented to 20 adults as they watched a movie. All were native English speakers with no knowledge of Mandarin, but half had at least six years of musical instrument training starting before the age of 12, while half had minimal or no musical training. As the subjects watched the movie, the researchers measured the accuracy of their brainstem ability to track three differently pitched "mi" sounds. Those who were musically trained were far better at tracking the three different tones than the non-musicians. The study is the first to provide concrete evidence that playing a musical instrument significantly enhances the brainstem's sensitivity to speech sounds, and supports the view that experience with music at a young age can "fine-tune" the brain's auditory system. The findings are in line with previous studies suggesting that musical experience can improve one's ability to learn tone languages in adulthood, and are also consistent with studies revealing anomalies in brainstem sound encoding in some children with learning disabilities which can be improved by auditory training. The findings are also noteworthy for implicating the brainstem in processing that has been thought of as exclusively involving the cortex.
 Musical experience shapes human brainstem encoding of linguistic pitch patterns. Nat Neurosci. 10(4), 420 - 422.(2007).
Why learning a new language may make you forget your old one
The common experience of having difficulty remembering words in your native language when you’ve been immersed in a new language is called first-language attrition, and new research has revealed that it occurs because native language words that might distract us when we are mastering a new language are actively inhibited. The study also found that this inhibition lessened as students became more fluent with the new language, suggesting it principally occurs during the initial stages of second language learning.
 Inhibiting your native language: the role of retrieval-induced forgetting during second-language acquisition. Psychological Science: A Journal of the American Psychological Society / APS. 18(1), 29 - 34.(2007).
Bilingualism has protective effect in delaying onset of dementia
An analysis of 184 people with dementia (132 were diagnosed with Alzheimer’s; the remaining 52 with other dementias) found that the mean age of onset of dementia symptoms in the 91 monolingual patients was 71.4 years, while for the 93 bilingual patients it was 75.5 years — a very significant difference. This difference remained even after considering the possible effect of cultural differences, immigration, formal education, employment and even gender as influencers in the results.
 Bilingualism as a protection against the onset of symptoms of dementia. Neuropsychologia. 45(2), 459 - 464.(2007).
How bilingualism affects the brain
Using a new technique, researchers have shed light on how bilingualism affects the brain. The study involved 20 younger adults of whom half were bilingual in Spanish and English. Similar brain activity, in the left Broca's area and left dorsolateral prefrontal cortex (DLPFC), was found in bilinguals and monolinguals when the task involved only one language. However, when the bilinguals were simultaneously processing each of their two languages and rapidly switching between them, they showed an increase in brain activity in both the left and the right hemisphere Broca's area, with greater activation in the right equivalent of Broca's area and the right DLPFC. The findings support the view that the brains of bilinguals and monolinguals are similar, and both process their individual languages in fundamentally similar ways, but bilinguals engage more of the neurons available for language processing.
The study was presented at the Society for Neuroscience's annual meeting on October 14-18 in Atlanta, Ga.
How does the bilingual brain distinguish between languages?
Studies of bilingual people have found that the same brain regions, particularly parts of the left temporal cortex, are similarly activated by both languages. But there must be some part of the brain that knows one language from another. A new imaging study reveals that this region is the left caudate — a finding supported by case studies of bilingual patients with damage to the left caudate, who are prone to switch languages involuntarily.
 Language Control in the Bilingual Brain. Science. 312(5779), 1537 - 1540.(2006).
An imaging study has found that fast language learners have more white matter in a region of the brain that’s critical for processing sound. The study involved 65 French adults in their twenties, who were asked to distinguish two closely related sounds (the French 'da' sound from the Hindi 'da' sound). There was considerable variation in people’s ability to learn to tell these sounds apart — the fastest could do it within 8 minutes; the slowest were still guessing randomly after 20 minutes. The 11 fastest and 10 slowest learners were then given brain scans, revealing that the fastest learners had, on average, 70% more white matter in the left Heschl's gyrus than the slowest learners, as well as a greater asymmetry in the parietal lobe (the left being bigger than the right).
 Brain Structure Predicts the Learning of Foreign Speech Sounds. Cereb. Cortex. 17(3), 575 - 582.(2007).
Language learning declines after second year of life
A study involving 96 deaf children who had received cochlear implants during their first four years of life has found that the rate of language learning was greatest for those given implants before they turned two. Children given implants at three or four years of age acquired language skills more slowly. The finding supports the idea that there is a 'sensitive period' for language learning, and suggests that deaf children should get cochlear implants sooner (it is still relatively rare for them to be given to children younger than two).
The findings were presented on 16 May at the Acoustical Society of America conference in Vancouver, Canada.
An imaging study of 25 Britons who did not speak a second language, 25 people who had learned another European language before the age of five and 33 bilinguals who had learned a second language between 10 and 15 years old found that the density of the gray matter in the left inferior parietal cortex of the brain was greater in bilinguals than in those without a second language. The effect was particularly noticeable in the "early" bilinguals. The findings were replicated in a study of 22 native Italian speakers who had learned English as a second language between the ages of two and 34.
Mechelli, A., Crinion, J.T., Noppeney, U., O'doherty, J., Ashburner, J., Frackowiak, R.S. & Price, C.J. 2004. Neurolinguistics: Structural plasticity in the bilingual brain. Nature, 431, 757.
Being fluent in two languages may help keep the brain sharper for longer
A study of 104 people aged between 30 and 88 has found that those who were fluent in two languages rather than just one were sharper mentally. Those fluent in two languages responded faster on tasks assumed to place demands on working memory, compared to those who were fluent in just English, at all age groups. This is consistent with the theory that constant management of 2 competing languages enhances executive functions. Bilingual volunteers were also much less likely to suffer from the mental decline associated with old age. The finding is consistent with other research suggesting that mental activity helps in protecting older adults from mental decline. The participants were all middle class, and educated to degree level. Half of the volunteers came from Canada and spoke only English. The other half came from India and were fluent in both English and Tamil.
 Bilingualism, aging, and cognitive control: evidence from the Simon task. Psychology and Aging. 19(2), 290 - 303.(2004).
Learning a second language may not be as laborious as believed
A study of adult learners of a second language has revealed that their brains still possess a surprising facility for learning words — much greater than the learner is consciously aware of. College students learning first-year French demonstrated brain activity that was clearly discriminating between real and pseudo-French words after only 14 hours of classroom instruction, although the students performed only at chance levels when asked to consciously choose whether or not the stimuli were real French words. The greater the exposure to French, the larger the difference in brain response to words and pseudo words.
 Neural correlates of second-language word learning: minimal instruction produces rapid change. Nature Neuroscience. 7(7), 703 - 704.(2004).
Beneficial effects of bilingual learning
A recent Canadian study comparing young monolingual children to bilingual found that bilingual children were much better at a non-language cognitive task. The 4-6 year old bilingual children were versed in a spoken language and a signing one. It was suggested that their higher cognitive skill was due to the increased computational demands of processing two different language systems.
Baker, S.A., Kovelman, I., Bialystok, E. & Petitto, L. A. (2003, November). “Bilingual children’s complex linguistic experience yields a cognitive advantage.” Presented at 2003 Society For Neuroscience conference. New Orleans, LA.
Both languages active in bilingual speakers
An imaging study involving bilingual Dutch and English speakers suggests that when a bilingual person is speaking a second language, the first language is always active and cannot be suppressed. It was thought that an environment of total immersion in a language would provide massive exposure to a second language and suppress the first language. However, it’s now suggested that a large component of language immersion involves learning a new set of cues to the second language. To test this, students with no exposure to German or Dutch were taught 40 Dutch words. Some students learned the words in association with their English counterparts and others learned the words in association with a picture. Some of the pictures were oriented in the normal way and others were upside down or otherwise skewed. People who learned the Dutch in association with an object that was oriented uniquely were faster to later translate English words into Dutch. The mis-oriented pictures served as a unique cue.
The research was presented at the Second Language Research Forum, October 18, in Tucson, Arizona.
Second language best taught in childhood
Sadly, it does appear that the easiest time to learn a second language is, indeed, in childhood. An imaging study has found that when grammatical judgement in the second language was compared to grammatical judgement in first language (as evidenced by performance on sentences with grammatical mistakes), there was no difference in brain activation in those who learned the second language as children. However, people who acquired the second language late and with different proficiency levels displayed significantly more activity in the Broca's region during second language grammatical processing. "This finding suggests that at the level of brain activity, the parallel learning of the two languages since birth or the early acquisition of a second language are crucial in the setting of the neural substrate for grammar."
 Early Setting of Grammatical Processing in the Bilingual Brain. Neuron. 37(1), 159 - 170.(2003).
Study finds there's a critical time for learning all languages, including sign language
It is generally believed that there is a critical period for learning a first language, and that children not exposed to language during this period will never fully acquire language. It is also thought that this might apply as well to second language learning — that those who learn another language after puberty can never become as fluent as those who learn it before puberty. A recent study suggests that this may also be true for non-verbal languages. Using functional magnetic resonance imaging (fMRI), it was found that patterns of brain activity in bilingual people who learned American Sign Language (ASL) before puberty differed from those who learned it after puberty.
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