In Search of Objectivity: Understanding and Mitigating Ethnocentrism’s Influence on Historians (Blog Post 3)

With this final blog post, my project comes to an end.  I combined my research into a final essay, which is attached to this post.  Overall, I was satisfied with the amount of time I put into each category of research.  Perhaps I overdid the science portion of the project, reading a few dozen articles, a full book, and parts of several others, which left me less time for the history part.  I feel that the time was well spent, however, as the scientific understanding of ethnocentrism was the backbone of my project.  I also learned about fields in which I have little training, such as anthropology and sociology.

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Reflection

In my research I’ve learned a lot about language acquisition and processing and it has opened my eyes to how the brain is able to work and process in such a complex way.  First, I learned that when learning a second language, your brain uses the strong preexisting connections from your first language to learn the second faster and more effectively.  Also, there are specific areas of the brain that are associated with particular components of language and it is intriguing as to how we are able to determine the function of these specific areas.  These researchers as well as many others have suggested a critical period for learning languages which is pretty much up until puberty and then there is slight aphasia causing less plasticity or flexibility in the neurons.  One study had supporting evidence for this hypothesis given that one area of the brain was only activated in native signers and those that learned it after puberty did not have any activation at all in this area of the brain.  While there has been other evidence supporting this I think it’s important to point out that this decline in the plasticity and ability to learn a language is highly variable between individuals.  Another paper had provided a possible hypothesis for why babies are able to learn any language and that is because when they are born their brains are wired to understand any language but as their parents and others talk to them in their native language the babies’ are able to differentiate sounds and begin to piece together components of the language.  This researcher also proposed a social gating hypothesis stating that it is very important that infants have social interactions because without this they can’t truly become fluent in their native language and this could be an explanation as to why other animals who have computing systems as great as ours don’t use language.  In a more structural sense, one study found that there was less gray matter in bilinguals than people who learned a second language later in life which could mean that they have more streamlined and efficient neural systems, but the opposite has been found in many other studies where bilinguals have more gray and white matter volume than those who learned a second language after puberty or are monolinguals.  One suggestion in this paper that I thought was fascinating talked about Alzheimer’s and how the greater white matter density in bilinguals is able to compensate for the gray matter atrophy that occurs and therefore deters the disease.  This was of particular importance to me because I previously worked in a lab that investigated a possible cause for Alzheimer’s that involved the cell cycle and from that research I truly understand the importance of having anything that is able to deter Alzheimer’s from progressing in an individual.  Another study I read asked the exact question I did, what connections in the adult brain allow for better learning of a second language?  They found that for lexical retrieval success a stronger connection between the left insula/frontal operculum and the left posterior superior temporal gyrus was needed and the stronger the connection the greater the improvement in the individual.  Generally, the preexisting connections between these areas of the brain are what allow certain adults to have more ease in learning a second language compared to others.  A different study looked at individuals who were exposed to and learned a second language for 5 months and found that those who had a greater increase in proficiency had a greater increase in gray matter density in areas that are associated with language.  One interesting point that a different paper investigated was the effect of your first language on your ability to learn a second language.  They found that activation in an area of the brain that was earlier in Koreans than Chinese and this could be explained by the fact that Korean has somewhat similar structures to English while Chinese has no correlational structure.  Upon further research however, they found that their language proficiency determines the detection of their measurements rather than the grammatical structures, essentially meaning that the first language does not necessarily make a difference in the long term knowledge of the language but those with completely different structures might take longer or have a more difficult time learning it.  Lastly I read a dissertation on adult second language acquisition and the neural substrates and found that there is most likely a dual-system since regular and irregular verbs are processed differently but it’s not a simple separation between words and rules, it is more complex than that.  Then they looked into syntax and semantics and found that syntactical errors activated a different part of the brain than they were expecting but this has been found in other experiments previously, and for semantical errors it activated an area of the brain that has been shown to be associated with semantics.  In their last study they found that people who were native signers had greater activation in their right hemisphere compared to people who learned to sign after puberty.  There was also a region of the right hemisphere that was not activated at all in the late signers suggesting that there is a critical period for the plasticity in this area of the brain.  Overall, I learned a lot from this research and have found it very interesting along the way, I hope that more research is done to get to the real bottom of my question but during my research I truly realized one thing: the brain is extremely complex and fascinating.  

The Dissertation

In my research I came across a dissertation that discusses how adults learn a second language and the effects on the brain.  First it talks about the individual components of language like sound structure, structure of words, sentence structure, meaning of words, and the meaning of more complex sentences.  The beginning discusses the different approaches to how we are able to differentiate between word forms and past tense differentiations.  There has been lots of banter and debate about which system and structure is truly how the brain works but as of now we’re still unsure as to how the brain is able to determine correct and incorrect words and sentences.  On to acquisition, this paper also suggests that there is a critical period as to when we are best able to learn a second language, but that the declines after this period are highly variable between individuals. The first study mentioned in this dissertation investigated potentials in the brain when participants read English sentences either with correctly conjugated past tense verbs or when they were incorrectly in their infinitive.  There have been many debates as to the system under which the brain works, and there are suggestions of a dual-system where we have all of the words in one section of the brain and rules in the other and then apply the rules to the verbs, or it could be a  single-system where it is the organization of the lexicon rather than separate processes.  The first experiment in this study included sentences with only alterations in the verbs and they found that there were significant differences in the trials with the correct regular verbs and the incorrect regular ones in all 100 ms time frames after the stimulus, however with the irregulars there was no significance between the correct and incorrect in the 100-1000 ms time frame.  These results suggest that regular and irregular conjugation is treated differently by the brain in the early stages of processing.  The second experiment they included sentences that were syntactically incorrect or there were violations in the meaning of the sentence this was done to ensure that the participants hadn’t been using another process in the previous experiment because they were just focusing on the verb rather than the sentence.  The results for the regular verbs were similar to those in the first experiment but the results for the irregulars were slightly different in that there were significant interactions in the 500-900 ms time frame and for the sentence structure violations there was a significant effect on the wavelengths that were measured compared to the controls.  These results could mean that these are similar processes given that they have similar effects on the brain but at slightly different times.  Experiment three had identical procedures and stimuli to experiment two, but they altered the preceding words to the verbs to ensure that it didn’t affect their measurements.  The results from the regular verbs differed from both of the preceding experiments, the irregular verb results were the same as in experiment two, and the sentence structure results were similar to what was found in experiment two.  Overall, this study suggests that regular and irregular verbs are treated differently at the neural level, and possibly supports the dual-systems hypothesis.  The second study discussed in this paper looked into the brain regions that are involved in syntactic and semantic processing.  Before technology really skyrocketed linguists would observe people who had a lesion in a certain part of their brain and see if it affected their speech or language in any way, the data from these studies have been further confirmed by technological data from healthy individuals.  In this experiment they had right-handed males read sentences which were correct or had a syntactical, words in the wrong order, or semantic, a word doesn’t make sense, error.  Syntactic violations had a greater activation in regions in the superior frontal gyrus and these locations corresponded with Brodmann’s area and the semantic violations had greater activation in the temporal and temporo-parietal regions of the brain.  The regions that were activated by syntactic violations were odd in that they weren’t expecting this, but they were not unique since previous studies have had similar findings, they were surprised however that Broca’s area was not activated but they suggested that it might be activated only to the same extent as it is with a correct sentence.  In regards to the areas activated by the semantic violations they have been previously shown as storage regions but overall the regions have previously been shown to be involved in semantic memory, both encoding and retrieval of information, and storage.  The third study examined in this dissertation focuses on the neural regions involved in language processing of bilinguals of English and ASL compared to the age of acquisition.  It has been shown previously that there is significant activation in the right hemisphere of bilinguals and deaf signers suggesting that sign language demands processing in the right hemisphere compared to oral languages.  When looking at the results from the participants reading English sentences they were virtually identical and there were equivalent activations in the right hemisphere along the anterior and middle superior temporal sulcus in both groups when reading ASL sentences, suggesting this activation is irrespective of the age of acquisition.  While the areas of activation were the same, there was significantly less activation in the late signers than in the native signers and late signers have a strong left hemisphere dominance when reading ASL while native speakers have no left hemisphere dominance when reading ASL.  There was also significant activation in one area of the right hemisphere in native signers but was not activated at all in late signers, suggesting that there is a critical period for this region as well as generally using the right hemisphere to understand sign language.  Overall from this dissertation, they supported the theory of a dual-system given that the regular and irregular violations had different activations at different time points, suggesting there is different processing at the neural level for regular and irregular verbs.  They also found that syntactic violations activate a part of the brain where they weren’t expecting to get results but semantic violations were found to activate areas that previously were shown to be involved in semantic-pragmatic processing.  Lastly, they found that in native signers there was activation in one region of the right hemisphere that was not present in late signers, even though they generally had similar areas of activation in the right hemisphere, suggesting that plasticity in this region declines with aging and maturation.

In Search of Objectivity: Understanding and Mitigating Ethnocentrism’s Influence on Historians (Blog Post 2)

The second part of my research is now complete.  In the first part of my research, I focused on the science behind ethnocentrism.   I now examined the purported impacts of ethnocentrism on history.  For this research, I relied primarily on two books: The Colonizer’s Model of the World by J.M. Blaut and White Mythologies by Robert Young.  I also read an article by Jörn Rüsen about attempting to overcome ethnocentrism in history.

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