The project shows the results of experiments examining the consequences of lifelong bilingualism on cognitive and linguistic performance. Typically, research has shown that bilingualism leads to disadvantages in linguistic ability but advantages in executive control, a crucial cognitive ability
Many people who are bilingual are taught both languages from the start of their lives. One language is normally spoken at home, and the other is spoken at school. Bilingual children are raised learning two words for one object, whereas monolingual children are raised learning only one word per object. For example, a bilingual child learning both French and English would learn that “house” and “maison” are the same object. Yet a monolingual English-speaking child would only learn the one word: “house.” Because of this, bilingual children must learn twice the amount of words than monolingual children.
Bilingual children must then apply this vocabulary to two different language systems (Marian, 2009). Bilingual children, tend to have a lower vocabulary level than their monolingual counterparts. Vocabulary is as the number of conceptual representations that have lexical labels, not the number of lexical items. Monolinguals learn more lexical labels for words than bilinguals; bilingual learners learn more lexical items than monolingual learners.
Because of this, bilingual children tend to have a lower vocabulary level than monolingual learners. Bilingualism in children is also normally tested in school in only one language. This provides an inaccurate representation of their language skills (Marian, 2009). Second language acquisition occurs when you introduce a second language to a child after the establishment of the first language. It is more difficult for a child who has experience with second language acquisition to become fluent like a child who has been bilingual essentially from birth.
Many factors can contribute to this decline in language learning ability(Karavasili, 2017). Children who grow up bilingual are able to use both sides of their brains. As a result of the plasticity of their brains. Those learning a second language after puberty tend to only use the left side of their brains since they have less plasticity in them. This is the cause of Cummins’ threshold theory (Nacamulli, 2015).
Strengths of Bilingualism on Cognition
A study by Debbie Gooch tested 243 children who were at risk for developing dyslexia. A learning disorder involving problems with reading, along with a control group that did not appear to be at risk. There were three groups of subjects. Those with a family history of dyslexia, those with language development considered slower than normal. Lastly, the control group. Subjects took a test assessing their executive function and language skills at the ages of four through six. At the ages of six and seven, parents and teachers rated the subject’s behavior and attention skills assessing their executive function.
There appeared to be a strong correlation between executive function and language at each of the testing stages. Executive function is a construct that involves processes such as memory, attention control, and behavioral inhibition. The subjects’ executive function scores from their tests at age six were good indicators of their behavior and attention skills at ages six and seven, but language scores did not have an affect. From this study, it appears that executive function and language seem to be connected during early years of childhood, as subjects with language disabilities also had attention and behavior deficiencies (Gooch et al., 2016).
Cognitive Consequences of Bilingualism
Research has overwhelmingly shown that when a bilingual person uses one language, the other is active at the same time. When a person hears a word, he or she doesn’t hear the entire word all at once. The sounds arrive in sequential order. Long before you complete a word, the brain’s language system begins to guess what that word might be by activating lots of words that match the signal. If you hear “can,” you will likely activate words like “candy” and “candle” as well, at least during the earlier stages of word recognition. For bilingual people, this activation not only depends on a single language; auditory input activates corresponding words regardless of the language to which they belong.
Some of the most compelling evidence for language co-activation comes from studying eye movements. We tend to look at things that we are thinking, talking, or hearing about. A Russian-English bilingual person asked to “pick up a marker” from a set of objects would look more at a stamp than someone who doesn’t know Russian, because the Russian word for “stamp,” “marka,” sounds like the English word he or she heard, “marker.”4 In cases like this, language co-activation occurs because what the listener hears could map onto words in either language.
Furthermore, language co-activation is so automatic that people consider words in both languages even without overt similarity. For example, when Chinese-English bilingual people judge how alike two English words are in meaning. Their brain responses depend on whether or not the Chinese translations of those words are similar. Even though the task does not require the bilingual people to engage their Chinese, they do so anyway.