Many people around the world grow up speaking two or more languages. This early acquisition of multiple languages leads to an important question: Do bilinguals think in two languages? Research on bilingual cognition suggests that the answer is complex, depending on factors like the bilingual’s proficiency in each language, age of acquisition, context of language use, and more.
Key Questions
Some key questions about bilingual cognition include:
– Do bilinguals have one integrated mental lexicon for both languages or separate lexicons for each language?
– Can bilinguals switch between languages seamlessly or is there always interference between languages?
– Do bilinguals think and perceive the world differently depending on which language they are operating in?
– How does being bilingual affect executive function skills like attention switching and inhibition?
Theories of Bilingual Cognition
There are several theories that aim to explain how multiple languages are represented and processed in the bilingual brain:
– The separate systems hypothesis proposes that bilinguals have distinct mental lexicons and language systems that can operate independently.
– The shared store model suggests bilinguals have one integrated lexicon and language processing system.
– The competition model views the two languages as competing for selection and separation requires inhibition.
– The concepts mediation model proposes bilinguals store conceptual representations separate from linguistic codes.
Factors That Influence Bilingual Cognition
Bilingual cognition is a complex phenomenon that is influenced by many factors:
– Age of acquisition: Early bilinguals may have different neural organization and processing than late bilinguals.
– Language proficiency: Balanced vs. dominant bilinguals may use languages differently.
– Overlap between languages: Cognates vs. languages with distinct orthography or phonology.
– Context of language use: Bilinguals adapt to communicate effectively in each context.
– Code-switching: Mixing languages requires joint activation and integration.
Evidence on Lexical Representation and Processing
So do bilinguals have one mental lexicon or two separate ones? Research using linguistic tasks provides mixed evidence:
Evidence for Separate Lexicons
– Bilinguals are slower to translate words than monolinguals are to name pictures, suggesting separate retrieval processes.
– Bilinguals experience less tip-of-the-tongue states for proper names in their dominant language.
– Bilinguals show weaker semantic priming between languages than within a language.
Evidence for Integrated Lexicon
– Cognates and interlingual homographs are processed differently than other words, indicating joint activation.
– Bilinguals experience cross-language syntactic priming from their two languages.
– Similar cortical regions are activated when bilinguals use each language.
Models of Bilingual Lexical Access
Models like the Bilingual Interactive Activation Plus (BIA+) model aim to account for findings suggesting both integrated and separate language processing. According to BIA+:
- Words from both languages are represented in one lexical network.
- Top-down factors like language context and task demands shape activation patterns.
- Competition and selection occur between words to choose the intended lexical item.
Thinking and Perceiving in Two Languages
Beyond lexical access and representation, researchers also examine if conceptual processing and thinking operate differently in a bilingual’s two languages.
Effects of Language on Cognition
Some evidence suggests language impacts bilingual cognition:
– Bilinguals categorize objects differently based on the language used.
– Time and space are perceived differently depending on the grammatical constraints of the language.
– Emotional words evoke stronger brain responses in the bilingual’s first language.
Concept Mediation Model
However, many studies show cognitive representation and processing are similar across a bilingual’s languages:
– Bilinguals perform similarly on non-verbal cognitive tasks regardless of test language.
– Second language immersion minimally impacts conceptual fluency and memory.
– Bilinguals maintain a common underlying proficiency across languages.
These findings support the concept mediation model where bilinguals access the same conceptual store from either language.
Code-Switching and Joint Activation
An interesting window into bilingual cognition comes from examining code-switching, or alternating between languages. Studies show:
– Bilinguals flexibly code-switch when appropriate without apparent cost.
– Code-switching involves parallel activation of both language systems.
– More interchangeable elements between languages increases code-switching.
– Code-switching patterns follow grammatical principles, suggesting an integrated system.
Overall, evidence indicates bilinguals must coordinate activation and control of two language systems to seamlessly code-switch between languages.
Effects of Bilingualism on Executive Functions
Mastering and using two language systems seems to confer cognitive benefits to bilinguals, especially for executive functions:
Evidence of Bilingual Advantages
– Bilinguals outperform monolinguals on tasks involving ignoring distracting information and task switching.
– Bilingual children develop inhibitory control at an earlier age.
– Bilingualism contributes to cognitive reserve and later onset of dementia.
Mechanism for Effects
The monitoring and control needed to manage two languages trains the brain’s executive control network and confers advantages:
– Goals must be maintained in the face of interference and competition between languages.
– Selecting the intended language involves overriding the unintended one.
– Code-switching requires dividing attention between systems.
Qualifications on Effects
However, some factors moderate the bilingual advantage on executive functioning:
– Balanced vs. dominant bilingualism – more equal proficiency provides greater benefits.
– Early vs. late acquisition – lifelong bilingual experience is important.
– Socioeconomic status and cultural differences between groups.
Conclusions
Summary
In summary, research suggests bilingual lexical access involves dynamic coordination between shared and separate language systems. Bilingualism confers cognitive benefits but the degree depends on individual circumstances. Overall, bilingual cognition relies on extensive interactive neural networks to support fluent dual language mastery.
Remaining Questions
Many open questions remain regarding bilingual cognition, including:
– How do multiple languages interact during speech comprehension and production?
– How are languages represented in the bilingual brain across the lifespan?
– How does bilingual education shape cognitive processes?
– To what extent do cultural representations get encoded into different languages?
As the world grows increasingly multilingual, understanding the cognitive mechanisms that support bilingualism remains an important endeavor with far-reaching implications.