Bilingualism: Consequences for Mind & Brain Limei Zhang & Liyu Cai

ADVANTAGES Of Bilingualism ?

? Bilingualism Dementia

Examine effects of Bilingualism on cognition in adulthood; Review recent studies: Examine effects of Bilingualism on cognition in adulthood; Explore possible mechanism for these effects Methods: Behavioral Neuro-imaging

What is Different about Bilingual Minds ?

Bilingual Children Symbol manipulation Reorganization Difference between form &meaning Ignore misleading information

Adult Bilinguals ?

Verbal Skills Executive Control Receptive vocabulary size Picture-naming tasks Comprehending &producing words Verbal fluency tasks High-level thought Multi-tasking Sustained attention

How do Bilinguals process languages ?

Joint Activation

Evidence of Joint Activation Cross-language priming Lexical decision Patient studies Imaging studies …

How is Executive Control Executed ?

Inhibition Local Inhibition Linguistic Performance Global Inhibition Linguistic Performance Cognitive Performance

Consequences of Joint Activation reduced speed of lexical access Linguistic outcome a role for activation Cognitive outcome enhanced attentional control

Conflict Tasks Measure of Attentional Control Flanker Task Simon Task Stroop Task

Red

Red

Green

Purple

Evidence from Neural-Imaging

fMRI Blood-oxygen-level dependent signal (Functional Magnetic Resonance Imaging) Blood-oxygen-level dependent signal

Brain Plasticity Grey Matter White Matter

Nature of Bilingual Advantages Evidences and counter-evidences

Evidences ☼Evidence 1(empirical) to manage two jointly activated languages Better control of attention ☼Evidence 2 other enhanced cognitive controls, such as LANGUAGE INHIBITION & CONFLICT MONITORING 1. older bilinguals outperform monolinguals in pure blocks of incongruent trials 2. Bilinguals outperform monolinguals in ‘interference suppression ’task when there are bivalent stimuli(not univalent stimuli) 3. Later diagnosis of dementia, AD(https://www.youtube.com/watch?v=20Sn0qz8L_M) due to cognitive reverse or brain reverse

Bialystok, Craik, and Freedman ’s study on hospital record Discovery : With all the other factors equal or similar ,bilinguals tend to be diagnosed with dementia (AD, Alzheimer ) 3-4 years later than monolinguals, thanks to better maintenance of cognitive function in healthy aging and postponing the onset of symptoms by continually stimulating physical or mental activity. Reliability: replicated results done by various scholars among different languages Validity: predictors are kept being ruled out as contributing factors , i.e. education/social status/culture/immigration ,etc. Causality: irrelevant to ‘good brain’

Counter-evidences  1. ONLY proved by recurrent congruent/ incongruent trials  2. preverbal advantage of bilingual children  3. no advantage shown in low-monitoring required conditions  4. no advantage shown on ‘response inhibition’ (univalent stimuli)

Preverbal advantage of bilingual infants No confusion over languages Phonic discrimination ability Phonic discrimination ability over Non-acoustic properties of language (renewed attention by bilingual infants of 8-month old) Better perceptual attentiveness to won visual rewards

Controversy over bilingual advantage As Cozalto and his colleagues pointed out : bilingual advantage is not due to the constant exercise of inhibition, but that learning to keep two languages separate leads to an improvement in selecting goal-relevant information from goal- irrelevant information Bilingual advantages are not fully discovered except for monitoring or difficulties conditions Specific task and precise language histories need to be studied

How bilingualism ?the possibility of a cumulative benefit for multiple languages. (multilinguals>bilinguals VS bilinguals>monolinguals) ? the degree of bilingualism required for these benefits to emerge. (no single factor decisive, i.e. Age, Fluency, Literacy, etc. ) ? Whether the similarity of the two languages matter(Spanish-English VS English-Chinese)

Conclusion As Peal and Lambert concluded :bilinguals have mental flexibility, meaning a superiority in concept formation and a more diversified set of mental abilities. Bilinguals outperform in inhibition, selection, switching , sustaining attention, working memory , representation and retrieval. Fear and anecdotes served as counter-evidence to show that bilingualism may bring in retardation, academic struggle and language confusion. There is still much we do not know about the effect of bilingualism on the mind, the neural correlates of those effects, and the causal components of the experience that lead to them . 　ＳＯ　ＬＥＴ‘Ｓ　ＣＯＮＴＩＮＵＥ　ＯＵＲ　ＰＲＯＢＥ

Questions From your own experience , did you experience TOT phenomenon in using a language while the equivalence in another language emerged? Do you think you have a good inhibition ability to control it? Do you believe the multicompetence /bilingualism brings in retardation or personal struggle? Share your story or any anecdote.