Presented by Kimberley Chen

1. Native Language Shifts Across Sleep-wake States in Bilingual Sleep-talkersJuan A. Pareja, Eloy de Pablos, Ana B. Caminero, Isabel Millán and José LDobato Presented by Kimberley Chen

2. Introduction • What is sleep-talking? • Common parasomnia that range from mumbled nonsense to coherent sentences but without detailed awareness of the event • Occurs spontaneously; sometimes due to emotional stress • Happens during NREM sleep and REM sleep • More frequent in children and teenagers than in adults

3. Previous research & Research Question • Multi-language patients always use their dominant language during sleep-talking episodes • To study the language used by healthy bilingual children during episodes of sleep-talking

4. Methods • Subjects: • 3 bilingual schools in Northern Spain • 681 children ( 336 males and 341 females , 4 unknowns) • Age 3-17 (mean age: 9.0; SD: 2.6) • 1000 parents agreed to participate too • Languages: Spanish & Euskera

5. Methods • Procedure • Parents had to complete self-administered questionnaire • Sample questions: • What was the 1st language learned by your child? • Does your child sleep talk? • If you child sleep-talks, what language does he/she speak while sleeping? *To ensure reliability in answers, parents were told to skip any question in doubt and they could call the investigator to discuss any doubts

6. Results • Sleep-talking occurred in 56.3% of the 681 children

7. Results

8. Results Percentage of subjects Native Language

9. Discussion • Dominant bilinguals found to use native language during episodes of sleep-talking • <4% found to use non-dominant language persistently during sleep-talking • Balanced bilinguals showed tendency to sleep-talk in either of the two native languages without preference • Environmental factors like cultural and social atmosphere tip balance towards one language

10. Discussion • Differences in intra-hemispheric organization • Two languages learnt early in infancy at the same time  Represented in same cortical areas of dominant cerebral hemisphere • One language learnt first and then second language learnt  Represented in different brain areas

11. Discussion • Emotional stress • Released in an unconscious way during episodes of sleep-talking • Some elements with negative content* usually occur in second-acquired language. * Research done on bilingual patients with auditory hallucinations: hear aggressive voices in second language and protective voices in native language

12. Conclusion • Predominance of bilingual subjects used their native language during episodes of sleep-talking

13. Strengths & Limitations Strengths • Easy to read • Large sample size • Balance of genders • Limitations • Only one region of the world was tested • Parents may be bias • Did not link to specific brain areas • No clear hypothesis

14. Future experiments • To test on multi-linguals (more than 3 languages) • Test other areas in the world where bilingualism exists • Narrow the age range • Use a voice recorder to record sleep-talking

15. Thank you for listening!!!  Any questions?