Working memory and second language learning Graham Hitch, Meesha Warmington & Swathi Kandru

Visuo-spatial Sketch Pad Phonological Loop Central Executive Baddeley & Hitch, 1974; Baddeley, 1986 Multi-component model of working memory

Converging evidence for multiple components Multiple capacities Patterns of dual-task interference Individual differences Developmental differences Selective impairments Developmental disorders Neural bases

Multiple capacities Digit span, Word span, Non-word repetition Pattern span, Corsi span Counting span, Reading span, Listening span, Operation span -Phonological loop -Visuo-spatial sketchpad -Central executive plus phonological loop

Gathercole, Pickering, Ambridge & Wearing, 2004 Individual differences

Baddeley (2000) Revised model of working memory

(Chun et al, 2011)

Enhanced cognitive abilities include Working memory Executive skills (e.g. Bialystock et al., 2006) Phonological STM (e..g. Papagno & Vallar, 1995) Word learning (e.g. Kaushanskaya & Marian, 2009) Issues Assessment of working memory and attention Relationships between executive skills, phonological STM and word learning in bilinguals (e.g. Bradley et al., 2013) Bilingual adults

Present study Hindi – English sequential bilinguals vs English monolinguals Do we find the usual cognitive strengths? Are there differences in what predicts word learning in bilinguals?

General cognitive ability Wechsler Abbreviated Scale of Intelligence (WASI, Wechsler, 1999) Vocabulary Matrix reasoning Automated Working Memory Assessment (AWMA, Alloway, 2007) Phonological STM Digit recall Nonword recall Visuo-spatial STM Dot matrix Block recall Verbal executive Listening recall Backwards digits Visuo-spatial executive Odd one out Spatial recall

External attention (perceptual selection) Flanker task (e.g. Fan et al, 2002) 2AFC RT to central target Congruent trial  Incongruent trial  RT (Incongruent-congruent)

Internal attention (Inhibitory control) Stop signal RT task (Logan et al., 1984) simple RT present GO signal after variable foreperiod (1000, 3000, 5000 ms) on 25% of trials STOP signal occurs after the GO (SOA 200, 400, 600 ms) respond as rapidly as possible on GO trials while not responding on STOP trials Horse-race model  Stop signal RT

Internal attention (Inhibitory control) Stop signal RT task (Logan et al., 1984) Horse-race model

WASI subtests MonolingualsBilingualsp Vocabulary64.7 (5.0)63.7 (6.6)ns Matrix Reasoning59.4 (3.6)61.7 (3.5)ns Participants English monolinguals(N=2014 malesage M=21:7) Hindi-English bilinguals (N=2010 malesage M=23:5)

Self-reported language of bilinguals Self-rated language proficiency (scale 1-7) Hindi6.3 (1.0) English5.9 (0.6) Self-rated language usage (scale 1-5) Hindi family4.3 (1.2) friends3.5 (1.2) work1.4 (0.7) English family3.9 (1.0) friends4.4 (0.7) work4.8 (0.5)

Automated Working Memory Assessment MonolingualsBilingualsp Verbal STM Forwards digits 91 (6)104 (11)** Nonword recall106 (16)119 (12)** Visuo-spatial STM Dot matrix102 (13)111 (8)* Block recall 94 (15)113 (16)** Verbal Executive Listening recall101 (11)107 (13)ns Backward digits 98 (15)114 (12)** Visuo-spatial Executive Odd one out104 (12)114 (11)** Spatial recall100 (13)114 (11)**

Executive Tasks MonolingualsBilingualsp Stop Signal Go RT (ms)684 (138)524 (85)** SD RT (ms)211 (98)133 (29)** Accuracy (%)99 P(i) (%)68 (11)69 (12)ns SS RT (ms)284 (138)124 (85)** Flanker Congruent RT (ms)478 (148)515 (121) Incongruent RT (ms)537 (148)575 (132) Interference (ms) 57 60ns Accuracy (%)100

8 low frequency English words Translated and recorded in Spanish by a native speaker Rated familiarity by native English speakers <2 (scale 1 – 5) Paired with 8 unfamiliar pictured objects Word learning: materials

Word learning pocedure Familiarisation Present each of the 8 objects with its spoken name 3 blocks Learning Present each object, participant attempts to name, given corrective feedback Stop at criterion of 6 correct or if sooner 10 trials Test Name each object in turn, no feedback (Immediate) Repeat 1 day later (Delayed)

Word learning MonolingualsBilingualsp Trials to criterion (out of 10)4.1 (1.9)2.7 (1.1)** Immediate object naming5.8 (1.3)6.8 (0.7)** Delayed object naming4.8 (1.4)6.1 (0.8)**

Word learning

Hierarchical regressions Monolinguals (N=20)Bilinguals (N=20) BSE BtβR2R2 B tβR2R Wasi vocab.00.01< <1.00 Digit recall < *.46 Nonword recall.01.07< Listening recall * *.58 Backward digits.03.05< Flanker < Stop signal *.56

Conclusions Enhancement of selective components of attention in Hindi-English bilinguals Internal inhibitory control but not external perceptual selection (Replicated with further N=46 ptpts) Enhanced word learning in bilinguals Related to enhanced executive and verbal working memory skills Different from monolinguals?

Thanks for listening Special thanks to Meesha Warmington and Swathi Kandru

Correlations (N = 40 combined over language groups) WASI vocab Digit recall Nonword recall Listening recall Backward digits Stop signal FlankerWord learning Wasi vocab Digit recall.38*.42**.51**-.39*.00.48** Nonword recall.34*.49** Listening recall.48** ** Backward digits -.45** ** Stop signal * Flanker -.10

Word learning