Dr Victoria Leong, University of Cambridge and Nanyang Technological University, speaks about the social dynamics of adult-infant neural synchrony

1. Synchrony through gaze :
Mapping the neural social network of infants
Dr Victoria Leong
Department of Psychology, University of Cambridge
Nanyang Technological University, Singapore
1

2. 2
• Synchrony creates social connectedness
(see Marsh et al, 2009 for review)
• Infants are more helpful to synchronous strangers
(Cirelli et al, 2014)
Synchrony : An affiliative mechanism

3. 3
• Parents and infants synchronise on multiple levels
– Gaze
– Behaviour
– Emotions
– Physiology (heartrate, arousal)
(Kaye & Fogel, 1980; Cohn & Tronick, 1988;
Feldman et al, 2011; Waters et al, 2014)
Do brains also synchronise? (YES)
How and for what purpose?
Parent-child synchrony
Behaviour states =
Protest, disengage, attend, play

4. Research Areas
Neuro-Social Mechanisms of Learning
Adult-Infant Neural
Synchronicity
• Eye contact
• Joint
attention
• Name use
SYNCHRONY
CUES
• Learning
• Communication
• Interpersonal
trust
SUPPORT FOR

5. 5
• From birth, infants prefer
Direct gaze (Farroni et al, 2002)
• Gaze supports infant
communication (Bloom, 1975)
• Gaze-following ability
predicts language learning
(Brooks & Meltzoff, 2008)
Gaze : An early communication signal
Vocalisations
/min
(smile/touch)
Does gaze act as a
“synchronising cue”
for interacting brains?

6. 6
Gaze and adult-infant neural synchrony
• Adult-infant dyads (9 months old)
• General Partial Directed Coherence (GPDC)
– Directed measure of (Granger)-causality
• Theta and Alpha bands only (no speech artifacts)
• Significance thresholding with surrogate shuffled data
(N=17) (N=19)

7. 7
Predictions
• E1 : Uni-directional influences A  I
E2 : Bi-directional influences A  I & I  A
• Direct = Direct-Oblique >> Indirect gaze
• More vocalisations with Direct gaze
Direct Indirect Direct-Oblique

8. 8
Expt 1 (vid) : Neurosocial network
✓

9. 9
Expt 2 (live) : Neurosocial network
✓ ✓

10. • Gaze triggers phase-resetting so that adults’
and infants’ oscillation patterns align ( sync)
• In this aligned state, information is optimally
transmitted from speaker to listener
(i.e. Adult is ready to speak when Infant is ready to listen)
10
What’s going on?
Are infants really more receptive during Direct gaze?
Indirect Direct

11. 11
Infants’ internal networks during gaze
Direct Indirect Direct-Oblique
Direct
Indirect
Direct-Oblique
Theta Alpha
THETA

12. Expt 1 (Vid) Expt 2 (Live)
*p<.05
12
Infants’ vocalisations
Direct
Indirect
Direct-Oblique

13. • Infants who make a greater effort to communicate
(vocalise longer) influence the adult more
– Caveat : this only works if the adult is looking and live..
• Infants help to maintain dyadic synchronicity! 13
Infants’ vocalisations

14. 14
Do other auditory signals work too?
“Tom”
*
*
* p<.05

15. 15
0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2
0
0.1
0.2
0.3
0.4
0.5
0.6
Time (s)
Amplitude
• Infants can connect to and help
maintain neural social networks
with adults
• Social signals like gaze and name-
calling are neural “synchronising
cues”
• A high-synchrony, joint-networked
state may support communication
and learning
Sync with me!
Conclusions : Synchrony through gaze

16. Dr Sam Wass (UEL)
Co-investigator
16
Dr Kaili Clackson
Post-doc
Tardis tamer &
Baby charmer
Stani Georgieva
EEG specialist
Brainwave guru
Thanks to the research team…
Elizabeth Byrne
(MRC-CBU)
Experimental material
Most consistent singing
• Our kind volunteers who assisted with hours of video
coding and baby distraction
• Our brave mums and babies
• Friends and family for supporting and believing in us!

17. Thanks for support from
ESRC UK
Nanyang Technological University
Rosetrees Trust
Isaac Newton Trust
British Academy
Leverhulme Trust
Keep up with us at:
• @Baby_LINC
• @DrVLeong
• http://www.baby-linc.psychol.cam.ac.uk/
Bye bye!