Electrophysiological Indices of Biological Mo*on and Audio-­‐Visual Integra*on in Infants at Risk for Au*sm Hannah Reuman, Rachael Tillman, Emily Levy, Max Rolison, Giulia Righi, Cora Mukerji, Adam Naples, Marika Coffman, Peter Hashim, & James McPartland McPartland Lab Yale Child Study Center, New Haven, CT BACKGROUND NR
Biological MoGon (BM) •  Perceptual sensi*vity to BM is evident in infants as young as 2 days old, sugges*ng the presence of a innate neurological perceptual mechanism for processing biological mo*on (Simion et al., 2008). •  Typically-­‐developing 8-­‐month-­‐old infants demonstrate greater right hemisphere ac*va*on compared to leD hemisphere ac*va*on during percep*on of BM, similar to that of adults, sugges*ng that the processing of BM begins by eight months of age (Harai & Hiraki, 2005). •  The percep*on of BM may be atypical in children with au*sm (Klin et al., 2009). Audio-­‐visual Synchrony (AVS) •  Detec*on of temporal con*ngency between auditory and visual events is another founda*onal skill for interpre*ng socially-­‐relevant informa*on. •  Electrophysiological studies in typically-­‐developing adults and children reveal neural facilita*on to mul*sensory events, marked by a significantly more nega*ve response to mul*sensory s*muli rela*ve to the sum response of two unimodal s*muli (Hyde et al., 2010; Brandwein et al., 2011). Normal Risk Infants (NR) (%#
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STIMULUS ONSET
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STIMULUS OFFSET
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STIMULUS ONSET
2000-2250 ms
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100 trials total: •  25 point-­‐light display walkers moving right •  25 walkers moving leD •  25 scrambled paberns moving right •  25 scrambled paberns moving leD •  EEG recorded con*nuously at 500 Hz using 128-­‐channel +
Hydrocel Geodesic Sensor Nets. •  ERPs segmented to s*mulus onset, hand-­‐edited for ar*fact, and averaged referenced. •  Peak amplitude for the N200 was extracted in the Biological Mo*on Paradigm and the Audio-­‐visual Synchrony paradigm. •  Minimum amplitude was analyzed using Repeated Measures ANOVA (between-­‐subjects: risk (HR/NR); within-­‐subjects: condi*on (BM/SM). Acknowledgements: Autism Speaks Translational Postdoctoral
Fellowship (Naples), Simons Foundation 94924 (Klin, Pelphrey,
McPartland), NIMH K23MH086785, R01MH100173 (McPartland),
NARSAD Atherton Young Investigator Award (McPartland).
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90 trials total: •  30 audio only •  30 visual only •  30 audiovisual Figure 1: BM and AVS N200. Data were averaged across 4 electrodes for the BM N200 recording site (91, 92, 96, 97) and 3 electrodes for the AVS N200 recording site (74, 81, 82). +%%#
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N200 Figure 3: Amplitude of grand averaged waveforms elicited by audio-­‐visual sGmuli and summed response to audio only and visual only sGmuli in 9 to 12 month infants. Latency (ms) Audio-­‐visual Synchrony: • 
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•  HR infants between 6 and 9 months display comparable neural response to BM. •  Atypicali*es in social percep*on may emerge aDer the first year of life. •  HR infants may have norma*ve response to BM, with social dysfunc*on emerging during processing of more complex biological s*muli. •  HR infants between 9 and 12 months display atypical mul*sensory integra*on. •  Deficits in social percep*on may occur secondary to more basic perceptual anomalies. FUTURE DIRECTIONS 9 months 750-1100 ms
Figure 2: Grand averaged waveforms for BM and SM for HR and NR infants at 6 month and 9 month Gme points. PRELIMINARY RESULTS Biological MoGon: NR infants exhibited a significantly more nega*ve AVS amplitude compared to the summed auditory and visual amplitude (t(7) = -­‐3.295, p=.01). HR infants did not demonstrate a significant difference between AVS amplitude and summed auditory and visual amplitude (p>.05). CONCLUSIONS !%$
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PARTICIPANTS & METHODS A
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High Risk Infants (HR) 6 months Current Study •  Two experiments assessed electrophysiological brain responses to BM, scrambled mo*on (SM), and AVS in infants at elevated risk for ASD in the first year of life. •  We evaluated the hypotheses that that, rela*ve to normal risk (NR) infants, high risk (HR) infants would display: •  Atypical social percep*on, i.e., decreased differen*a*on between BM and SM •  Atypical sensory percep*on, i.e., weakened neural facilita*on to AVS Biological Mo*on Paradigm At 6 months of age, both HR and NR infants exhibited a more posi*ve amplitude to BM rela*ve to SM. Neither HR nor NR infants exhibited significant differen*a*on between the two condi*ons (p>. 05). At 9 months of age, NR but not HR infants con*nued to demonstrate a more posi*ve amplitude to BM. Neither HR nor NR infants demonstrated significant differen*a*on between the two condi*ons (p>.05). • 
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Ongoing data collec*on will follow infants through diagnos*c outcomes at 36 months. •  Compare results in infants who develop ASD versus high-­‐risk infants who develop typically. Future work will inves*gate the developmental unfolding of social and sensory percep*on and the influence of early developmental abnormali*es on subsequent development. REFERENCES Simion, F., Regolin, L., & Bulf, H. (2008). A predisposi*on for biological mo*on in the newborn baby. Proceedings of the Na2onal Academy of Sciences of the United States of America, 105(2), 809-­‐13. doi:10.1073/pnas.0707021105 Hirai, M. & Hiraki, K. (2005). An event-­‐related poten*als study of biological mo*on percep*on. Brain Res Cogn Brain Res., 22(2), 301-­‐4. Klin, A., Lin, D., Gorrindo, P., Ramsay, G., & Jones, W. (2009). Two-­‐year-­‐olds with au*sm orient to non-­‐social con*ngencies rather than biological mo*on. Nature, 459(7244), 257-­‐61. doi: 10.1038/nature07868 Hyde, D., Jones, B., Porter, C., & Flom, R. (2010). Visual s*mula*on enhances auditory processing in 3-­‐month-­‐old infants and adults. Dev Psychobiol, 52(2), 181-­‐9. doi: 10.1002/dev.20417 Brandwein, A., Foxe, J., Russo, N., Altschuler, T., Gomes, H. & Molholm, S. (2010). The development of audiovisual mul*sensory integra*on across childhood and early adolescence: A high-­‐density electrical mapping study. Cerebral Cortex, 21 (5), 1042-­‐1055. doi: 10.1093/cercor/bhq170