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Right but not left hemispheric discrimination of faces in infancy

Nature Human Behaviour volume 2, pages 67–79 (2018)Cite this article

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Abstract

The ontogeny of the functional asymmetries of the human brain is poorly understood. Are they a consequence of differential development based on competition mechanisms, or are they constitutive of the human brain architecture from the start? Using structural magnetic resonance imaging and a face-discrimination electroencephalography paradigm with lateralized presentation of faces, we studied face perception in infants over the first postnatal semester. We showed that the corpus callosum is sufficiently mature to transfer visual information across hemispheres, but the inter-hemispheric transfer time of early visual responses is modulated by callosal fibre myelination. We also revealed that only the right hemisphere shows evidence of face discrimination when presented in the left visual hemifield. This capability improved throughout the first semester with no evidence of discrimination in the left hemisphere. Face-processing lateralization is thus a characteristic of the infant’s extra-striate visual cortex, highlighting the differential left–right organization of the human brain already established in infanthood.

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Fig. 1: EEG experimental paradigms.
Fig. 2: P1 component.
Fig. 3: Structure–function relationships.
Fig. 4: Grand averages according to the visual hemifields.
Fig. 5: Grand averages according to the face conditions.
Fig. 6: Comparison of N290 and P400 components across face conditions.

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Acknowledgements

This research was supported by grants from the Fondation de France and the Fyssen Foundation. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. We thank all the infants and their parents who participated in this study as well as G. Santoro and the medical team of UNIACT at Neurospin, who helped to carry out the experiments; C. Kabdebon, P. Barttfeld, J. Lebenberg and F. Leroy for their help with the EEG and MRI analyses; and E. Moulton for proofreading the text. We thank our colleagues for providing their pictures to be used as stimuli in our paradigm.

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  1. Cognitive Neuroimaging Unit, CEA DRF/I2BM, INSERM, NeuroSpin Center, Université Paris-Sud, Université Paris-Saclay, Gif-sur-Yvette, France

    Parvaneh Adibpour, Jessica Dubois & Ghislaine Dehaene-Lambertz

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  1. Parvaneh Adibpour
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All authors contributed to data collection, analysis, interpretation and drafting of the Article. J.D. and G.D.-L. designed the experiments.

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Correspondence to Ghislaine Dehaene-Lambertz.

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Adibpour, P., Dubois, J. & Dehaene-Lambertz, G. Right but not left hemispheric discrimination of faces in infancy. Nat Hum Behav 2, 67–79 (2018). https://doi.org/10.1038/s41562-017-0249-4

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