Please cite this article in press as: Rosa Salva, O., et al., Roots of a social brain: Developmental models of emerging animacy-detection mechanisms. Neurosci. Biobehav. Rev. (2015), http://dx.doi.org/10.1016/j.neubiorev.2014.12.015 ARTICLE IN PRESS G Model NBR-2104; No. of Pages 19 Neuroscience and Biobehavioral Reviews xxx (2015) xxx–xxx Contents lists available at ScienceDirect Neuroscience and Biobehavioral Reviews jou rn al h om epage: www.elsevier.com/locate/neubiorev Review Roots of a social brain: Developmental models of emerging animacy-detection mechanisms O. Rosa Salva, U. Mayer, G. Vallortigara * Center for Mind/Brain Sciences, University of Trento, Corso Bettini 31, 38068, Rovereto, Italy a r t i c l e i n f o Article history: Received 1 March 2014 Received in revised form 16 December 2014 Accepted 18 December 2014 Available online xxx Keywords: Social predispositions Animacy Domestic chick Gallus gallus Subcortical structures Optic tectum Superior colliculus Innate Biological motion Self-propulsion a b s t r a c t Here, we review evidence of unlearned predispositions to orient toward visual and auditory cues asso- ciated with the presence of animate creatures. We concentrate on studies on chicks of galliform species, whose behavioural preferences for social partners are analyzed in a comparative perspective with respect to the human developmental literature. The emerging nature of chicks’ social predispositions is discussed in relation to the underlying physiological mechanisms and to the role of genetic and environmental factors in their development. In the second part of the review, we summarize evidence on the neural substrate of the animacy detectors, again focusing on our animal model of election, the domestic chick. On the basis of a substantial amount of indirect evidence, subpallial structures, among which the optic tectum (homologous to the mammalian superior colliculus), seem to comprise the most probable candi- dates. We also discuss some preliminary evidence of different brain activity, measured by IEG expression, in chicks exposed to predisposed or a non-predisposed stimulus. © 2014 Elsevier Ltd. All rights reserved. Contents 1. Behavioural evidence of social predisposition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00 1.1. Visual predispositions for colours, shapes and configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00 1.2. Visual predispositions for different kinds of motion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00 1.3. Acoustical predispositions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00 2. Sensory stimulation and the emergence of predispositions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00 2.1. Developmental origins of the species-specific predispositions of galliform chicks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00 2.2. Developmental origins of the general predispositions for animacy of galliform chicks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00 3. Neuronal bases of social predispositions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00 3.1. The visual system of birds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00 3.2. Processing of innate predispositions in birds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00 4. Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 00 * Corresponding author. Tel.: +39 0464 808615. E-mail address: giorgio.vallortigara@unitn.it (G. Vallortigara). http://dx.doi.org/10.1016/j.neubiorev.2014.12.015 0149-7634/© 2014 Elsevier Ltd. All rights reserved.