title: The decline of cross-species intersensory perception in human infants: underlying mechanisms and its developmental persistence.
abstract: The current study investigated the mechanisms underlying the developmental decline in cross-species intersensory matching first reported by Lewkowicz and Ghazanfar [Lewkowicz, D.J., & Ghazanfar, A.A., (2006). The decline of cross-species intersensory perception in human infants. Proc. Natl. Acad. Sci. U. S. A. 103(17), 6771-6774] and whether the decline persists into later development. Experiment 1 investigated whether infants can match monkey vocalizations to asynchronously presented faces and found that neither 4-6 nor 8-10 month-old infants did. Experiment 1 also assessed whether a visual processing deficit may account for the developmental decline in cross-species matching and indicated that it does not because both age groups discriminated silent monkey calls. Experiment 2 investigated whether an auditory processing deficit may account for the decline and indicated that it does not because 8-10 month-old infants discriminated the acoustic versions of the calls. Finally, Experiment 3 asked whether the developmental decline persists into later development by testing cross-species intersensory matching in 12- and 18-month-old infants and showed that it does because neither age group made intersensory matches. Together, these results bolster prior evidence of a decline in cross-species intersensory integration in early human development and shed new light on the mechanisms underlying it.
authors.affiliation: Department of Psychology, Florida Atlantic University, 777 Glades Rd., Boca Raton, FL 33431, USA. lewkowic@fau.edu
authors.forename: David J
authors.initials: DJ
authors.lastname: Lewkowicz
authors.forename: Ryan
authors.initials: R
authors.lastname: Sowinski
authors.forename: Silvia
authors.initials: S
authors.lastname: Place
mesh_terms: D000818:Animals; D001307:Auditory Perception / Q000502:physiology*; D001921:Brain / Q000254:growth & development / Q000502:physiology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D014796:Visual Perception / Q000502:physiology*; D014828:Vocalization, Animal