title: Principal component analyses and scalp distribution of the auditory P150-250 and N250-550 to speech contrasts in Mexican and American infants.
abstract: We report a Principal Component Analysis (PCA) and the scalp distribution of the normalized peak amplitude values for speech-related auditory Event-related Potentials (ERP) P150-250 and N250-550 in 7-, 11-, and 20-month-old American infants learning English and in 10-13-month-old Mexican infants learning Spanish. After assessing the infant auditory ERP P-N complex using PCA, we evaluated the topographic distribution of each of the discriminatory phases to native and non-native CV-syllabic contrasts used in Spanish and English. We found that the first two Principal Components for each contrast type across ages showing a maximization of differences between the P150-250 and the N250-550 waves, explain more than 70% of the variance. The scalp distributions of the P150-250 and N250-550 components also differed, the P150-250 showing a frontal and anterior temporal distribution, and the N250-550 a more posterior distribution. The older infants showed a broader distribution of responses, particularly for the N250-550. There were no differences in the topographies of the components between same-aged Mexican and American infants. We discuss the perceptual/linguistic functions that each component may reflect during development and across the two cultures.
authors.affiliation: Institute for Learning and Brain Sciences (I-LABS) and Department of Speech and Hearing Sciences, University of Washington, Seattle, WA 98195, USA. rivegaxi@u.washington.edu
authors.forename: Maritza
authors.initials: M
authors.lastname: Rivera-Gaxiola
authors.forename: Juan
authors.initials: J
authors.lastname: Silva-Pereyra
authors.forename: Lindsay
authors.initials: L
authors.lastname: Klarman
authors.forename: Adrian
authors.initials: A
authors.lastname: Garcia-Sierra
authors.forename: Lourdes
authors.initials: L
authors.lastname: Lara-Ayala
authors.forename: Cesar
authors.initials: C
authors.lastname: Cadena-Salazar
authors.forename: Patricia
authors.initials: P
authors.lastname: Kuhl
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D000367:Age Factors; D000569:Americas; D001307:Auditory Perception / Q000502:physiology; D001931:Brain Mapping; D003431:Cross-Cultural Comparison; D004569:Electroencephalography / Q000379:methods; D005006:Ethnicity; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007223:Infant; D007804:Language Development; D008297:Male; D008800:Mexico; D025341:Principal Component Analysis; D011930:Reaction Time / Q000502:physiology; D012535:Scalp; D013060:Speech / Q000502:physiology*