The hemodynamic response to acoustically modified syllables in premature and full term newborn infants acquired by near infrared spectroscopy.

Abstract

This research assesses, in newborns, the hemodynamic response to acoustically modified syllables (pronounced in a prolonged manner), versus the response to unmodified syllables (pronounced at a normal rate). The aim was to assess which of these stimulation conditions produced better syllable discrimination in two groups of neonates: 13 preterm (mean gestational age 30 weeks, SD 3 weeks), and 13 full term newborns (mean age 38 weeks, SD 1 week). Syllable discrimination, in each condition, was assessed by using an oddball paradigm (equal syllable trials vs. different syllable trials). The statistical analysis was based on the comparison between the hemodynamic response [oxyHbO] obtained by Near Infrared Spectroscopy (NIRS) to different syllable trials vs. equal syllable trials, in each condition. The modified syllable condition was better in producing trial discrimination in both groups. The amplitude of the hemodynamic response to the different syllable trials was greater than the one to the equal syllable trials: for term infants, t = 2.59, p = 0.024, and for preterm t = 2.38, p = 0.035. This finding occurred in the left temporal lobe. These data suggest that the modified syllables facilitate processing of phonemes from birth. Key words: Preterm neonates, language acquisition, acoustically modified syllables, auditory temporal processing, Near Infrared Spectroscopy. RESPUESTA HEMODINÁMICA A SÍLABAS MODIFICADAS ACÚSTICAMENTE EN RECIÉN NACIDOS PREMATUROS Y A TÉRMINO ADQUIRIDA POR ESPECTROSCOPÍA DEL INFRARROJO CERCANO ResumenEsta investigación evalúa, en neonatos, la respuesta hemodinámica ante sílabas modificadas acústicamente (pronunciadas de manera prolongada) en comparación con la respuesta a sílabas no modificadas (pronunciadas a una velocidad normal). El objetivo fue evaluar cuál de estas condiciones de estimulación producía una mejor discriminación silábica en dos grupos de neonatos: 13 prematuros (edad gestacional promedio de 30 semanas, DE 3 semanas) y 13 nacidos a término (edad gestacional promedio de 38 semanas, DE 1 semana). La discriminación de sílabas, en cada condición, se evaluó mediante un paradigma oddball (ensayos con sílabas iguales vs. ensayos con sílaba diferente). El análisis estadístico se basó en la comparación de la Acta.colomb.psicol. 17 (2): 13-21, 2014 http://www.dx

Cerebral hemodynamic responses in preterm-born neonates to visual stimulation: classification according to subgroups and analysis of frontotemporal–occipital functional connectivity

“…This highlights once more the question of why we see such differences in the hemodynamic changes in our group of preterm-born neonates, and whether it will generally be possible to define a typical HR for different regions in the cortex of the developing brain. Previously published fNIRS studies investigating HRs of preterm-born neonates [35][36][37][38][39][40][41][42][43] did not perform a subgroup analysis. Instead, a group average was calculated.…”

“…8, performing the fNIRS measurement with an advanced multidistance measurement technique (SCMD) enables the determination of the hemodynamic changes inside the neonate's brain while minimizing possible influences from the extracerebral tissue compartment. Previous fNIRS studies in preterm-born neonates used single-distance 35,36,39,40,43 and multidistance 38,42,68 measurements. Owing to the fact that changes in scalp blood flow can interfere with fNIRS measurements, 17,69 the application of multidistance fNIRS measurements is warranted for fNIRS studies.…”