Poster #15 - Comparing the auditory detection capacity between preschoolers and first-graders using Multi-feature MMN paradigm

• In Event: 3-159 - Poster Session 12
  In Poster Session: PS 12 Section - Biological Processes: Neuroscience and Genetics

Integrative Statement

The mismatch negativity (MMN) is elicited by any discriminable change in auditory stimulation irrespective of perceptual attention (Näätanen et al., 1978, 2001). MMN has been used as a tool of clinical research because of its highly association with dyslexia (Baldeweg et al., 1999), language impairment and reading problems (Sharma, 2007). However, so far no study has particularly examined the MMN for preschoolers and how this auditory event-related potential was developed as preschoolers transited into formal schooling. We have two aims for the current proposal: (a) contributing to a normative database of the MMN in preschool age population in China； (b) examining the developmental pattern of MMN after preschoolers transmitted into the formal school.
Two groups of participants (19 preschoolers and 17 first-grade elementary children) were recruited and all 19 preschoolers (10 male, mean age=6.3, SD=.13) were about to enter into first grade right before participated in our study. Multi-feature MMN paradigm was adopted from Näätänen et al (2004). The standard was a 500-Hz 100ms harmonically rich 3-partial sound. Deviants existed in five sound features: (1) duration deviants (65ms), (2) frequency deviants (±10%), (3) intensity deviants (±10 dB louder or softer), (4) sound location deviants (90°to the left or right), and (5) novel deviants (machine-like sounds, animal calls, or noises). The sounds were presented in a pseudorandom sequence so that the standard (50%) and one of the deviant tones (each 10%) occurred in alternating order with a stimulus onset asynchrony of 500ms. The stimuli were presented via headphones while the participants were watching a silenced movie. The duration of the paradigm was approximately 10 min.
We quantified MMN waveforms by subtracting ERPs of standard stimuli from those elicited by deviant stimuli. As MMN were distributed over fronto-central scalp locations (Näätänen & Alho,1995), we performed statistical analyses on 10 electrodes providing coverage of frontal-central scalp and the FCz channel was chosen for the statistical analysis (Näätänen et al., 2004). One-tailed t tests were conducted to determine MMN mean amplitudes significantly differed from zero in first-graders (t=2.864; p=0.010) except for the preschoolers (t=-1.140; not significant). Two-way analysis of variance (ANOVA) with repeated measures were conducted to test the effects of groups (2 levels: preschoolers and first-graders) and frontal-central scalp. In all conditions, deviants elicited MMNs that peaked around 200 ms from stimulus onset (Fig. 1). MMN amplitude differed between the groups (main effect of groups; F=7.012; p=0.012, η=0.171) which was larger in first-graders than in preschoolers.
The current study investigated the development of general sound feature processing between preschoolers and first-graders by recording MMN profiles in the Multi-feature paradigm to changes in various general sound dimensions. By the first-graders, they showed heightened sensitivity to changes in all deviants as indicated by their enhanced MMNs to changes in these dimensions. Thus, the current results converge with the literature highlighting the role of before and after school-age period in shaping brain development and extend previous findings to the processing of several general auditory dimensions that have remained unexplored in children thus far.

Authors

• Shuting Li, Beijing Normal University
  Presenting Author

• Qinxin Shi, Texas A&M University
  Non-Presenting Author

• Yingying Nie, Beijing Normal University
  Non-Presenting Author

• Cuicui Wang, Beijing Normal University
  Non-Presenting Author

• Sha Tao, Beijing Normal University
  Non-Presenting Author

• Steven Woltering, Texas A&M University
  Non-Presenting Author