Poster #: 121
Topic: Speech and language (incl. deficits)
Wednesday, Sep 9, 2015
Stability of the MMN, P3a and LDN responses to auditory frequency change between two repeated measurements in typically developing 5- to 6-year-old children
1Child Language Research Center, University of Oulu, Oulu, Finland
2Department of Psychology, University of Jyväskylä, Jyväskylä, Finland
3Department of Otorhinolaryngology, Oulu University Hospital, Oulu, Finland
4Logopedics, University of Oulu, Oulu, Finland
The evidence for the auditory processing skills is usually based on only one event-related potential (ERP) measurement. Only a few studies have reported the changes of the ERPs in the repeated measurements. We studied whether mismatch negativity (MMN), P3a, and late discriminative negativity (LDN) to frequency change remain stable between two measurements in twelve 5- to 6-year-old typically developing Finnish-speaking children. The stimulus pairs with two sine tones were presented in a passive oddball/MMN paradigm. The standard stimulus (80%) was a tone pair with a 150 ms within-pair interval (WPI) and the deviant stimulus (20%) was similar but having a frequency change in the latter tone. The time between the measurements was 6 weeks.
In the first measurement, the frequency change generated a fronto-central negative response (N250/MMN) at about 370 ms and LDN-like response 640-680 ms after the deviancy. In the second measurement the N250/MMN response was quite stable compared to the first measurement although the enhancement of N250/MMN was seen at the central scalp area. Between the measurements the amplitude of the LDN-like response differed, especially at the central and mastoid scalp areas indexing the strong activation of the auditory cortex. Additionally, P3a (at about 460 ms after the deviancy) appeared in the second measurement reflecting the involuntary attention switching mechanisms. No correlation was found between N250/MMN and P3a nor LDN and P3a indexing the independent auditory mechanisms.