This is represented in the development of the ERAN and MMN. The ERAN cannot be verified in newborn babies, whereas the MMN can actually be demonstrated in [[fetus]]. In two-year-old children, the ERAN is very small, in five year old children a clear ERAN is found, but with a longer latency than in adults. With the age of 11 years children show an ERAN similar to ERANs in adults. Out of these observation the thesis can be built that the MMN is essential for the establishment and maintenance of representations of the acoustic environment and for processes of the auditory scene analysis. But only the ERAN is completely based on learning to build up a structural model, which is established with reference to representations of syntactic regularities already existing in a long-term memory format. Considering effects of [[training]] both the ERAN and the MMN can be modulated by training.
