The conference is in English.
The mismatch negativity (MMN) is an electrical response in the brain caused by any change in a sound or sound pattern from the moment the memory keeps track of previous stimuli. When the change stimulus is introduced in a lower magnitude, then the mismatch negativity is attenuated in amplitude, until it disappears completely at the discrimination threshold.
Consequently, mismatch negativity provides an objective index of accuracy in determining all the different auditory characteristics in a subject or patient, such as frequency, loudness or even complex sound stimuli like different voice sounds.
In addition, improvements through training of different types of auditory discrimination abilities are highlighted through a greater amplitude of mismatch negativity. Such changes occur, for example, when an individual is exposed to a certain linguistic environment (e.g., when Finnish children enter a French crèche), when a newborn is exposed to his or her mother tongue, or when an adult studies a foreign language.
Discordance negativity can also be used as an index of the duration of sensory memory with regard to hearing. This information shows that the duration of auditory memory is around 10 seconds in healthy young adults, but shortens with age, becoming extremely short in patients showing degenerative brain disorders such as Alzheimer's disease.
In conclusion, studies on the subject taken as a whole suggest that mismatch negativity offers a unique index of general brain plasticity.
