Deviance Detection and Encoding Acoustic Regularity in the Auditory Midbrain

Abstract

In the past, there was a rather corticocentric conception of the processing of relationships between sounds that used to mostly relegate the midbrain function to a mere relay. However, increasing neurophysiological evidence demonstrates that the midbrain is, in fact, playing a crucial role in encoding some sorts of regularities present in the flow of acoustic stimulation, adapting the neuronal response for processing efficiency. Midbrain neurons are capable of responding more rapidly and strongly when a new stimulus is not matching to a previously encoded regularity; a phenomenon referred to as deviance detection. This chapter discusses deviance detection evidence in the midbrain, mainly describing the characteristics and mechanisms of stimulus-specific adaptation (SSA), and closing with an interpretation from the standpoint of the predictive coding theory.