Deviance Detection Based on Regularity Encoding Al

Authors: Carles Escera Sumie Leung Sabine Grimm

Publish Date: 2013/11/12

Volume: 27, Issue: 4, Pages: 527-538

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Abstract

Detection of changes in the acoustic environment is critical for survival as it prevents missing potentially relevant events outside the focus of attention In humans deviance detection based on acoustic regularity encoding has been associated with a brain response derived from the human EEG the mismatch negativity MMN auditory evoked potential peaking at about 100–200 ms from deviance onset By its long latency and cerebral generators the cortical nature of both the processes of regularity encoding and deviance detection has been assumed Yet intracellular extracellular singleunit and localfield potential recordings in rats and cats have shown much earlier circa 20–30 ms and hierarchically lower primary auditory cortex medial geniculate body inferior colliculus deviancerelated responses Here we review the recent evidence obtained with the complex auditory brainstem response cABR the middle latency response MLR and magnetoencephalography MEG demonstrating that human auditory deviance detection based on regularity encoding—rather than on refractoriness—occurs at latencies and in neural networks comparable to those revealed in animals Specifically encoding of simple acousticfeature regularities and detection of corresponding deviance such as an infrequent change in frequency or location occur in the latency range of the MLR in separate auditory cortical regions from those generating the MMN and even at the level of human auditory brainstem In contrast violations of more complex regularities such as those defined by the alternation of two different tones or by feature conjunctions ie frequency and location fail to elicit MLR correlates but elicit sizable MMNs Altogether these findings support the emerging view that deviance detection is a basic principle of the functional organization of the auditory system and that regularity encoding and deviance detection is organized in ascending levels of complexity along the auditory pathway expanding from the brainstem up to higherorder areas of the cerebral cortexThis work was supported by the Spanish Ministry of Economy and Knowledge Project PSI201237174 Programa EuroinvestigaciónEUI200904086 awarded to the ERANETNEURON Project PANS and ConsoliderIngenio 2010 program CDS200700012 Funds were also received from a grant from the Catalan Government SGR200911 and the ICREA Academia Distinguished Professorship awarded to Carles Escera

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