Broadband Signal Rather than Frequency-Specific Rhythms Underlies Prediction Error in the Primate Auditory Cortex

SummaryDetection of statistical irregularities, measured as a prediction error response, is fundamental to the perceptual monitoring of the environment. We studied whether prediction error response is generated by neural oscillations or asynchronous neuronal firing. Electrocorticography (ECoG) was carried out in three monkeys, who passively listened to the auditory roving oddball stimuli. Local field potentials (LFP) recorded over the auditory cortex underwent spectral principal component analysis, which decoupled broadband and rhythmic components of LFP signal. We found that broadband component generated prediction error response, whereas none of the rhythmic components encoded statistical irregularities of sounds. The broadband component displayed more stochastic, asymmetrical multifractal properties than the rhythmic components, which revealed more self-similar dynamics. We thus conclude that the prediction error response is encoded by asynchronous neuronal populations, defined by irregular dynamical states which, unlike oscillatory rhythms, appear to enable the neural representation of auditory prediction error response.