Expectation and attention in hierarchical auditory prediction

SRIVAS CHENNU; VALDAS NOREIKA; DAVID GUEORGUIEV; ALEJANDRO BLENKMANN; SILVIA KOCHEN; AGUSTÍN MARIANO IBÁÑEZ BARASSI; ADRIAN OWEN; TRISTAN BEKINSCHTEIN

JOURNAL OF NEUROSCIENCE

SOC NEUROSCIENCE

Lugar: Washington; Año: 2013 vol. 33 p. 11194 - 11205

0270-6474

Hierarchical predictive coding suggests that attention in humans emerges from increased precision in probabilistic inference, while expectation biases attention in favour of contextually anticipated stimuli. We test these notions within auditory perception by independently manipulating top-down expectation and attentional precision alongside bottom-up stimulus predictability. Our findings support an integrative interpretation of commonly observed electrophysiological signatures of neurodynamics, namely the MMN (Mismatch Negativity), P300 and CNV (Contingent Negative Variation), as manifestations along successive levels of predictive complexity. Early first-level processing indexed by the MMN was sensitive to stimulus predictability: here, attentional precision enhanced early responses, but explicit top-down expectation diminished it. This pattern was in contrast to later, second-level processing indexed by the P300: though sensitive to the degree of predictability, responses at this level were contingent on attentional engagement, and in fact sharpened by top-down expectation. At the highest level, the drift of the CNV was a fine grained marker of top-down expectation itself. Source reconstruction of high-density EEG, supported by intracranial recordings, implicated temporal and frontal regions differentially active at early and late levels. The cortical generators of the CNV suggested that it might be involved in facilitating the consolidation of context-salient stimuli into conscious perception. These results provide convergent empirical support to promising recent accounts of attention and expectation in predictive coding.