Silent Expectations: Dynamic Causal Modeling of Cortical Prediction and Attention to Sounds That Weren't

Abstract

There is increasing evidence that human perception is realized by a hierarchy of neural processes in which predictions sent backward from higher levels result in prediction errors that are fed forward from lower levels, to update the current model of the environment. Moreover, the precision of prediction errors is thought to be modulated by attention. Much of this evidence comes from paradigms in which a stimulus differs from that predicted by the recent history of other stimuli (generating a so-called "mismatch response"). There is less evidence from situations where a prediction is not fulfilled by any sensory input (an "omission" response). This situation arguably provides a more direct measure of "top-down" predictions in the absence of confounding "bottom-up" input. We applied Dynamic Causal Modeling of evoked electromagnetic responses recorded by EEG and MEG to an auditory paradigm in which we factorially crossed the presence versus absence of "bottom-up" stimuli with the presence versus absence of "top-down" attention. Model comparison revealed that both mismatch and omission responses were mediated by increased forward and backward connections, differing primarily in the driving input. In both responses, modeling results suggested that the presence of attention selectively modulated backward "prediction" connections. Our results provide new model-driven evidence of the pure top-down prediction signal posited in theories of hierarchical perception, and highlight the role of attentional precision in strengthening this prediction.

Impairment in predictive processes during auditory mismatch negativity in ScZ: Evidence from event‐related fields

“…Importantly, MMNm‐responses were also expected to be reduced in omission trials. Findings by Wacongne et al [] and others [Chennu et al, ] showed that omission responses are similar in latency and topography to the MMN response elicited by deviant sequences. Finally, we expected the P300m elicited by a violation of global regularities to be reduced in ScZ.…”

Contributions of local speech encoding and functional connectivity to audio-visual speech perception

“…Predictions modulate auditory evoked responses in an area specific manner, involve both the ventral and dorsal pathways (Kandylaki et al, 2016; Sohoglu and Chait, 2016), and affect both feedforward and feedback connections (Auksztulewicz and Friston, 2016; Chennu et al, 2016). While an informative visual context facilitates the correction of predictions about expected speech using incoming multisensory evidence, we can only speculate about a direct link between the reported effects and predictive processes.…”

Evaluating the neurophysiological evidence for predictive processing as a model of perception

“…Thus, the particular neural populations and processing levels that are preferentially sampled by different recording techniques may be key to the study outcome. This may account for the fact that, in several instances, RS/ES effects that were observed with one noninvasive recording method were absent in another despite using otherwise identical paradigms 53,78,119 . This issue greatly complicates efforts to generate precise, empirically testable PP hypotheses and also reduces the scope for disconfirmatory results 42 .…”

“…This may account for the fact that, in several instances, RS/ES effects that were observed with one noninvasive recording method were absent in another despite using otherwise identical paradigms. 53,78,119 This issue greatly complicates efforts to generate precise, empirically testable PP hypotheses and also reduces the scope for disconfirmatory results. 42 In recognition of this point, researchers are increasingly seeking to verify the other hypotheses of PP by attempting to isolate mechanisms underlying the generation of predictions and hierarchical inference, and it is to this literature that we now turn our attention.…”