Anonymized source data files for figures in: Recurrent processes support a cascade of hierarchical decisions

Perception depends on a complex interplay between feedforward and
recurrent processing. Yet, while the former has been extensively
characterized, the computational organization of the latter remains
largely unknown. Here, we use magneto-encephalography to localize, track
and decode the feedforward and recurrent processes of reading, as elicited
by letters and digits whose level of ambiguity was parametrically
manipulated. We first confirm that a feedforward response propagates
through the ventral and dorsal pathways within the first 200 ms. The
subsequent activity is distributed across temporal, parietal and
prefrontal cortices, which sequentially generate five levels of
representations culminating in action-specific motor signals. Our decoding
analyses reveal that both the content and the timing of these brain
responses are best explained by a hierarchy of recurrent neural
assemblies, which both maintain and broadcast increasingly rich
representations. Together, these results show how recurrent processes
generate, over extended time periods, a cascade of decisions that
ultimately accounts for subjects' perceptual reports and reaction
times.