Ultra-Rapid serial visual presentation reveals dynamics of feedforward and feedback processes in the ventral visual pathway

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Abstract

Human visual recognition activates a dense network of overlapping feedforward and recurrent neuronal processes, making it hard to disentangle processing in the feedforward from the feedback direction. Here, we used ultra-rapid serial visual presentation to suppress sustained activity that blurs the boundaries of processing steps, enabling us to resolve two distinct stages of processing with MEG multivariate pattern classification. The first processing stage was the rapid activation cascade of the bottom-up sweep, which terminated early as visual stimuli were presented at progressively faster rates. The second stage was the emergence of categorical information with peak latency that shifted later in time with progressively faster stimulus presentations, indexing time-consuming recurrent processing. Using MEG-fMRI fusion with representational similarity, we localized recurrent signals in early visual cortex. Together, our findings segregated an initial bottom-up sweep from subsequent feedback processing, and revealed the neural signature of increased recurrent processing demands for challenging viewing conditions.

Data availability

All data generated or analysed during this study to support the main findings are included in the manuscript and supporting files. Source data files have been provided for Figures 2, 3 and 5.

Article and author information

Author details

Yalda Mohsenzadeh

McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, United States

Competing interests
The authors declare that no competing interests exist.

"This ORCID iD identifies the author of this article:" 0000-0001-8525-957X
Sheng Qin

McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, United States

Competing interests
The authors declare that no competing interests exist.
Radoslaw M Cichy

Education and Psychology, Free University of Berlin, Berlin, Germany

Competing interests
The authors declare that no competing interests exist.
Dimitrios Pantazis

McGovern Institute for Brain Research, Massachusetts Institute of Technology, Cambridge, United States

For correspondence
pantazis@mit.edu

Competing interests
The authors declare that no competing interests exist.

"This ORCID iD identifies the author of this article:" 0000-0001-8246-8878

Funding

McGovern Institute (Neurotechnology Program)

Dimitrios Pantazis

Emmy Noether Award (CI241/1-1)

Radoslaw M Cichy

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Human subjects: The study was approved by the Institutional Review Board of the Massachusetts Institute of Technology and followed the principles of the Declaration of Helsinki. All subjects signed an informed consent form and were compensated for their participation.

Copyright

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.