Testing sensory evidence against mnemonic templates

Abstract
Article and author information
Metrics

Abstract

Most perceptual decisions require comparisons between current input and an internal template. Classic studies propose that templates are encoded in sustained activity of sensory neurons. However, stimulus encoding is itself dynamic, tracing a complex trajectory through activity space. Which part of this trajectory is pre-activated to reflect the template? Here we recorded magneto- and electroencephalography during a visual target-detection task, and used pattern analyses to decode template, stimulus, and decision-variable representation. Our findings ran counter to the dominant model of sustained pre-activation. Instead, template information emerged transiently around stimulus onset and quickly subsided. Cross-generalization between stimulus and template coding, indicating a shared neural representation, occurred only briefly. Our results are compatible with the proposal that template representation relies on a matched filter, transforming input into task-appropriate output. This proposal was consistent with a signed difference response at the perceptual decision stage, which can be explained by a simple neural model.

Article and author information

Author details

Nicholas Edward Myers

Department of Experimental Psychology, Oxford Centre for Human Brain Activity, University of Oxford, Oxford, United Kingdom

For correspondence
nicholas.myers@ohba.ox.ac.uk

Competing interests
The authors declare that no competing interests exist.
Gustavo Rohenkohl

Department of Experimental Psychology, Oxford Centre for Human Brain Activity, University of Oxford, Oxford, United Kingdom

Competing interests
The authors declare that no competing interests exist.
Valentin Wyart

Department of Experimental Psychology, Oxford Centre for Human Brain Activity, University of Oxford, Oxford, United Kingdom

Competing interests
The authors declare that no competing interests exist.
Mark W Woolrich

Department of Experimental Psychology, Oxford Centre for Human Brain Activity, University of Oxford, Oxford, United Kingdom

Competing interests
The authors declare that no competing interests exist.
Anna Christina Nobre

Department of Experimental Psychology, Oxford Centre for Human Brain Activity, University of Oxford, Oxford, United Kingdom

Competing interests
The authors declare that no competing interests exist.
Mark G Stokes

Department of Experimental Psychology, Oxford Centre for Human Brain Activity, University of Oxford, Oxford, United Kingdom

Competing interests
The authors declare that no competing interests exist.

Ethics

Human subjects: Ethical approval for methods and procedures was obtained from the Central University Research Ethics Committee of the University of Oxford. All participants provided written, informed consent.

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.