Surface color and predictability determine contextual modulation of V1 firing and gamma oscillations
- Ernst Strüngmann Institute (ESI) for Neuroscience in Cooperation with Max Planck Society, Germany
- Max Planck Institute for Brain Research, Germany
Abstract
The integration of direct bottom-up inputs with contextual information is a core feature of neocortical circuits. In area V1, neurons may reduce their firing rates when their receptive field input can be predicted by spatial context. Gamma-synchronized (30-80Hz) firing may provide a complementary signal to rates, reflecting stronger synchronization between neuronal populations receiving mutually predictable inputs. We show that large uniform surfaces, which have high spatial predictability, strongly suppressed firing yet induced prominent gamma-synchronization in macaque V1, particularly when they were colored. Yet, chromatic mismatches between center and surround, breaking predictability, strongly reduced gamma-synchronization while increasing firing rates. Differences between responses to different colors, including strong gamma-responses to red, arose from stimulus adaptation to a full-screen background, suggesting prominent differences in adaptation between M- and L-cone signaling pathways. Thus, synchrony signaled whether RF inputs were predicted from spatial context, while firing rates increased when stimuli were unpredicted from context.
Data availability
As described in the Methods section, several datasets were acquired in this study. Datasets have been uploaded onto Dryad (https://doi.org/10.5061/dryad.4809qj4). Thse include individual sessions with each session preprocessed (downsampled, see Methods), epoched into trials with time, channel and condition information.
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Data from: Surface color and predictability determine contextual modulation of macaque V1 firing and gamma oscillationsDryad Digital Repository, doi:10.5061/dryad.4809qj4.
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (SPP 1665)
- Pascal Fries
European Commission (FP7-604102-HBP)
- Pascal Fries
Deutsche Forschungsgemeinschaft (FOR 1847)
- Pascal Fries
Deutsche Forschungsgemeinschaft (FR2557/5-1-CORNET)
- Pascal Fries
Deutsche Forschungsgemeinschaft (FR2557/6-1-NeuroTMR)
- Pascal Fries
Deutsche Forschungsgemeinschaft (Reinhart Kosselleck grant)
- Wolf Singer
National Institutes of Health (1U54MH091657-WU-Minn- Consortium-HCP)
- Pascal Fries
European Science Foundation (European Young Investigator Award)
- Pascal Fries
LOEWE (NeFF)
- Pascal Fries
European Commission (HEALTH-F2-2008-200728-BrainSynch)
- Pascal Fries
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All procedures complied with the German and European regulations for the protection of animals and were approved by the regional authority (Regierungspräsidium Darmstadt, F-149-1000/1005). All surgeries were performed under anesthesia and were followed by analgesic treatment post-operatively.
Copyright
© 2019, Peter et al.
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.
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Surface color and predictability determine contextual modulation of V1 firing and gamma oscillations
eLife 8:e42101.
https://doi.org/10.7554/eLife.42101
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