Serial attentional resource allocation during parallel feature value tracking
Abstract
The visual system has evolved the ability to track features like color and orientation in parallel. This property aligns with the specialization of processing these feature dimensions in the visual cortex. But what if we ask to track changing feature-values within the same feature dimension? Parallel tracking would then have to share the same cortical representation, which would set strong limitations on tracking performance. We address this question by measuring the precision of color representations when human observers track the color of two superimposed dot clouds that simultaneously change color along independent trajectories in color-space. We find (1) that tracking precision is highly imbalanced between streams. (2) Tracking precision changes over time by alternating between streams at a rate of ~1Hz. These observations suggest that, while parallel color tracking is possible, it is highly limited, essentially allowing for only one color-stream to be tracked with precision at a given time.
Data availability
All raw data, the analyses are based on as well as analysis scripts are available online via the OSF repository: https://osf.io/y3qst/?view_only=b481b43b8b1447f8b8ccbcb5aeec7eb0 DOI (10.17605/OSF.IO/Y3QST)
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (SFB1436/B05)
- Jens-Max Hopf
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: All experiments were approved by the ethics-commission of the Otto-von-Guericke University (no. 141/20). All participants gave written informed consent and consent to publish prior to their participation.
Copyright
© 2023, Merkel 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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Further reading
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