A time-stamp mechanism may provide temporal information necessary for egocentric to allocentric spatial transformations
- University of Ottawa, Canada
Abstract
Learning the spatial organization of the environment is essential for most animals' survival. This requires the animal to derive allocentric spatial information from egocentric sensory and motor experience. The neural mechanisms underlying this transformation are mostly unknown. We addressed this problem in electric fish, which can precisely navigate in complete darkness and whose brain circuitry is relatively simple. We conducted the first neural recordings in the preglomerular complex, the thalamic region exclusively connecting the optic tectum with the spatial learning circuits in the dorsolateral pallium. While tectal topographic information was mostly eliminated in preglomerular neurons, the time-intervals between object encounters were precisely encoded. We show that this reliable temporal information, combined with a speed signal, can permit accurate estimation of the distance between encounters, a necessary component of path-integration that enables computing allocentric spatial relations. Our results suggest that similar mechanisms are involved in sequential spatial learning in all vertebrates.
Data availability
Datasets and analysis files have been deposited in Columbia University's Academic Commons repository (https://doi.org/10.7916/D86Q3F7S).
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Data for: A time-stamp mechanism may provide temporal information necessary for egocentric to allocentric spatial transformationsColumbia Academic Commons, doi:10.7916/D86Q3F7S.
Article and author information
Author details
Funding
Natural Sciences and Engineering Research Council of Canada (121891-2009)
- André Longtin
Canadian Institutes of Health Research (49510)
- André Longtin
- Len Maler
Natural Sciences and Engineering Research Council of Canada (147489-2017)
- Len Maler
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 were approved by the University of Ottawa Animal Care and follow guidelines established by the Society for Neuroscience (approved protocol number:CMM-2897)
Copyright
© 2018, Wallach 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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A time-stamp mechanism may provide temporal information necessary for egocentric to allocentric spatial transformations
eLife 7:e36769.
https://doi.org/10.7554/eLife.36769
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