Neural activity in a hippocampus-like region of the teleost pallium is associated with active sensing and navigation
Abstract
Most vertebrates use active sensing strategies for perception, cognition and control of motor activity. These strategies include directed body/sensor movements or increases in discrete sensory sampling events. The weakly electric fish, Gymnotus sp., uses its active electric sense during navigation in the dark. Electric organ discharge rate undergoes transient increases during navigation to increase electrosensory sampling. Gymnotus also use stereotyped backward swimming as an important form of active sensing that brings objects towards the electroreceptor dense fovea-like head region. We wirelessly recorded neural activity from the pallium of freely swimming Gymnotus. Spiking activity was sparse and occurred only during swimming. Notably, most units tended to fire during backward swims and their activity was on average coupled to increases in sensory sampling. Our results provide the first characterization of neural activity in a hippocampal (CA3)-like region of a teleost fish brain and connects it to active sensing of spatial environmental features.
Data availability
Data sets and analysis files have been deposited in University of Ottawa's Institutional repository.
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Neural activity in a hippocampus-like region of the teleost pallium is associated with active sensing and navigationUniversity of Ottawa's Institutional repository, 10.20381/RUOR38902.
Article and author information
Author details
Funding
Natural Sciences and Engineering Research Council of Canada (04336)
- Len Maler
Canadian Institutes of Health Research (153143)
- Len Maler
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Vatsala Thirumalai, National Centre for Biological Sciences, India
Ethics
Animal experimentation: All animal procedures were performed in accordance with the regulations of the animal care committee of the University of Ottawa, protocol number CMM-2897.
Version history
- Received: December 4, 2018
- Accepted: April 1, 2019
- Accepted Manuscript published: April 3, 2019 (version 1)
- Version of Record published: April 17, 2019 (version 2)
Copyright
© 2019, Fotowat 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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