Cognitive control of heart rate in diving harbor porpoises
Abstract
Marine mammals have adapted to forage while holding their breath in a suite of aquatic habitats from shallow rivers to deep oceans. The key to tolerate such extensive apnea is the dive response, which comprises bradycardia and peripheral vasoconstriction. Although initially considered an all-or-nothing reflex [1] , numerous studies on freely diving marine mammals have revealed substantial dynamics of the dive response to meet the impending dive demands of depth, duration and exercise [2] . Such adjustments are not only autonomic responses, but are under acute cognitive control in pinnipeds [3] living amphibiously on land and in water. The fully aquatic cetaceans would similarly benefit from cognitive cardiovascular control; however, even though they have exercise-modulated diving bradycardia [2] and full voluntary control of their respiratory system to such extent that even mild anesthesia often leads to asphyxiation [4] , cognitive cardiovascular control has never been demonstrated for this large group of marine mammals. To address this, we tested the hypothesis that porpoises modulate bradycardia according to anticipated dive duration. Two harbor porpoises, instrumented with ECG recording tags, were trained to perform 20- and 80-second stationary dives, during which they adjusted bradycardia to the anticipated duration, demonstrating cognitive control of their dive response.
Citation
Elmegaard , S , Johnson , M , Madsen , P & McDonald , B 2016 , ' Cognitive control of heart rate in diving harbor porpoises ' , Current Biology , vol. 26 , no. 22 , pp. R1175-R1176 . https://doi.org/10.1016/j.cub.2016.10.020
Publication
Current Biology
Status
Peer reviewed
ISSN
0960-9822Type
Journal article
Rights
© 2016, Elsevier. This work has been made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at www.sciencedirect.com / http://dx.doi.org/10.1016/j.cub.2016.10.020
Description
M.J. was funded by the Marine Alliance for Science and Technology, Scotland, and by a Marie Curie Career Integration Grant.Collections
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