Structure, function, and cortical representation of the rat submandibular whisker trident
Wallace, Michael L.
Chen, Christopher H.
MetadataShow full item record
Although the neurobiology of rodent facial whiskers has been studied intensively, little is known about sensing in other vibrissae. Here we describe the under-investigated submandibular “whisker trident” on the rat's chin. In this three-whisker array, a unique unpaired midline whisker is laterally flanked by two slightly shorter whiskers. All three whiskers point to the ground and are curved backwards. Unlike other whiskers, the trident is not located on an exposed body part. Trident vibrissae are not whisked and do not touch anything over long stretches of time. However, trident whiskers engage in sustained ground contact during head-down running while the animal is exploring or foraging. In biomechanical experiments, trident whiskers follow caudal ground movement more smoothly than facial whiskers. Remarkably, deflection angles decrease with increasing ground velocity. We identified one putative trident barrel in the left somatosensory cortex and two barrels in the right somatosensory cortex. The elongated putative trident-midline barrel is the longest and largest whisker barrel, suggesting that the midline trident whisker is of great functional significance. Cortical postsynaptic air-puff responses in the trident representation show much less temporal precision than facial whisker responses. Trident whiskers do not provide as much high-resolution information about object contacts as facial whiskers. Instead, our observations suggest an idiothetic function: their biomechanics allow trident whiskers to derive continuous measurements about ego motion from ground contacts. The midline position offers unique advantages in sensing heading direction in a laterally symmetric manner. The changes in trident deflection angle with velocity suggest that trident whiskers might function as a tactile speedometer.
© The Author(s), 2013. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Journal of Neuroscience 33 (2013): 4815-4824, doi:10.1523/JNEUROSCI.4770-12.2013.
The following license files are associated with this item:
Except where otherwise noted, this item's license is described as Attribution-NonCommercial-ShareAlike 3.0 Unported
Showing items related by title, author, creator and subject.
Murawski, Steven A.; Steele, John H.; Taylor, Phillip; Fogarty, Michael J.; Sissenwine, Michael P.; Ford, Michael; Suchman, Cynthia (Oxford University Press, 2009-08-30)Effective marine ecosystem-based management (EBM) requires understanding the key processes and relationships controlling the aspects of biodiversity, productivity, and resilience to perturbations. Unfortunately, the scales, ...
Quantity, composition, and source of sediment collected in sediment traps along the fringing coral reef off Molokai, Hawaii Bothner, Michael H.; Reynolds, Richard L.; Casso, Michael A.; Storlazzi, Curt D.; Field, Michael E. (Elsevier B.V., 2006-03-20)Sediment traps were used to evaluate the frequency, cause, and relative intensity of sediment mobility/resuspension along the fringing coral reef off southern Molokai (February 2000–May 2002). Two storms with high rainfall, ...
Live-cell imaging RNAi screen identifies PP2A–B55α and importin-β1 as key mitotic exit regulators in human cells Schmitz, Michael H. A.; Held, Michael; Janssens, Veerle; Hutchins, James R. A.; Hudecz, Otto; Ivanova, Elitsa; Goris, Jozef; Trinkle-Mulcahy, Laura; Lamond, Angus I.; Poser, Ina; Hyman, Anthony A.; Mechtler, Karl; Peters, Jan-Michael; Gerlich, Daniel W. (2010-07)When vertebrate cells exit mitosis, they reorganize various cellular structures to build functional interphase cells1. This depends on Cdk1 inactivation and subsequent dephosphorylation of its substrates2-4. Members of ...