spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Wubbels, R. J.
Right arrow Articles by Schellart, NAM.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Wubbels, R. J.
Right arrow Articles by Schellart, NAM.

Journal of Experimental Biology, Vol 179, Issue 1 77-92, Copyright © 1993 by Company of Biologists

JOURNAL ARTICLES

RESPONSE PROPERTIES OF LATERAL LINE AND AUDITORY UNITS IN THE MEDULLA OBLONGATA OF THE RAINBOW TROUT (ONCORHYNCHUS MYKISS)

R. J. Wubbels, ABA. Kroese and NAM. Schellart

The objective of this study was to investigate the response properties of second-order lateral line and auditory neurones in the medulla oblongata of the rainbow trout. The frequency response of 20 medullary units was measured by recording single-unit spike activity in response to a mechanical stimulus provided by an oscillating membrane or by a small vibrating sphere. These 20 units were categorized, according to their frequency response properties, into two classes. Ten units responded to relatively low frequencies (<50 Hz) and showed a maximum in the frequency response between 70 and 120 Hz. The other units responded to higher frequencies, showing a maximum in the frequency response above 150 Hz. Significant differences between these two classes were also observed with respect to recording site, latency and sensitivity. It is concluded that these two classes of medullary units are lateral line units and auditory units, respectively. In the medulla, the input from the two mechanosensory systems appears to be mainly processed separately. The majority of mechanically sensitive units (95 %) showed a sustained, phase-locked response; 25 % displayed a transient response component, mostly in addition to a sustained response component. All units were spontaneously active, with a mean firing rate of 27 spikes s-1. Two units responded to a visual stimulus. No topographical representation of lateral line receptive fields was found in the caudal part of the medulla. The response characteristics of primary afferents reported in the literature differ from those of the medullary units of this study, so we conclude that the latter are higher-order units. Medullary lateral line units stimulated by the vibrating sphere appeared to be less sensitive than units stimulated by the vibrating membrane. The sensitivity of the units and the size of their receptive fields indicate that lateral line input converges in the medial nucleus.


This article has been cited by other articles:


Home page
 J. Exp. Biol.Home page
L. M. Palmer, M. Deffenbaugh, and A. F. Mensinger
Sensitivity of the anterior lateral line to natural stimuli in the oyster toadfish, Opsanus tau (Linnaeus)
J. Exp. Biol., September 15, 2005; 208(18): 3441 - 3450.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
R. J. Wubbels and N.A.M. Schellart
Neuronal Encoding of Sound Direction in the Auditory Midbrain of the Rainbow Trout
J Neurophysiol, June 1, 1997; 77(6): 3060 - 3074.
[Abstract] [Full Text] [PDF]


© The Company of Biologists Ltd 1993