Micromotional studies of utricular and canal afferents

final technical report 01/01/87 to 12/31/89

Publisher: University of California, Publisher: National Aeronautics and Space Administration, Publisher: National Technical Information Service, distributor in Berkeley, Calif, [Washington, DC, Springfield, Va

Written in English
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Subjects:

  • Space medicine.,
  • Reduced gravity environments.

Edition Notes

StatementEdwin R. Lewis, principal investigator.
Series[NASA contractor report] -- NASA-CR 192703., NASA contractor report -- NASA CR-192703.
ContributionsUnited States. National Aeronautics and Space Administration.
The Physical Object
FormatMicroform
Pagination1 v.
ID Numbers
Open LibraryOL14703872M

The innervation patterns of vestibular saccular afferents were quantitatively investigated in pigeons using biotinylated dextran amine as a neural tracer and three-dimensional computer reconstructi. B: 2nd-order neurons (n = 65) with converging inputs from utricular and canal nerve afferents were subdivided into 2nd-order utricular + horizontal canal (2°UT + HC), 2nd-order UT + anterior vertical canal (2°UT + AC), and 2nd-order UT + posterior vertical canal (2°UT + PC) neurons. Numbers of neurons are indicated in parentheses; mult. 1. Extracellular recording techniques were used in the chinchilla to study the discharge properties of utricular afferents, including their discharge regularity, background discharge, and responses to both externally applied galvanic currents and centrifugal forces. Studies suggesting the dangers of root canal started over one hundred years ago, and Dr. Price was one of the first dentists to show the link between root canal and various diseases. He extensively traveled and researched the importance of healthy diets and dental health in many populations all around the world.

For example, afferents projecting from extrastriolar and striolar utricular regions exhibit heterogeneity in their dynamic response characteristics (Eatock and Songer ), whereby the low-pass characteristics of extrastriolar afferents enable them to signal steady-state changes in head orientation relative to Earth gravity (Fernández and.   Resting discharge and response dynamics of horizontal semicircular canal afferent of the toadfish, Opsanus tau. J. Neurosci. Boyle, R., J. P. Carey, and S. M. Highstein. Morphological correlates of response dynamics and efferent stimulation in horizontal semicircular canal afferents of the toadfish, Opsanus tau. The Canal-Only central neurons encoded head rotation in canal afferent coordinates, exhibited no orthogonal canal convergence and were characterized by significantly higher sensitivities to rotation as compared to canal afferents. Another fourth of the neurons modulated their firing rates during translation (Otolith-Only cells). In this study, utricular stimulation in healthy subjects provoked symptoms of derealization similar to those observed during semicircular canal stimulation by caloric test and those reported by patients with peripheral vestibular disease, with no influence of the general characteristics of the subjects [14, 18, 19, 27]. The results consistency.

Imagawa M, Isu N, Sasaki M, Endo K, Ikegami H, and Uchino Y. Axonal projections of utricular afferents to the vestibular nuclei and the abducens nucleus in cats. Neurosci Lett , Crossref PubMed ISI Google Scholar; Imagawa M, Graf W, Sato H, Suwa H, Isu N, Izumi R, and Uchino Y. Morphology of single afferents of the saccular. At 0° roll, the average response has a peak-to-trough amplitude of ° and is symmetric about a downward eye position of °. The proposed Dual Otolith Model (DOM), based on a combination of utricular and saccular inputs, provided excellent fits to the present data (R2 =) and to the data of previous studies (R2 = to A Micro CT study of the mesiobuccal root canal morphology of the maxillary first molar tooth. International Endodontic Jour –, Abstract. Aim To observe the morphology of the root canal system of the maxillary first molar mesiobuccal root using micro computed tomography and compare it to current canal classifications. Then based on the studies of Wit et al. () who showed that fenestration of a semi-circular canal in pigeons led to increased magnitude of an auditory evoked potential (after surgical removal of the ductus cochlearis), Ribaric et al. (a&b) introduced a fenestration in the horizontal semicircular canal in profoundly deaf patients with.

Micromotional studies of utricular and canal afferents Download PDF EPUB FB2

Get this from a library. Micromotional studies of utricular and canal afferents: final technical report 01/01/87 to 12/31/ [Edwin R Lewis; United States.

National Aeronautics and Space Administration.]. Relation to Previous Work on Utricular Afferents. Utricular afferent terminal morphology has been quantified in chinchilla (Fernandez et al.

; Goldberg et al. b), bullfrog (Baird and Schuff ), pigeon (Si et al. ), and turtle (present results). One striking difference between these species is in the presence and distribution of Cited by:   Overview. Since canal afferents encode angular head velocity, electrical stimulation of the right posterior canal should provide the brain with information about the head’s angular velocity that is qualitatively similar to the canal input produced by an actual head rotation about the sensitive axis of the right posterior canal (except for the absence of modulation in the paired left anterior Cited by:   Objective: Eye movements evoked by otolith organ are not well-investigated compare with canal related eye movements due to the technical difficulties.

We try to solve this problem by means of our methods. Methods: Eye movements evoked by selective utricular (UT) nerve stimulation were investigated using both electrooculography (EOG) and video recording in decerebrated cats in the Cited by: mals, utricular afferents were predominantly labeled with in- jections sites located in the lateral portions of the SVN (n ⫽ 4) and lateral vestibular nucleus (LVN; n ⫽ 5).

In the present study, we observed axon collaterals in the reticular formation near the abducens nucleus and the spinal trigeminal nucleus. Utricular afferents also project to the area adjacent to the abducens nucleus 7, 10, 13, 14, while canal afferents typically give off collaterals in the direction of the cerebellum.

Thus, there is a clear. ELSEVIER Neuroscience Letters () NHRgscIDIC[ IHTEIIS Axonal projections of utricular afferents to the vestibular nuclei and the abducens nucleus in cats Midori Imagawaa, Naoki Isub, Mitsuyoshi Sasakia, Kenji Endo Hitoshi Ikegamic, Yoshio Uchinoa,* aDepartment of Physiology, Tokyo Medical College, Shinjuku, Shinjuku-ku, TokyoJapan bDepartment of.

While some studies found that sound activated both the semicircular canal afferents and the otolith organ afferents (Young et al.

; Carey et al. ; Zhu et al. a,b), others reported that sound primarily activated the saccular afferents (Murofushi et al. ; Murofushi and Curthoys ; Curthoys et al. ) and utricular afferents. One study of the frequency tuning of the human oVEMP response to BCV reported an enhanced oVEMP amplitude in response to Hz BCV stimulation compared to higher frequencies (Todd et al., ) and it was proposed that this may be due to irregular utricular afferents showing an enhanced response to Hz (a utricular “low frequency tuning.

Kevetter GA, Perachio A () Distribution of vestibular afferents that innervate the sacculus and posterior canal in the gerbil. J Comp Neurol – PubMed CrossRef Google Scholar Kleinschmidt HJ, Collewijn H () A search for habituation of vestibulo-ocular reactions to rotatory and linear sinusoidal accelerations in the rabbit.

The result is a comprehensive discussion of the main mechanisms of the labyrinth: the transduction pro­ cess at the receptor level, in the semicircular canals, and in the utricular and saccular maculae; the information transfer through neuronal pathways to the nuclei and the cerebellum; and the general organization of the system.

In the present study, we report the sensitivity of utricular afferents to sinusoidal translational motion in the horizontal plane. The head orientation was altered relative to the direction of. Relation to Previous Work on Utricular Afferents.

Utricular afferent terminal morphology has been quantified in chinchilla (Fernandez et al. ; Goldberg et al. b), bullfrog (Baird and Schuff ), pigeon (Si et al. ), and turtle (present results). One striking difference between these species is in the presence and distribution of.

The main objective of this study was to determine whether bone-conducted vibration (BCV) is equally effective in activating both semicircular canal and otolith afferents in the guinea pig or.

The classification of pigeon utricular afferents into calyx, dimorph, and bouton innervation patterns was based on the descriptions provided from previous studies of both utricle and semicircular canal afferents (Fernandez ; Fernandez et al. ,; Schessel et al. In the canal's cristae, previous studies reported that different classes of afferents are topographically organized in three concentric zones based on their morphophysiologic characteristics (Baird et al.

; Fernández et al.; Lysakowski et al. ; Haque et al. ): a scheme generally similar to that in otolith maculae. Shawn D Newlands's 54 research works with 1, citations and 1, reads, including: Convergence of Linear Acceleration and Yaw Rotation Signals on non-Eye Movement Neurons in the Vestibular.

The results of our study suggest that oVEMP induced by either ACS or BCV appears to depend on integrity of the superior vestibular nerve, possibly due to the utricular afferents travelling in it. Books. An illustration of two cells of a film strip. Video. An illustration of an audio speaker.

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Keskin, A micro‐computed tomographic study of band‐shaped root canal isthmuses, having their floor in the apical third of mesial roots of mandibular first molars, International Endodontic Journal, /iej, 51, 2, (), (). The model predicts that the net signal arising from vectorial summation of all semicircular canal afferents is equivalent to head rotation about a mid-sagittal axis.

Specifically, the axis is directed backwards and upwards by 18 deg above the line joining the lower orbital margin and the external auditory meatus (Fig. 1 A). However, such controversies have been overcome by basic neurophysiological studies and clinical studies.

Above all, sound sensit- ity of the saccular afferents shown in cats and guinea pigs with single-unit recording methods became the main supporting evidence. Nowadays, VEMP is one of the routine clinical tests for balance disorder. The major questions here are whether both the otolith and semicircular canal neurons are equally affected and whether both the utricular and saccular afferents are activated by both ACS and BCV.

Extracellular single neuron recording of primary vestibular afferents shows that it is almost exclusively otolith afferents with irregular resting. Recently a renewed interest has developed in the question of what constitutes the physiologic magnitude and bending mode of motion of the semicircular canal cupula.

InOman and Young (26) theoretically estimated that, regardless of bending mode, the motion of the middle of thehuman cupula ought to be limited to about 3 μm for maximal.

Perachio AA, Correia MJ () Responses of semicircular canal and otolith afferents to small angle static head tilts in the gerbil. Brain Res – PubMed Google Scholar Perachio AA, Kevetter GA () Identification of vestibular efferent neurons in the gerbil: histochemical and retrograde labelling.

Prior studies have, however, compared the resting rates and steady state (i.e., static) responses of utricular and saccular afferents evoked by the application of static tilts (Fernandez and Goldberg a; Fernandez et al.

; Tomko et al. In gerbils, the descending branch of the utricular, horizontal, and anterior canal afferents have medially directed collaterals, some towards the MVe.

Saccular afferents also have laterally directed collaterals ensuring coverage of the entire nucleus (Newlands and Perachio, ). Although relatively sparse, horizontal canal terminals are more.

Analysis of Horizontal Canal Afferent Dynamics Using White Noise and Sinusoids in the Barbiturate Anesthetized Cat.- The Response of Primary Semicircular Canal Neurons to Angular Accelerations of Varying Magnitude.- Dynamic Properties from Utricular Afferents.- 4 Visual-Vestibular Interactions.

Biotinylated dextran amine (BDA) was used to retrogradely label afferents innervating the utricular macula in adult pigeons. The pigeon utriclar macula consists of a large rectangular-shaped neuroe. The vestibular system is the system of balance and equilibrium.

It consists of five distinct sensory organs: three semicircular canals, which are sensitive to angular accelerations (head rotations), and two otoliths, which are sensitive to linear accelerations (e.g., motion in a vehicle or an elevator).

The utricular macula is oriented in approximately the same plane as the lateral (horizontal) semicircular canal (Lindeman, ), tilted rostrally upward 30° with respect to Reid's baseline (a line from the external auditory meatus to the inferior margin of the orbit; Corvera, Hallpike, & Schuster, ).It is a utricular reflex of the extraocular muscles.

Figure 1b. The surface response consists of a series of waves, starting with a negative potential at 10 ms (n10). The ocular VEMP, a similar reflex recorded from the extraocular muscles (see Figure 1a and 1b), was described in and now provides us with a new test of utricular function.large majority of regular firing and semicircular canal afferents cannot be activated with non‐traumatic sounds (9,10,12‐14).

potentially due to its close proximity to the stapes footplate, although some utricular afferents respond to ACS as well (8‐10,15‐17). stimulation and discovered a vestibular reflex during their studies.