Response of vestibular neurons to head rotations in vertical planes. III. Response of vestibulocollic neurons to vestibular and neck stimulation

1990 ◽  
Vol 64 (6) ◽  
pp. 1695-1703 ◽  
Author(s):  
V. J. Wilson ◽  
Y. Yamagata ◽  
B. J. Yates ◽  
R. H. Schor ◽  
S. Nonaka
Keyword(s):  
The Body ◽  
Whole Body ◽  
Decerebrate Cat ◽  
Vestibular Neurons ◽  
Neuron Response ◽  
Antidromic Responses ◽  
Neck Rotation ◽  
Vector Orientation ◽  
Head Rotations

1. To compare the properties of the vestibulocollic reflex (VCR) with those of vestibular neurons projecting to the neck [vestibulocollic (VC) neurons], we have studied the behavior of the latter in the decerebrate cat. Neurons were identified by their antidromic responses to stimulation in C1-C2, but not C5. Responses to stimulation of vestibular and neck receptors were produced by rotation of the body and head in vertical planes. 2. We determined the plane of whole body (vestibular) or body with head counter-rotated (neck) rotation, which produced the maximal modulation of each neuron (response vector orientation). Neuron dynamics were then studied with sinusoidal (0.02–2 Hz) stimuli aligned with this orientation. 3. On the basis of dynamics and vector orientation, the neuron was assigned a vestibular input classification of otolith, vertical canal, otolith + canal, or spatial-temporal convergence (STC). 4. The properties of this sample of VC neurons are similar to those of a larger population of vestibular neurons whose projection was not identified. For example, the distributions of cells with different types of vestibular inputs were roughly the same; in particular, few cells showed STC responses. In addition, there was no evidence of significant convergence of like canals across the midline (e.g., right anterior + left anterior). 5. Also similar to the larger unidentified population, 80% of VC neurons tested for neck input received such an input. The neck and vestibular responses tended to be antagonistic; the vector orientations were usually opposite, and the response gains and phases similar.(ABSTRACT TRUNCATED AT 250 WORDS)

Responses of neurons of the cat central cervical nucleus to natural neck and vestibular stimulation

1996 ◽  
Vol 76 (4) ◽  
pp. 2786-2789 ◽  
Author(s):  
D. B. Thomson ◽  
N. Isu ◽  
V. J. Wilson
Keyword(s):  
Vestibular Nuclei ◽  
Vestibular Stimulation ◽  
Body Tilt ◽  
Whole Body ◽  
Vestibular Input ◽  
Preferred Direction ◽  
Central Cervical Nucleus ◽  
Neck Rotation ◽  
Vector Orientation ◽  
To Receive

1. The central cervical nucleus (CCN) is known to receive neck and vestibular input and to project to the contralateral cerebellum and vestibular nuclei. To investigate the processing of neck and vestibular input by cells in the CCN, we studied their responses to sinusoidal neck rotation and to whole-body tilt in vertical planes in decerebrate, paralyzed cats. CCN neurons were identified by antidromic stimulation with electrodes placed in or near the contralateral restiform body. 2. For every neuron, we first identified the preferred direction of neck rotation (response vector orientation), then studied the neuron's dynamics with rotations in a plane close to this direction at 0.05-1 Hz. 3. Responses of CCN neurons to neck rotation resembled those of previously studied neck spindle primary afferents in terms of their dynamics and nonlinear responses to stimuli of differing amplitudes. They also resembled the neck responses of Deiters' neurons studied in similar preparations. 4. The activity of two-thirds of CCN neurons also was modulated by natural vestibular stimulation. Orientation and dynamics of vestibular responses were characterized in the same way as neck responses. Labyrinthine input originated predominantly from the contralateral vertical canals, and there was no evidence of otolith input. Neck and vestibular inputs were always antagonistic, but the gain of the vestibular response was lower than that of the neck response at all frequencies studied. 5. The quantitative aspects of the interaction between neck and vestibular inputs can be expected to vary with the type of preparation and with stimulus parameters, and its functional significance remains to be investigated.

Response of Vestibular-Nerve Afferents to Active and Passive Rotations Under Normal Conditions and After Unilateral Labyrinthectomy

2007 ◽  
Vol 97 (2) ◽  
pp. 1503-1514 ◽  
Author(s):  
Soroush G. Sadeghi ◽  
Lloyd B. Minor ◽  
Kathleen E. Cullen
Keyword(s):  
Discharge Rate ◽  
Vestibular Nerve ◽  
The Body ◽  
Head Movements ◽  
Whole Body ◽  
Before And After ◽  
Unilateral Labyrinthectomy ◽  
Vestibular Nerve Afferents ◽  
Head Rotations

We investigated the possible contribution of signals carried by vestibular-nerve afferents to long-term processes of vestibular compensation after unilateral labyrinthectomy. Semicircular canal afferents were recorded from the contralesional nerve in three macaque monkeys before [horizontal (HC) = 67, anterior (AC) = 66, posterior (PC) = 50] and 1–12 mo after (HC = 192, AC = 86, PC = 57) lesion. Vestibular responses were evaluated using passive sinusoidal rotations with frequencies of 0.5–15 Hz (20–80°/s) and fast whole-body rotations reaching velocities of 500°/s. Sensitivities to nonvestibular inputs were tested by: 1) comparing responses during active and passive head movements, 2) rotating the body with the head held stationary to activate neck proprioceptors, and 3) encouraging head-restrained animals to attempt to make head movements that resulted in the production of neck torques of ≤2 Nm. Mean resting discharge rate before and after the lesion did not differ for the regular, D (dimorphic)-irregular, or C (calyx)-irregular afferents. In response to passive rotations, afferents showed no change in sensitivity and phase, inhibitory cutoff, and excitatory saturation after unilateral labyrinthectomy. Moreover, head sensitivities were similar during voluntary and passive head rotations and responses were not altered by neck proprioceptive or efference copy signals before or after the lesion. The only significant change was an increase in the proportion of C-irregular units postlesion, accompanied by a decrease in the proportion of regular afferents. Taken together, our findings show that changes in response properties of the vestibular afferent population are not likely to play a major role in the long-term changes associated with compensation after unilateral labyrinthectomy.

scholarly journals Ethnic Differences in the BMI-%BF Relationships between Young Japanese and Australian-Caucasian Males Living in Australia Using Dual-Energy X-ray Absorptiometry

2003 ◽  
Vol 15 (1_suppl) ◽  
pp. S27-S32 ◽  
Author(s):  
M Kagawa ◽  
D Kerr ◽  
C Binns
Keyword(s):  
Ethnic Differences ◽  
World Health Organisation ◽  
Dual Energy ◽  
The Body ◽  
World Health ◽  
Asia Pacific ◽  
Whole Body ◽  
X Ray ◽  
Total Body

The Body Mass Index (BMI) has been used worldwide as an indicator of fatness. However, the universal cut-off points by the World Health Organisation (WHO) classification may not be appropriate for every ethnic group when consider the relationship with their actual total body fatness (%BF). The application of population-specific classifications to assess BMI may be more relevant to public health. Ethnic differences in the BMI-%BF relationship between 45 Japanese and 42 Australian-Caucasian males were assessed using whole body dual-energy X-ray absorptiometry (DXA) scan and anthropometry using a standard protocol. Japanese males had significantly ( p<0.05) greater %BF at given BMI values than Australian males. When this is taken into account the newly proposed Asia-Pacific BMI classification of BMI >23 as overweight and >25 as obese may better assess the level of obesity that is associated increased health risks for this population. To clarify the current findings, further studies that compare the relationships across other Japanese populations are recommended.

scholarly journals HISTORICAL PRESPECTIVE OF TEMPERAMENT IN UNANI MEDICINE: A REVIEW

2020 ◽  
pp. 1-5
Author(s):  
Afroza Jan ◽  
Haider Ali Quraishi ◽  
Arsheed Iqbal
Keyword(s):  
Good Health ◽  
The Body ◽  
Whole Body ◽  
Unani Medicine ◽  
Bodily Fluids ◽  
Natural Remedies ◽  
The Right ◽  
Diet And Lifestyle ◽  
Geographical Locations

Unani Medicine or Tibb system is based on classification of humans personalities into four different mizaj based on dominance body fluids. The fundamentals of Unani medicine are mainly based upon the temperament (Mizaj) and Humours (Akhlat). It was described by various eminent Graeco-Arab physicians Jalinoos. Abu bakr Mohammad bin Zakaria Razi, Ali Ibne Abbas Majoosi , Rabban Tabri , Ibne Rushd and other eminent Unani scholar in their literatures.. According to them the specific temperament is present in every individual. In healing drugs as well as diseases are also classified according to the four humors. The four humors correspond to four bodily fluids ie blood (Dam), phlegm (Balgham), black bile (sauda) and yellow bile (safra). A typical diagnosis of a patient would take the balance of these humors into consideration, before giving any treatment. It is also very important to keep the temperament in mind while diagnosing a disease. The Mizaj (temperament) is a notion (concept) and a way by which physicians evaluate the deviation of the body or any of its organs from normal homeostasis in comparison to the patient’s population, race, and species. Merely, it is the appearance that Unani physicians use to tell whether the whole body or one of its organs has the right temperature and has the right amount of moisture. There is no absolute temperament, that is, there is not one universal temperament to which we compare the health of an individual. Moreover, there is not one temperament that is the best or the optimum for all types of geographical locations. The dominance of one or more humours in the body vitiates humour itself and causes disease. Temperament (Mizaj) is also importance in the treatment of diseases with natural remedies derived from Herbo-animo-mineral sources. It is also taken into consideration for identifying the most suitable diet and lifestyle for promoting good health.

Responses to head tilt in cat central vestibular neurons. I. Direction of maximum sensitivity

1984 ◽  
Vol 51 (1) ◽  
pp. 136-146 ◽  
Author(s):  
R. H. Schor ◽  
A. D. Miller ◽  
D. L. Tomko
Keyword(s):  
Vestibular Nucleus ◽  
Head Tilt ◽  
Semicircular Canals ◽  
Broad Distribution ◽  
Decerebrate Cat ◽  
Vestibular Neurons ◽  
Maximal Sensitivity ◽  
Vector Orientation ◽  
Roll Tilt ◽  
Response Vector

Responses to head tilt were recorded from vestibular neurons in and around the lateral vestibular nucleus (LVN) of the decerebrate cat. Each animal had all six semicircular canals rendered nonfunctional by a plugging procedure. Each cell was studied by slowly tilting the cat, using one or both of two paradigms. In the first method, sinusoidal tilts (0.05 or 0.1 Hz) were used to produce bidirectional stimuli in up to 12 pairs of directions, including left/right (roll tilt) and fore/aft (pitch). The second method imposed a constant 10 degree tilt; the direction of the tilt was rotated around the animal by an appropriate combination of roll and pitch motions. Neurons responded by maximally increasing their discharge frequency in a particular direction of head tilt from the horizontal. Each cell's response could be described by a vector in the animal's horizontal plane whose orientation is given by the direction of the most effective stimulus and whose length represents the neuron's maximal sensitivity to tilt. The two methods of stimulation yielded equivalent response vectors. Response vectors were obtained for 100 neurons. The distribution of vector directions for these vestibular neurons was not uniform; there was a conspicuous absence of neurons with fore/aft-directed vectors. The sensitivity of these cells (length of the response vector) ranged from 10 to 230 impulses X s-1 X g-1 (median 50). Neurons whose vectors lay in the ipsilateral half-plane (which would be excited by ear-down tilt) tended to be less sensitive than those with contralateral vectors. Neurons excited by ear-up tilt tended to be located ventrally in the LVN, while those excited by ear-down tilt were more evenly distributed. There was no other obvious correlation of vector orientation with the anatomical locus of the cell in the LVN. The directional selectivity of the responses of these neurons to head tilts are similar to those previously reported tin utricular afferents. The broad distribution of response vector orientations provides an appropriate substrate for vestibulospinal reflexes to a wide variety of head tilts.

Response of pontomedullary reticulospinal neurons to vestibular stimuli in vertical planes. Role in vertical vestibulospinal reflexes of the decerebrate cat

1992 ◽  
Vol 67 (3) ◽  
pp. 639-647 ◽  
Author(s):  
P. S. Bolton ◽  
T. Goto ◽  
R. H. Schor ◽  
V. J. Wilson ◽  
Y. Yamagata ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Decerebrate Cat ◽  
Reticulospinal Neurons ◽  
Neuron Response ◽  
Vestibulospinal Reflexes ◽  
Upper Cervical ◽  
Vector Orientation ◽  
Labyrinth Stimulation ◽  
Vestibulospinal Neurons ◽  
Response Vector

1. To investigate the neural substrate of vestibulospinal reflexes in decerebrate cats, we studied the responses of pontomedullary reticulospinal neurons to natural stimulation of the labyrinth in vertical planes. Our principal aim was to determine whether reticulospinal neurons that terminate in, or are likely to give off collaterals to, the upper cervical segments had properties similar to those of the vestibulocollic reflex (VCR). 2. Antidromic stimulation was used to determine whether the neurons projected to the neck, lower cervical, thoracic, or lumbar levels. Dynamics of the responses of spontaneously firing neurons were studied with sinusoidal stimuli delivered at 0.05-1 Hz and aligned to the plane of body rotation, that produced maximal modulation of the neuron (response vector orientation). Each neuron was assigned a vestibular input classification of otolith, vertical canal, otolith + canal, or spatial-temporal convergence (STC). 3. We found, in agreement with previous studies, that the largest fraction of pontomedullary reticulospinal neurons projected to the lumbar cord, and that only a small number ended in the neck segments. Neurons projecting to all levels of the spinal cord had similar responses to labyrinth stimulation. 4. Reticulospinal neurons that received only vertical canal inputs were rare (1 of 67 units). Most reticulospinal neurons (48%) received predominant otolith inputs, 18% received otolith + canal input, and only 9% had STC behavior. These data are in sharp contrast to the results of our previous studies of vestibulospinal neurons. A considerable portion of vestibulospinal neurons receives vertical canal input (38%), fewer receive predominantly otolith input (22%), whereas the proportion that have otolith + canal input or STC behavior is similar to our present reticulospinal data. 5. The response vector orientations of our reticulospinal neurons, particularly those with canal inputs (canal, otolith + canal, STC) were predominantly in the roll quadrants. There was no evidence of convergence of inputs from like canals across the midline (e.g., right anterior + left anterior). 6. Two characteristics of the VCR, STC behavior and bilateral input from symmetric vertical canals (in some muscles), cannot be accounted for by the reticulospinal neurons that we studied. Because these characteristics are also not seen in vestibulocollic neurons, they are likely to be the result of the appropriate convergence of vestibular signals in the spinal cord. 7. Pontomedullary reticulospinal neurons seem particularly well suited to play a role in gravity-dependent postural reflexes of neck and limbs.

A Simple and Inexpensive Clinical Whole Body Counter

1976 ◽  
Vol 15 (05) ◽  
pp. 248-253
Author(s):  
A. K. Basu ◽  
S. K. Guha ◽  
B. N. Tandon ◽  
M. M. Gupta ◽  
M. ML. Rehani
Keyword(s):  
The Body ◽  
Whole Body ◽  
Vitro Assay ◽  
Body Counter ◽  
Optimum Parameters ◽  
Whole Body Counter ◽  
Single Detector ◽  
Background Index ◽  
Iodide Crystal

SummaryThe conventional radioisotope scanner has been used as a whole body counter. The background index of the system is 10.9 counts per minute per ml of sodium iodide crystal. The sensitivity and derived sensitivity parameters have been evaluated and found to be suitable for clinical studies. The optimum parameters for a single detector at two positions above the lying subject have been obtained. It has been found that for the case of 131I measurement it is possible to assay a source located at any point in the body with coefficient of variation less than 5%. To add to the versatility, a fixed geometry for in-vitro counting of large samples has been obtained. The retention values obtained by the whole body counter have been found to correlate with those obtained by in-vitro assay of urine and stool after intravenous administration of 51Cr-albumin.

Three new species, two new genera, and new family Biphragmosagittidae (Сhaetognatha) from Southwest Pacific Ocean

2011 ◽  
Vol 20 (1) ◽  
pp. 161-173
Author(s):  
A.P. Kassatkina
Keyword(s):  
New Species ◽  
Type Species ◽  
Morphological Characters ◽  
The Body ◽  
New Order ◽  
New Genera ◽  
New Family ◽  
The Family ◽  
Three New Species

Resuming published and own data, a revision of classification of Chaetognatha is presented. The family Sagittidae Claus & Grobben, 1905 is given a rank of subclass, Sagittiones, characterised, in particular, by the presence of two pairs of sac-like gelatinous structures or two pairs of fins. Besides the order Aphragmophora Tokioka, 1965, it contains the new order Biphragmosagittiformes ord. nov., which is a unique group of Chaetognatha with an unusual combination of morphological characters: the transverse muscles present in both the trunk and the tail sections of the body; the seminal vesicles simple, without internal complex compartments; the presence of two pairs of lateral fins. The only family assigned to the new order, Biphragmosagittidae fam. nov., contains two genera. Diagnoses of the two new genera, Biphragmosagitta gen. nov. (type species B. tarasovi sp. nov. and B. angusticephala sp. nov.) and Biphragmofastigata gen. nov. (type species B. fastigata sp. nov.), detailed descriptions and pictures of the three new species are presented.

Visualization of Invasion into the Body and Internal Diffusion of Nanoparticles

2008 ◽  
Vol 396-398 ◽  
pp. 569-572
Author(s):  
Fumio Watari ◽  
Shigeaki Abe ◽  
I.D. Rosca ◽  
Atsuro Yokoyama ◽  
Motohiro Uo ◽  
...  
Keyword(s):  
Biomedical Applications ◽  
Fluorescent Microscopy ◽  
The Body ◽  
Internal Diffusion ◽  
Whole Body ◽  
X Ray ◽  
Body Level ◽  
Organ Level ◽  
Level 2 ◽  
Internal Body

Nanoparticles may invade directly into the internal body through the respiratory or digestive system and diffuse inside body. The behavior of nanoparticles in the internal body is also essential to comprehend for the realization of DDS. Thus it is necessary to reveal the internal dynamics for the proper treatments and biomedical applications of nanoparticles. In the present study the plural methods with different principles such as X-ray scanning analytical microscope (XSAM), MRI and Fluorescent microscopy were applied to enable the observation of the internal diffusion of micro/nanoparticles in the (1) whole body level, (2) inner organ level and (3) tissue and intracellular level. Chemical analysis was also done by ICP-AES for organs and compared with the results of XSAM mapping.

scholarly journals Making the choice between bioelectrical impedance measures for body hydration status assessment

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dmitry M. Davydov ◽  
Andrey Boev ◽  
Stas Gorbunov
Keyword(s):  
Body Schema ◽  
Bioelectrical Impedance ◽  
Information Criterion ◽  
The Body ◽  
Whole Body ◽  
Hydration Status ◽  
Status Assessment ◽  
Best Fitting ◽  
Body Compartments ◽  
Fitting In

AbstractSituational or persistent body fluid deficit (i.e., de- or hypo-hydration) is considered a significant health risk factor. Bioimpedance analysis (BIA) has been suggested as an alternative to less reliable subjective and biochemical indicators of hydration status. The present study aimed to compare various BIA models in the prediction of direct measures of body compartments associated with hydration/osmolality. Fish (n = 20) was selected as a biological model for physicochemically measuring proximate body compartments associated with hydration such as water, dissolved proteins, and non-osseous minerals as the references or criterion points. Whole-body and segmental/local impedance measures were used to investigate a pool of BIA models, which were compared by Akaike Information Criterion in their ability to accurately predict the body components. Statistical models showed that ‘volumetric-based’ BIA measures obtained in parallel, such as distance2/Rp, could be the best approach in predicting percent of body moisture, proteins, and minerals in the whole-body schema. However, serially-obtained BIA measures, such as the ratio of the reactance to resistance and the resistance adjusted for distance between electrodes, were the best fitting in predicting the compartments in the segmental schema. Validity of these results should be confirmed on humans before implementation in practice.

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