Vestibular memory-contingent saccades involve somatosensory input from the body support

The results of a study of existing lunar-gravity simulators indicated that a number of improvements could be made in the simulators being used to study the effects of reduced or lunar gravity on man's self-locomotive capability. This paper presents a review of a prototype lunar-gravity simulator which was designed, built, and delivered to NASA Langley Research Center by the Case Western Reserve Institute and the Cleveland Institute of Art. The simulator utilizes novel magnetic air bearings with constant-force motors and a unique body support system in that each of the body members are independently supported.

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Design of Active Suspensions

Proceedings of the Institution of Mechanical Engineers ◽

10.1243/pime_proc_1970_185_060_02 ◽

1970 ◽

Vol 185 (1) ◽

pp. 553-563 ◽

Cited By ~ 58

Author(s):

A. G. Thompson

Keyword(s):

Synthesis Method ◽

The Body ◽

Ride Quality ◽

Active Suspensions ◽

Simple Method ◽

Signal Flow ◽

In Series ◽

Body Load ◽

Conventional Systems ◽

Body Support

The synthesis method is employed for the design of servo-suspensions of the electro-hydraulic type. Two alternative arrangements are considered in which the hydraulic actuators and the body support springs are respectively in series and in parallel. The achieved designs for active suspensions of this type are superior to conventional systems both in ride quality and in overall stiffness to resist body load forces, but slightly less effective in regard to road-holding. If dynamic absorbers are used for the control of axle vibrations it is shown that considerably greater improvements in ride quality than hitherto possible may be obtained with the aid of an additional feedforward compensating signal flow path. The derivation of the necessary compensation circuits to achieve the specified overall system performances is demonstrated by examples. A simple method of banking control of the vehicle by inclined sensing accelerometers is suggested.

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ACTIVE COIL-CORE SYSTEM AS A PART OF RIGID BODY SUPPORT AND ITS INFLUENCE ON THE BODY VIBRATIONS

Mechanics and Control ◽

10.7494/mech.2012.31.1.16 ◽

2012 ◽

Vol 31 (1) ◽

pp. 16 ◽

Cited By ~ 1

Author(s):

Mirosław KONDRATIUK ◽

Zbigniew GOSIEWSKI ◽

Leszek AMBROZIAK

Keyword(s):

Rigid Body ◽

The Body ◽

Core System ◽

Body Support

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Mesodermal pattern and pattern repeats in the starfish bipinnaria larva, and related patterns in other deuterostome larvae and chordates

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.1996.0155 ◽

1996 ◽

Vol 351 (1348) ◽

pp. 1737-1758 ◽

Cited By ~ 20

Keyword(s):

Cell Types ◽

The Body ◽

Pisaster Ochraceus ◽

Internal Structures ◽

Distinctive Type ◽

In Series ◽

Body Wall Musculature ◽

Open Question ◽

Longitudinal Muscles ◽

Body Support

The arrangement of the body-wall musculature and supporting mesenchyme of the bipinnaria larva of Disaster ochraceus is described, based on an EM analysis of Pisaster ochraceus larvae. There are four main cell types: (i) a generalized mesenchyme that links the ectoderm with internal structures, e.g. coelom and gut; (ii) dorsal longitudinal muscles, which flex the body; (iii) oral-field muscles, which flex the larval lobes individually; and (iv) cords of subtrochal cells, a distinctive type of mesenchyme located beneath the ciliary band. Processes from the subtrochal cells insert into the band and associate closely with the ciliary nerve. The function the subtrochal cells perform is not obvious, but a role in body support is proposed, with the cells acting as tensile elements to increase the structural stability of the band. The insertions formed by the subtrochal cells could be attachm ent structures or, assuming the cells are contractile, they could be innervation sites. The larval lobes in the bipinnaria are arranged in series along the body, and the muscles that supply them are also arranged in series. Similar patterns of repeating elements occur in other echinoderm larvae, in the hemichordate tornaria larva, and also in chordates. In particular, there are marked similarities between (i) the arrangem ent of the oral-field muscles in the bipinnaria and the muscle bands of pelagic tunicates, and (ii) the subtrochal cells in the bipinnaria and the myotomes in Amphioxus . These similarities are suggestive; whether they are due to homology is an open question. On the assumption that they may, a hypothesis is proposed to explain the differences between anterior and posterior mesodermal repeats in vertebrates (somitomeres and somites) based on differences between anterior and posterior lobes in the bipinnaria.

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AGE-RELATED CHANGES IN THE MUSCLE SECRETOME

Innovation in Aging ◽

10.1093/geroni/igz038.378 ◽

2019 ◽

Vol 3 (Supplement_1) ◽

pp. S101-S101

Author(s):

Ning Zhang ◽

Susan Weintraub ◽

Nicolas Musi

Keyword(s):

Mass Spectrometry ◽

Aging Process ◽

Young Group ◽

The Body ◽

Age Related ◽

Secretion Profile ◽

And Function ◽

Old Mice ◽

Body Support ◽

Age Related Changes

Abstract Skeletal muscle is one of the most abundant tissues in the body. In addition to its key roles in body support, movement and metabolic homeostasis, muscle also functions as an endocrine/secretory organ producing and releasing proteins into the circulation that modulate distant tissues (i.e. myokines). Considering that muscle mass and function changes with advancing age, here we tested the hypothesis that aging alters the muscle secretome profile. After euthanasia, soleus muscles from sedentary young and old mice were dissected, and incubated in oxygenated KRB buffer for 2 h. The buffer was subjected to in-gel trypsin-digestion and peptides analyzed by mass spectrometry. The concentration of 36 proteins were significantly (P<0.05) elevated in the young vs. the old group. In contrast, only 7 proteins were significantly elevated in the old group. Some notable differences include those in HSPA1B and HSPA5 that were detected only in the young group. HSPA8 also was significantly elevated by 1.8-fold (P<0.05) in the young versus the old group. Another prominent difference between groups involved translationally controlled tumor protein (TCTP), a critical regulator of apoptosis/carcinogenesis, that was elevated by 7-fold in the young vs. the old group (P<0.05). These results indicate that aging alters the muscle secretion profile. Identified differences in the muscle secretome could reflect intrinsic changes in muscle cells with age. Because these myokines are released into the circulation, it is also possible that myokine secretion is a regulated cellular process by which muscle communicates and modulates the aging process in distant tissues.

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Projection from dorsal column nuclei to dorsal mesencephalon

Journal of Neurophysiology ◽

10.1152/jn.1985.53.1.183 ◽

1985 ◽

Vol 53 (1) ◽

pp. 183-200 ◽

Cited By ~ 18

Author(s):

L. L. Cooper ◽

J. O. Dostrovsky

Keyword(s):

Superior Colliculus ◽

Inferior Colliculus ◽

Receptive Fields ◽

Dorsal Column ◽

The Body ◽

Projection Neurons ◽

Dorsal Column Nuclei ◽

Wide Range ◽

Somatosensory Input ◽

Medial Geniculate

This study investigated the projection from the dorsal column nuclei (DCN) to the dorsal mesencephalon. Single-unit extracellular recordings were obtained from the DCN of alpha-chloralose anesthetized cats. Neurons were identified by standard antidromic stimulation criteria as projecting to the dorsal mesencephalon (M neurons), the diencephalon (D neurons), or to both regions (MD neurons). Fifty-two neurons could be antidromically activated from the dorsal mesencephalon. Of these, 31 could also be antidromically activated by stimulation in the diencephalon. An additional 34 neurons were studied that could be antidromically activated only from the diencephalon. Stimulation sites within the dorsal mesencephalon effective in antidromically activating M and MD neurons were in the caudal ventrolateral superior colliculus, the intercollicular area, and external nucleus of the inferior colliculus. Effective diencephalic stimulation sites were in the ventroposterolateral nucleus, the zona incerta, and the magnocellular division of the medial geniculate. The antidromic latencies to stimulation in the dorsal mesencephalon of M and MD neurons spanned a similar but wide range of values in contrast to the latencies to stimulation in the diencephalon of D neurons which were all short. Conduction velocities along the mesencephalic and diencephalic collaterals of MD neurons were similar. Many of the neurons projecting to the mesencephalon had receptive fields located proximally on the body. Most of the neurons had rapidly adapting responses to low-intensity mechanical stimulation of the skin. The major difference between the mesencephalic M and MD projection neurons and diencephalic projection D neurons was the larger percentage of neurons having proximal receptive fields in the former group. These findings are the first electrophysiological demonstration of a direct somatosensory input to the dorsal mesencephalon arising in the DCN. This input is probably responsible for providing some of the somatosensory input to the deeper layers of the superior colliculus, the external nucleus of the inferior colliculus, and the intercollicular area, regions known to have neurons responding to somatosensory stimuli.

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Postural Control in the Rabbit Maintaining Balance on the Tilting Platform

Journal of Neurophysiology ◽

10.1152/jn.00590.2003 ◽

2003 ◽

Vol 90 (6) ◽

pp. 3783-3793 ◽

Cited By ~ 46

Author(s):

I. N. Beloozerova ◽

P. V. Zelenin ◽

L. B. Popova ◽

G. N. Orlovsky ◽

S. Grillner ◽

...

Keyword(s):

Frontal Plane ◽

Threshold Value ◽

Dorsal Side ◽

The Body ◽

Body Posture ◽

Vestibular Input ◽

Postural Responses ◽

Extensor Muscles ◽

Somatosensory Input ◽

Emg Patterns

A deviation from the dorsal-side-up body posture in quadrupeds activates the mechanisms for postural corrections. Operation of these mechanisms was studied in the rabbit maintaining balance on a platform periodically tilted in the frontal plane. First, we characterized the kinematics and electromyographic (EMG) patterns of postural responses to tilts. It was found that a reaction to tilt includes an extension of the limbs on the side moving down and flexion on the opposite side. These limb movements are primarily due to a modulation of the activity of extensor muscles. Second, it was found that rabbits can effectively maintain the dorsal-side-up body posture when complex postural stimuli are applied, i.e., asynchronous tilts of the platforms supporting the anterior and posterior parts of the body. These data suggest that the nervous mechanisms controlling positions of these parts of the body can operate independently of each other. Third, we found that normally the somatosensory input plays a predominant role for the generation of postural responses. However, when the postural response appears insufficient to maintain balance, the vestibular input contributes considerably to activation of postural mechanisms. We also found that an asymmetry in the tonic vestibular input, caused by galvanic stimulation of the labyrinths, can affect the stabilized body orientation while the magnitude of postural responses to tilts remains unchanged. Fourth, we found that the mechanisms for postural corrections respond only to tilts that exceed a certain (threshold) value.

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Design Criteria for the Measurement of Pressure at Body/Support Interfaces

Engineering in Medicine ◽

10.1243/emed_jour_1980_009_052_02 ◽

1980 ◽

Vol 9 (4) ◽

pp. 209-214 ◽

Cited By ~ 37

Author(s):

M W Ferguson-Pell

Keyword(s):

Measurement Error ◽

The Body ◽

Maximum Diameter ◽

Design Criteria ◽

Calibration Technique ◽

Pressure Transducers ◽

Interface Curvature ◽

Design Characteristics ◽

Support Surfaces ◽

Body Support

The design characteristics of pressure transducers for use at interfaces between the body and support surfaces such as mattresses, cushions, prosthetic sockets, and beneath bandages are discussed, and criteria for determining the maximum diameter and thickness of suitable devices are developed analytically. Sources of measurement error including transducer response to interface curvature, off-axis stresses, environmental factors and hysteresis are identified. The need for a calibration technique compatible with the mechanical conditions under which measurements are made is emphasized.

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Attenuated Input to the Primary Somatosensory Cortex is Associated with the Occurrence of Rubber Hand Illusion

10.21203/rs.3.rs-141539/v1 ◽

2021 ◽

Author(s):

Masanori Sakamoto ◽

Hirotoshi Ifuku

Keyword(s):

Somatosensory Cortex ◽

Early Response ◽

The Body ◽

Neural Representation ◽

Rubber Hand Illusion ◽

Primary Somatosensory Cortex ◽

Somatosensory Processing ◽

Rubber Hand ◽

Somatosensory Input ◽

The Brain

Abstract The neural representation of the body is easily altered by the integration of multiple sensory signals in the brain. The “rubber hand illusion” (RHI) is one of the most popular experimental paradigms to investigate this phenomenon. During this illusion, ownership of the rubber hand is created. Some studies have shown that somatosensory processing in the brain is attenuated when RHI occurs. However, it is unknown where attenuation of somatosensory inputs occurs. Here, we show that somatosensory input from the hand is attenuated at the primary somatosensory cortex. We found that the early response of somatosensory evoked potential, which is thought to originate from the primary somatosensory cortex, was attenuated during RHI. Furthermore, this attenuation was observed before the occurrence of the illusion. Our results suggest that attenuation of somatosensory inputs from the hand to the brain is one of the factors influencing the occurrence of the RHI.

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