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At least 19 recordsLinked to original sources
PubMed1976

Usefulness of the group-comparison method to demonstrate sex differences in spatial orientation and spatial visualization in older men and women.

This paper reports an analysis of sex differences in cognitive test scores covering the dimensions of spatial orientation and spatial visualization in groups of 6 older men and 6 women matched for speed of performance on a maze test and level of performance on a spatial relations task. Older men were more proficient solving spatial problems using the body as a referent, whereas there was no significant difference between the sexes in imagining spatial displacement. Matched comparisons appear a useful adjunct to population research to understand the type(s) of cognitive processes where differential performance by the sexes is observed.

Age Factors↗
PubMed1992

The dynamics of spatial orientation during complex and changing linear and angular acceleration.

The dynamics of spatial orientation perception were examined in a series of experiments in which a total of 43 subjects were passively exposed to various combinations of linear and angular acceleration during centrifuge runs. Perceptual effects during deceleration were much stronger than effects during acceleration. The dynamics of spatial orientation perception differed substantially from changes in the vestibulo-ocular reflex (VOR). VOR was fairly well predicted by a current model, but our experiments revealed perceived change in attitude (roll, pitch, yaw tilt position in space) and perceived angular velocity in space that was not reflected by parallel changes in the plane or magnitude of the VOR. This series of experiments establishes several facts concerning spatial orientation perception beyond the predictive domain of any current model. New concepts are needed and several are suggested to deal with changing reactions to complex combinations of linear and angular accelerations.

Acceleration↗
PubMed1977

Training of spatial orientation with a senile demented patient. An experimental case study.

An 82 year old man, with the diagnosis senile dementia, was trained to find his own way to objects of importance on the ward (bed - toilet, dinner table - bed, dayroom - dinner table). The ward distances were divided into smaller units. A single case experimental design was used. During baseline the patient was given the opportunity to walk the distance. As long as he succeeded in finding the final destination, the distance was gradually extended one unit at a time. After one week each unit of the first distance was marked with a distinctive symbol and instructions were provided on their meaning. The two other distances served as control distances under baseline condition. One week later the second distance was also included in the intervention, while the third remained at baseline. Finally all distances were included in the intervention. There was a significant improvement in two of the three distances. This improvement was, however, only temporary.

Activities of Daily Living↗
PubMed1975

Response of the elasmobranch utricle to maintained spatial orientation, transitions and jitter.

1. The spike discharges of single first order afferents from the utricle were recorded in the isolated head of the guitarfish and tested for responses to maintained spatial orientation, to transitions and to a small positional jitter representing natural perturbations. Sensitivity to maintained orientation is referred to as "tonic", and to transitions and jitter as "phasic". 2. Most responsive cells were either phasically, or phasically and tonically sensitive. A few were exclusively tonic. Tonic responsiveness implied that maintained orientation was associated with a stationary discharge which differed from one position to another; it sometimes differed also from one station to another at the same position. Transitions from one position to another evoked a rate change that later adapted to the level of the tonic response. Opposite transitions evoked rate changes in the opposite sense. The phasic rate change was usually larger for transitions that increased the rate. Many units were non-responsive. The prevalence of phasic over tonic sensitivity is stressed, and the remarkable heterogeneity of utricular afferents confirms that the macula is not uniform, probably coding a wide variety of head accelerations. 3. The jitter increased the ongoing scatter of intervals and binrates, changing, complicating, or abolishing their periodicity. The jitter could influence the effects of maintained orientation, increasing, decreasing, inverting or even revealing directional sensitivity. It could also force previously independent units into an orientation-dependent correlation; hence, between-cell correlation is potentially useful in coding of spatiel orientation. Naturally occurring perturbations may sonstitute a significant issue of normal operation. 4. Certain afferents from the horizontal semicircular canal showed a slow tonic response to maintained spatial orientation.

Action Potentials↗
PubMed1979

Spatially oriented movements in the absence of proprioception.

Four patients, each with a cerebrovascular accident in a different arterial supply, had unilaterally impaired somatosensory function that included eficits in the perception of touch and proprioception. In spite of central nervous system lesions and absent proprioception, all patients accurately performed spatially oriented movements with the deafferented hand. These observations suggest that execution of certain motor programs can proceed effectively without peripheral feedback.

Adult↗
PubMed1979

Effects of genetic vestibular defects on behavior related to spatial orientation and emotionality.

A large battery of behavioral tests was administered to normal mice and to mice with varying degrees of otoconial agenesis due to genes affecting vestibular development. Many significant differences were found, but a factor analysis revealed that the variance on the 11 best tests could be accounted for in terms of two underlying variables. Factor I, the more important of the two, was associated with activity, habituation, and spontaneous alternation. Factor II appeared to represent a fear of new stimuli or situations. In both cases factor scores were highly related to the degree of otoconial deficiency. One subgroup of mice with severe otoconial agenesis displayed hyperactivity and a total absence of either habituation or spontaneous alternation. In these animals, brain and body development were stunted, and the reactions to amphetamine and physostigmine were opposite to those seen in normal mice. The results support the idea that the static organs contribute importantly to spatial orientation and suggest that early-onset vestibular defects can result in profound alterations of emotionality.

Acetylcholine↗
PubMed1978

Some influences of touch and pressure cues on human spatial orientation.

During constant velocity rotation about his recumbent Z axis, a blindfolded subject feels as if he were on an orbital path in the same direction. This experienced motion results from the pattern of touch and pressure stimulation of the body surface. If the subject changes the pressure pattern on his body by bracing himself in the rotating apparatus in different ways, it is possible for him to influence profoundly and systematically his apparent orientation. For example, pressure on the top of his head while he is rotating can make the subject feel he is upside down on a cylindrical path. The changes in apparent ongoing posture elicited by different patterns of pressure cues are very similar for different subjects and are constant for the same subject over time. During experienced orbital motion, a subject will hear a continuously emitting sound source--one that is stationary in the external environment--as circling his head in the direction opposite that of his true rotation. If the rotating subject is permitted unrestricted sight of his surroundings, he neither experiences orbital motion nor mislocalizes sounds. These observations provide insight into the spatial orientation mechanisms that normally allow an organism to distinguish accurately between those changes in activity at its receptors contingent on its own movements, and those resulting from movement within the environment. They also provide a way of understanding some of the postural illusions experienced during exposure to unusual force environments, including free fall.

Adolescent↗
PubMed1992

Selective corticosteroid antagonists modulate specific aspects of spatial orientation learning.

Receptors for mineralocorticoids (MRs) and glucocorticoids (GRs) display a high concentration and distinct distribution in the hippocampus. The effects of corticosteroids on behavior mediated by central MRs and GRs were assessed in rats. Spatial navigation is considered to be a sensitive measure for hippocampal functioning. Removal of circulating corticosteroids (via adrenalectomy) impaired spatial learning. In intact rats, blockade of central MRs and GRs by intracerebroventricular injection of selective MR and GR antagonists influenced different aspects of spatial learning. The analysis of the behavioral pattern revealed that treatment with the MR antagonist altered search-escape strategies in the water maze. The injection of the GR antagonist after training resulted in increased latencies to find the platform, which reflects the disturbed consolidation of spatial information. Corticosteroids affect in a differential and coordinated manner behavioral strategies and storage of spatial information.

Adrenal Medulla↗
PubMed1979

Spatial orientation and distribution of antigens within human glomerular basement membrane.

Antibodies to GBM have a linear staining pattern along the GBM by immunofluorescence. In this study, we have examined the distribution of human GBM antigens using Goodpasture antibody and heterologous rabbit anti-human GBM antibody. Goodpasture sera and Goodpasture antibody eluted from diseased kidneys reacted as a single linear component within the GBM. Rabbit anti-human GBM was shown to react along distinctly separate zones of the inner and outer aspects of the GBM; the central portion of the GBM seemed to be nonreactive with this antibody. In comparison, Goodpasture antibodies reacted along the inner zone of the GBM but at a locus external to that reacting with heterologous rabbit anti-GBM antibody. These observations of linear binding of antibody to different sites along the GBM suggest a spatial organization of antigen not previously observed.

Anti-Glomerular Basement Membrane Disease↗
PubMed1978

Spatial orientation of microtubules in contractile fibroblasts in vivo.

Contracting fibrous tissues from skin wounds in pigs, and scars around silicone implants in humans, contained fibroblasts that had multiple bundles of 60--80 A microfilaments with electron-dense bodies, features typical of contractile fibroblasts both in vivo (myofibroblasts) and in vitro. These in vivo fibroblasts contained many 220 A diameter microtubules, which paralleled plasma membrane in these myofibroblasts strongly suggests a bracing or scaffolding function.

Animals↗
PubMed1992

Spatial orientation in weightless environments.

Illusions of body inversion and of vehicle inversion can be evoked by exposure to weightlessness in the microgravity conditions of orbital and parabolic flight. Such illusions can involve all possible combinations of self-inversion and vehicle inversion. In the absence of any patterns of external stimulation, individuals may lose all sense of body orientation to their surroundings while retaining a sense of their overall body configuration and cognitive awareness of their actual position. Touch and pressure cues provide a perceptual 'down' in the absence of visual input. When vision is allowed, apparent orientation is influenced by a variety of factors including the direction of gaze, the architectural layout of the vehicle, and sight of the body. The relative importance of the various factors affecting orientation changes with repeated exposure. The virtual absence of sensations of falling during exposure to free-fall emphasizes the role of cognitive factors in experienced orientation.

Adolescent↗
PubMed1975

Sex differences in the comprehension of spatial orientation.

This research examined effects of instruction upon acquisition of Piaget's concept of horizontality and determined sex differences related to this acquisition. Hypotheses tested were that there are no significant differences (a) in performance on perception and prediction tasks, (b) by sex in the ability to comprehend horizontality, (c) by sex in the stage of development after instruction, and (d) by sex after instruction on the number of correct responses on horizontal tasks. Subjects were 18 male and 17 female rural, public school pupils ranging in age from 8 years, 0 months to 9 years, 11 months. Test instruments were a cylindrical bottle half-filled with colored water and eight pictures of bottles positioned at angles from 0 to 315 degrees at increments of 45 degrees. Chi square tests indicated that males performed significantly better than females on perception and prediction, and that instruction significantly improved male performance on prediction and female performance on prediction and perception. It was concluded that females, if given instruction, could more closely approximate the performance of males on the horizontal water level task.

Child↗
PubMed1978

Spatial orientation of glycoproteins in membranes of rat liver rough microsomes. I. Localization of lectin-binding sites in microsomal membranes.

Carbohydrate-containing structures in rat liver rough microsomes (RM) were localized and characterized using iodinated lectins of defined specificity. Binding of [125I]Con A increased six- to sevenfold in the presence of low DOC (0.04--0.05%) which opens the vesicles and allows the penetration of the lectins. On the other hand, binding of [125I]WGA and [125I]RCA increased only slightly when the microsomal vesicles were opened by DOC. Sites available in the intact microsomal fraction had an affinity for [125I]Con A 14 times higher than sites for lectin binding which were exposed by the detergent treatment. Lectin-binding sites in RM were also localized electron microscopically with lectins covalently bound to biotin, which, in turn, were visualized after their reaction with ferritin-avidin (F-Av) markers. Using this method, it was demonstrated that in untreated RM samples, binding sites for lectins are not present on the cytoplasmic face of the microsomal vesicles, even after removal of ribosomes by treatment with high salt buffer and puromycin, but are located on smooth membranes which contaminate the rough microsomal fraction. Combining this technique with procedures which render the interior of the microsomal vesicles accessible to lectins and remove luminal proteins, it was found that RM membranes contain binding sites for Con A and for Lens culinaris agglutinin (LCA) located exclusively on the cisternal face of the membrane. No sites for WGA, RCA, soybean (SBA) and Lotus tetragonobulus (LTA) agglutinins were detected on either the cytoplasmic or the luminal faces of the rough microsomes. These observations demonstrate that: (a) sugar moieties of microsomal glycoproteins are exposed only on the luminal surface of the membranes and (b) microsomal membrane glycoproteins have incomplete carbohydrate chains without the characteristic terminal trisaccharides N-acetylglucosamine comes from galactose comes from sialic acid or fucose present in most glycoproteins secreted by the liver. The orientation and composition of the carbohydrate chains in microsomal glycoproteins indicate that the passage of these glycoproteins through the Golgi apparatus, followed by their return to the endoplasmic reticulum, is not required for their biogenesis and insertion into the endoplasmic reticulum (ER) membrane.

Animals↗
PubMed1978

Spatial orientation of glycoproteins in membranes of rat liver rough microsomes. II. Transmembrane disposition and characterization of glycoproteins.

Rat liver microsomal glycoproteins were purified by affinity chromatography on concanavalin A Sepharose columns from membrane and content fractions, separated from rough microsomes (RM) treated with low concentrations of deoxycholate (DOC). All periodic acid-Schiff (PAS)-positive glycoproteins of RM showed affinity for concanavalin A Sepharose; even after sodium dodecyl sulfate (SDS) acrylamide gel electrophoresis, most of the microsomal glycoproteins bound [125I]concanavalin A added to the gels, as detected by autoradiography. Two distinct sets of glycoproteins are present in the membrane and content fractions derived from RM. SDS acrylamide gel electrophoresis showed that RM membranes contain 15--20 glycoproteins (15--22% of the total microsomal protein) which range in apparent mol wt from 23,000 to 240,000 daltons. A smaller set of glycoproteins (five to seven polypeptides), with apparent mol wt between 60,000 and 200,000 daltons, was present in the microsomal content fraction. The disposition of the membrane glycoproteins with respect to the membrane plane was determined by selective iodination with the lactoperoxidase (LPO) technique. Intact RM were labeled on their outer face with 131I and, after opening of the vesicles with 0.05% DOC, in both faces with 125I. An analysis of iodination ratios for individual proteins separated electrophoretically showed that in most membrane glycoproteins, tyrosine residues are predominantly exposed on the luminal face of the vesicles, which is the same face on which the carbohydrate moieties are exposed. Several membrane glycoproteins are also exposed on the cytoplasmic surface and therefore have a transmembrane disposition. In this study, ribophorins I and II, two integral membrane proteins (mol wt 65,000 and 63,000) characteristic of RM, were found to be transmembrane glycoproteins. It is suggested that the transmembrane disposition of the ribophorins may be related to their possible role in ribosome binding and in the vectorial transfer of nascent polypeptides into the microsomal lumen.

Animals↗
PubMed1979

Remodelling after distal forearm fractures in children. I. The effect of residual angulation on the spatial orientation of the epiphyseal plates.

The effect of residual fracture angulation on the distal radial and ulnar epiphyseal plates was studied in children aged 1 to 15 years. Thirty-eight fractures located in the distal fifth of the forearm bones were observed for 1 to 25 months after the fractures had healed. The forearms were examined radiographically on two to five occasions and the inclinations of the epiphyseal plates in relation to the long axis of the proximal fragments were measured. The results showed that an abnormal inclination of the epiphyseal plate after healing of a distal forearm fracture induced an alteration of growth in the epiphyseal plate. The redistribution of growth tended to correct the abnormal inclination. The rate of correction followed an exponential course. The age of the child at the time of the fracture and the distance from the fracture to the epiphyseal plate did not influence the capacity for correction.

Adolescent↗