scholarly journals A quantitative framework for whole-body coordination reveals specific deficits in freely walking ataxic mice

eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
Ana S Machado ◽  
Dana M Darmohray ◽  
João Fayad ◽  
Hugo G Marques ◽  
Megan R Carey
Keyword(s):  
Motor Control ◽  
Body Size ◽  
Purkinje Cell ◽  
Walking Speed ◽  
The Body ◽  
Whole Body ◽  
Gait Ataxia ◽  
Cell Degeneration ◽  
Forward Motion ◽  
Circuit Defects

The coordination of movement across the body is a fundamental, yet poorly understood aspect of motor control. Mutant mice with cerebellar circuit defects exhibit characteristic impairments in locomotor coordination; however, the fundamental features of this gait ataxia have not been effectively isolated. Here we describe a novel system (LocoMouse) for analyzing limb, head, and tail kinematics of freely walking mice. Analysis of visibly ataxic Purkinje cell degeneration (pcd) mice reveals that while differences in the forward motion of individual paws are fully accounted for by changes in walking speed and body size, more complex 3D trajectories and, especially, inter-limb and whole-body coordination are specifically impaired. Moreover, the coordination deficits in pcd are consistent with a failure to predict and compensate for the consequences of movement across the body. These results isolate specific impairments in whole-body coordination in mice and provide a quantitative framework for understanding cerebellar contributions to coordinated locomotion.

scholarly journals Allometry in desert ant locomotion (Cataglyphis albicans and Cataglyphis bicolor) – does body size matter?

2021 ◽  
Author(s):  
Johanna Tross ◽  
Harald Wolf ◽  
Sarah Elisabeth Pfeffer
Keyword(s):  
Body Size ◽  
Walking Speed ◽  
The Body ◽  
Size Spectrum ◽  
Similar Species ◽  
Data Set ◽  
Desert Ant ◽  
Walking Speeds ◽  
Size Matter ◽  
Cataglyphis Bicolor

Desert ants show a large range of adaptations to their habitats. They can reach extremely high running speeds, for example, to shorten heat stress during foraging trips. It has recently been examined how fast walking speeds are achieved in different desert ant species. It is intriguing in this context that some species exhibit distinct intraspecific size differences. We therefore performed a complete locomotion analysis over the entire size spectrum of the species Cataglyphis bicolor, and we compared this intraspecific data set with that of the allometrically similar species Cataglyphis albicans. Emphasis was on the allometry of locomotion: we considered the body size of each animal and analysed the data in terms of relative walking speed. Body size was observed to affect walking parameters, gait patterns and phase relations in terms of absolute walking speed. Unexpectedly, on a relative scale, all ants tended to show the same overall locomotion strategy at slow walking speeds, and significant differences occurred only between C. albicans and C. bicolor at high walking speeds. Our analysis revealed that C. bicolor ants use the same overall strategy across all body sizes, with small ants reaching the highest walking speeds (up to 80 body lengths s−1) by increasing their stride lengths and incorporating aerial phases. By comparison, C. albicans reached high walking speeds mainly by a high synchrony of leg movement, lower swing phase durations and higher stride frequencies ranging up to 40 Hz.

scholarly journals Patterns and potential drivers of intraspecific variability in the body elemental composition of a terrestrial consumer, the snowshoe hare (Lepus americanus)

2019 ◽  
Author(s):  
Matteo Rizzuto ◽  
Shawn J. Leroux ◽  
Eric Vander Wal ◽  
Yolanda F. Wiersma ◽  
Travis R. Heckford ◽  
...  
Keyword(s):  
Body Size ◽  
Chemical Composition ◽  
Intraspecific Variability ◽  
Lepus Americanus ◽  
The Body ◽  
Whole Body ◽  
Snowshoe Hare ◽  
Weak Relationship ◽  
Snowshoe Hares ◽  
P Content

AbstractIntraspecific variability in ecological traits is widespread in nature. Recent evidence, mostly from aquatic ecosystems, shows individuals differing at the most fundamental level, that of their chemical composition. Age, sex, or body size may be key drivers of intraspecific variability in the body concentrations of carbon (C), nitrogen (N), and phosphorus (P). However, we still have a rudimentary understanding of the patterns and drivers of intraspecific variability in chemical composition of terrestrial consumers, particularly vertebrates.Here, we investigate the whole-body chemical composition of snowshoe hare Lepus americanus, providing one of the few studies of patterns of stoichiometric variability and its potential drivers for a terrestrial vertebrate. Based on snowshoe hare ecology, we expected higher P and N concentrations in females, as well as in larger and older individuals.We obtained whole-body C, N, and P concentrations and C:N, C:P, N:P ratios from a sample of 50 snowshoe hares. We then used general linear models to test for evidence of a relationship between age, sex, or body size and stoichiometric variability in hares.We found considerable variation in the C, N, and P concentrations and elemental ratios within our sample. Contrary to our predictions, we found evidence of N content decreasing with age. As expected, we found evidence of P content increasing with body size. As well, we found no support for a relationship between sex and N or P content, nor for variability in C content and any of our predictor variables.Despite finding considerable stoichiometric variability in our sample, we found no substantial support for age, sex, or body size to relate to this variation. The weak relationship between body N concentration and age may suggest varying nutritional requirements of individuals at different ages. Conversely, P’s weak relationship to body size appears in line with recent evidence of the potential importance of P in terrestrial systems. Snowshoe hares are a keystone herbivore in the boreal forest of North America. The substantial stoichiometric variability we find in our sample could have important implications for nutrient dynamics in both boreal and adjacent ecosystems.

The control of somitogenesis in mouse embryos

Development ◽  
1981 ◽  
Vol 65 (Supplement) ◽  
pp. 103-128
Author(s):  
P. P. L. Tam
Keyword(s):  
Body Size ◽  
Primitive Streak ◽  
Mouse Embryos ◽  
The Body ◽  
Whole Body ◽  
Axis Formation ◽  
Presomitic Mesoderm ◽  
Tail Bud ◽  
Somite Formation ◽  
Somitic Mesoderm

Somitogenesis in the mouse embryo commences with the generation of presumptive somitic mesoderm at the primitive streak and in the tail-bud mesenchyme. The presumptive somitic mesoderm is then organized into somite primordia in the presomitic mesoderm. These primordia undergo morphogenesis leading to the segmentation of somites at the cranial end of the presomitic mesoderm. Somite sizes at the time of segmentation vary according to the position of the somite in the body axis: the size of lumbar and sacral somites is nearly twice that of upper trunk somites and of tail somites. The size of the presomitic mesoderm, which is governed by the balance between the addition of cells at the caudal end and the removal of somites at the cranial end, changes during embryonic development. Somitogenesis is disturbed during the compensatory growth of mouse embryos which have suffered a drastic size reduction at the primitive-streak and early-organogenesis stages. The formation of somites is retarded and the upper trunk somites are formed at a smaller size. The embryo also follows an entirely different growth profile, but a normal body size is restored by the early foetal stage. The somite number is regulated to normal and this is brought about by an altered rate of somite formation and the adjustment of somite size in proportion to the whole body size. It is proposed that axis formation and somitogenesis are related morphogenetic processes and that embryonic growth controls the kinetics of somitogenesis, namely by regulating the number of cells allocated to each somite and the rate of somite formation.

Coordination variability during running in adolescents with autism spectrum disorder

Autism ◽  
2021 ◽  
pp. 136236132110443
Author(s):  
Hunter J Bennett ◽  
Taylor Jones ◽  
Kevin A Valenzuela ◽  
Justin A Haegele
Keyword(s):  
Physical Activity ◽  
Body Mass Index ◽  
Motor Control ◽  
Body Mass ◽  
Mixed Model ◽  
Autism Spectrum ◽  
The Body ◽  
Whole Body ◽  
Coordination Patterns ◽  
Main Effects

Autistic persons exhibit variable movement, loading, and coordination patterns during walking. While much research has examined walking, little to no research exists regarding running for autistic persons despite its prevalence and benefits as a mode of physical activity. This study determined if autistic adolescents demonstrate increased coordination variability during running compared to matched controls. Seventeen autistic adolescents (aged = 13–18 years) and seventeen sex, age, and body mass index matched controls performed running at two matched speeds: self-selected of autistic adolescents and at 3.0 m/s. Modified vector coding was used to determine the patterns of movement for foot-shank, shank-thigh, left/right thigh, and contralateral arm-thigh coupling. Coordination variability, measuring cycle-to-cycle variability, was determined during loading response and pushoff phases. Mixed-model analyses of variance were used to determine group by speed interactions and main effects. Coordination variability was nearly 2× larger (all p < 0.001) in autistic adolescents compared to controls. Speed main effects were found for several sagittal plane couples during loading response. In agreement with walking analyses, this study illustrates that autistic adolescents run with increased intra-limb, inter-limb, and cross-body coordination variability. Like walking, increased coordination variability during running may negatively impact this mode of physical activity for autistic persons. Lay abstract Walking and running are popular forms of physical activity that involve the whole body (pelvis/legs and arms/torso) and are coordinated by the neuromuscular system, generally without much conscious effort. However, autistic persons tend not to engage in sufficient amounts of these activities to enjoy their health benefits. Recent reports indicate that autistic individuals tend to experience altered coordination patterns and increased variability during walking tasks when compared to non-autistic controls. Greater stride-to-stride coordination variability, when the task has not changed (i.e. walking at same speed and on same surface), is likely indicative of motor control issues and is more metabolically wasteful. To date, although, research examining running is unavailable in any form for this population. This study aimed to determine if coordination variability during running differs between autistic adolescents and age, sex, and body mass index matched non-autistic controls. This study found that increased variability exists throughout the many different areas of the body (foot-leg, left/right thighs, and opposite arm-opposite thigh) for autistic adolescents compared to controls. Along with previous research, these findings indicate autistic persons exhibit motor control issues across both forms of locomotion (walking and running) and at multiple speeds. These findings highlight issues with motor control that can be addressed by therapeutic/rehabilitative programming. Reducing coordination variability, inherently lessening metabolic inefficiency, may be an important step toward encouraging autistic youth to engage in sufficient physical activity (i.e. running) to enjoy physiological and psychological benefits.

scholarly journals Shared and specific signatures of locomotor ataxia in mutant mice

2020 ◽  
Author(s):  
Ana S. Machado ◽  
Hugo G. Marques ◽  
Diogo F. Duarte ◽  
Dana M. Darmohray ◽  
Megan R. Carey
Keyword(s):  
Discriminant Analysis ◽  
Motor Coordination ◽  
Locomotor Behavior ◽  
Whole Body ◽  
Gait Ataxia ◽  
Cell Degeneration ◽  
Linear Discriminant ◽  
Mouse Mutants ◽  
Compare And Contrast ◽  
The Brain

AbstractSeveral spontaneous mouse mutants with deficits in motor coordination and associated cerebellar neuropathology have been described. Intriguingly, both visible gait alterations and neuroanatomical abnormalities throughout the brain differ across mutants. We previously used the LocoMouse system to quantify specific deficits in locomotor coordination in mildly ataxic Purkinje cell degeneration mice (pcd; Machado et al., 2015). Here, we analyze the locomotor behavior of severely ataxic reeler mutants and compare and contrast it with that of pcd. Despite clearly visible gait differences, direct comparison of locomotor kinematics and linear discriminant analysis reveal a surprisingly similar pattern of impairments in multijoint, interlimb, and whole-body coordination in the two mutants. These findings capture both shared and specific signatures of gait ataxia and provide a quantitative foundation for mapping specific locomotor impairments onto distinct neuropathologies in mice.

scholarly journals Shared and specific signatures of locomotor ataxia in mutant mice

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Ana S Machado ◽  
Hugo G Marques ◽  
Diogo F Duarte ◽  
Dana M Darmohray ◽  
Megan R Carey
Keyword(s):  
Discriminant Analysis ◽  
Motor Coordination ◽  
Locomotor Behavior ◽  
Whole Body ◽  
Gait Ataxia ◽  
Cell Degeneration ◽  
Linear Discriminant ◽  
Mouse Mutants ◽  
Compare And Contrast ◽  
The Brain

Several spontaneous mouse mutants with deficits in motor coordination and associated cerebellar neuropathology have been described. Intriguingly, both visible gait alterations and neuroanatomical abnormalities throughout the brain differ across mutants. We previously used the LocoMouse system to quantify specific deficits in locomotor coordination in mildly ataxic Purkinje cell degeneration mice (pcd; Machado et al., 2015). Here, we analyze the locomotor behavior of severely ataxic reeler mutants and compare and contrast it with that of pcd. Despite clearly visible gait differences, direct comparison of locomotor kinematics and linear discriminant analysis reveal a surprisingly similar pattern of impairments in multijoint, interlimb, and whole-body coordination in the two mutants. These findings capture both shared and specific signatures of gait ataxia and provide a quantitative foundation for mapping specific locomotor impairments onto distinct neuropathologies in mice.

scholarly journals The Functional Significance of the Hypocercal Tail in Pteraspis Rostrata

1943 ◽  
Vol 20 (1) ◽  
pp. 23-27
Author(s):  
K. A. KERMACK
Keyword(s):  
Functional Significance ◽  
The Body ◽  
Whole Body ◽  
Forward Movement ◽  
Forward Motion

1. An attempt has been made to determine the functional significance of the hypocercal tail in the swimming of one of those Ostracoderms which possessed it, Pteraspis rostrata. 2. Since Pteraspis was almost certainly denser than the medium in which it lived, a dynamic upthrust (lift) would have to be generated by forward motion. It is suggested that this lift was obtained by an inclination of the whole body of the animal to act as a lifting plane during forward movement. 3. The hypocercal tail would depress the hinder end of the body, so giving rise to the required inclination. This, it is suggested, was its functional significance in Pteraspis. 4. The above would apply to all those Ostracoderms (Anaspida and Heterostraci) with the hypocercal form of tail.

Scale effects in the kinematics and dynamics of swimming leeches

1998 ◽  
Vol 76 (10) ◽  
pp. 1869-1877 ◽  
Author(s):  
Christopher E Jordan
Keyword(s):  
Body Size ◽  
Scale Effects ◽  
Kinematic Parameter ◽  
The Body ◽  
Wave Number ◽  
Whole Body ◽  
Kinematics And Dynamics ◽  
Size Dependent ◽  
Swimming Mode ◽  
Swimming Kinematics

Slender-bodied organisms swimming with whole-body undulations exhibit what appears to be a high degree of kinematic parameter conservation, which is independent of body size. However, organisms of very different sizes swim in fundamentally different physical realms, owing to the relative scaling of viscous and inertial fluid stresses as a function of size and speed. In light of the size-dependent fluid forces, the kinematic constancy suggests three hypotheses: (1) swimming organisms adopt a single "ideal" swimming mode requiring the modification of muscle forces or motor patterns through ontogeny, (2) swimming kinematics are determined predominantly by the passive mechanical interaction of the body and the fluid, resulting in a single swimming mode independent of absolute body size, or (3) while undulatory swimming kinematics may be similar between organisms, there are important size-dependent kinematic differences. In this study, I address this issue by examining the swimming kinematics and dynamics of the medicinal leech Hirudo medicinalis L. as a function of body size. Over a 5-fold increase in body length, the relative amplitude of body undulations during swimming did not change; however, swimming speed, propulsive wave speed, and propulsive wave frequency all decreased, while propulsive wave number increased slightly, strongly supporting hypothesis 2. To determine the source of the observed size-dependent swimming kinematics, I manipulated the dynamic viscosity of the organism's fluid environment to alter the constraints placed on swimming behavior by the physical surroundings. In the elevated-viscosity treatment, all kinematic parameters changed in the opposite direction to that predicted by hypothesis 2, rejecting both the idea that swimming kinematics are simply determined by passive mechanical interactions and that leeches have a target swimming mode under active control.

A new acanthocephalan of the genus Pallisentis recovered from intestine of Channa striatus from Imphal-East , Manipur (India)

2021 ◽  
Vol 27 (1) ◽  
Author(s):  
N. Pengki Devi ◽  
R.K. Gambhir
Keyword(s):  
New Species ◽  
Body Size ◽  
Body Length ◽  
The Body ◽  
Whole Body ◽  
Middle Portion ◽  
Present Specimen ◽  
Channa Striatus

The new species is characterized by possessing medium body size, 4 rows of 9 hooks each, a faded fork like structure present in the proboscis, a collar of spine consisting of 15 rows of 8- 10 spines each, cylindrical testes, poorly develoved uterine bell. The eggs are present in the middle portion of the body and spines are present only in one third portion of the whole body length and the rest portion is devoid of spine. The present specimen deals with the description of Pallisentis heingangyensis n. sp. recovered from the intestine of Channa striatus from Heingang river, Imphal East, Manipur.

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