摘要:

The mechanical laws which make possible several characteristic and well-known modes of primate locomotion are reviewed. Biological requirements are fulfilled in small and in large primates by utilizing different mechanical principles. On the basis of the mechanics, special morphological traits can be identified which are advantageous for performing these locomotor modes, and which determine different lifestyles. These morphological ‘adaptations’ consequently are different in larger and smaller primates. The divergence between large and small forms is clarified by the inclusion of non-primate mammals into the comparis

ISSN:0015-5713    

DOI:10.1159/000157188

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

The development of quadrupedal walking in infant Japanese macaques (Macaca fuscata) was studied on the basis of their footfall patterns. Lateral views of the walking of 5 monkeys were taken by a video-camera and the timing of touchdown and liftoff was recorded. The total number of trials was 435. The change of footfall patterns during development was complicated. Four stages could be discerned, as in behavioural studies. In the first stage, there was a wide variation. The dominant patterns were the diagonal sequence which included any type of couplet in the second stage and trot in the third stage. There were two groups of footfall patterns in the fourth stage which were the diagonal sequence – diagonal couplet and the lateral sequence – lateral couplet. It seems that the stages reflect aspects of the development of both the neural system and the musculoskeletal sys

ISSN:0015-5713    

DOI:10.1159/000157189

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Bipedal walking was studied in chimpanzees between 1 and 19 years of age by measuring the external energy generated by the movement of the centre of gravity of the body. The ‘recovery’ of external energy in infant chimpanzees less than five years of age is smaller than in juveniles from 5 to 19 years of age. During the single stance phase, the short, flexed hindlimb of chimpanzees younger than 5 years is not able to lift the body centre of gravity high enough, so that these infants have a considerable energy output during bipedal walking. Extension of the hindlimb is one of the bases for energy economy in human bipedalism. The development of this low-energy-cost mechanism is an important component of the evolution of human bipedal

ISSN:0015-5713    

DOI:10.1159/000157190

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Bipedal walking by common chimpanzees is known to differ both kinematically and kinetically from human bipedalism, in particular by the adoption of flexed-knee gaits and characteristically single-peaked vertical ground reaction force curves. This study provides a test of the proposition that the two former mechanical characteristics are functionally related. Further, it examines the pattern of forces occurring during normal human bipedal walking at slow, normal and fast velocities; and during walking imitating bipedal walking of the common chimpanzee, by both male and female human adults and children. The data suggest that naturally reared chimpanzees walk with greater lateral forces than do adult humans walking erect. Women show greater variance in force parameters than do men; and children more than do adults, but men walk with greater vertical accelerations of the centre of mass, and sharper peaks of sagittal acceleration and deceleration than women. Data from both forceplate and pressure-pad records suggest that young children (and a chimpanzee for which force-plate data was available) accelerate using the heel, rather than the anterior part of the foot. A principal component analysis of Fourier coefficients for the force curves shows that forces produced by adults imitating chimpanzee gaits are intermediate between those produced in normal human gait and those produced by ‘real’ chimpanzees, confirming a functional connection between knee and hip kinematics during bipedal walking and the shape of the vertical ground reaction force curve. Human flexed-knee, flexed-hip walking is found to produce in-phase fluctuations in potential and kinetic energies, preventing the energy exchange which obtains in erect walking. Finally, computer simulations of bipedal walking indicate that kinematics are more influential determinants of ground reaction forces than are body paramet

ISSN:0015-5713    

DOI:10.1159/000157191

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Parameters of walking at ordinary, fast and slow speeds in 30 male and 30 female young adults were investigated. More than 10 trials were made for each speed by each subject. The number of subjects and trials was large enough to permit a statistical analysis. The focus of the study was the movement of the point where the resultant foot-ground force intersects the ground. Its pathway, or trajectory, begins at touchdown from the middle part of the heel, then runs quickly on a straight line to the heads of the first or second metatarsal bones, turns medially and moves slowly towards the base of the first toe, ending at the tip of the first or second toe, or between them. This result confirms that the ankle joint works like a hinge during the stance phase, and that the human foot structure is relatively robust. Remarkably high positive correlations between stride length and stature, as well as iliospinal height were found in male subjects. However in females these clear correlations were not found, except at fast walking speeds, although were not so notable as in males. Correlations calculated from the data from all female subjects indicated significantly quite high values, as in males, but it is almost impossible to estimate exact stature or iliospinal height reliably from stride length because of its relative high variation. The sexual difference in walking speed is not due to stride duration, but to stride length.

ISSN:0015-5713    

DOI:10.1159/000157192

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Joint mobility is a critical issue in the analysis of locomotor adaptation. Here we have attempted precise measurements of the range of extension/flexion of the hip, knee, and ankle joints of Japanese macaques by using fresh cadavers and devising an effective method to fixate the proximal segment. Severance of biarticular muscles revealed restrictions in mobility of as much as 10–25% caused by these muscles. However, incidences of an incomplete removal of the restriction through severance suggest a contribution of cutaneous tissues to the restriction. The mobility ranges determined by this method were compared with the joint motion of Japanese macaques during actual locomotio

ISSN:0015-5713    

DOI:10.1159/000157193

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

To initiate and terminate bipedal and quadrupedal locomotor movements, a smooth transition to and from standing is necessary. For this, integration of postural and locomotor control systems is required. Recent studies in nonhuman primates and other quadrupedal animals such as cats have clearly shown that there exist significant analogies between the primate species investigated (Macaco, mulatta, Macaca fascicularis, and marmosets) and the cats regarding the spinal stepping generator or central pattern generator (CPG), supraspinal descending pathways which activate CPG, and the midbrain and brain stem postural and locomotor control structures. Further studies aimed at elucidating the differences and similarities in the manner of locomotor control among different animal species will help us in understanding the control mechanisms involved in both bipedal and quadrupedal locomotor movements in nonhuman primates.

ISSN:0015-5713    

DOI:10.1159/000157194

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

For many decades, ablation experiments were used to evaluate the function of central nervous system structures in primates. The use of this technique has greatly diminished with the development of neuronal unit recording. Nevertheless, the available films and written descriptions from prior ablation studies can still be used to further our understanding of: (1) the functional organization of the primate brain; (2) the differences in function between similar cerebral structures in primates and other mammals, and (3) ontogenetic changes in the functional characteristics of cerebral structures. We are in the process of making some of the films and records from these prior studies available to interested scientists.

ISSN:0015-5713    

DOI:10.1159/000157195

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Kinetics and kinematics of the quadrupedal walking of Ateles and Macaca were studied, and the results were compared with those of vertical climbing. Macaca seems to use similar strategies for locomotion in climbing and walking horizontally, whereas Ateles apparently changes strategies. Next, volumetric comparisons of three cerebellar nuclei (M, I, L), the ventral pons (VP), the inferior olivary principal (Pr) and accessory (Ac) nuclei, and the vestibular nuclear complex (VES) were made by using size indices of each nucleus. Higher values are recognized clearly in the medial zone group (M, Ac, VES) of Macaca, whereas almost similar values are shown to exist in the lateral zone group (L, Pr, VP) of both species. Relationships between the kinesiological results and the development of the cerebellar system are discussed.

ISSN:0015-5713    

DOI:10.1159/000157196

出版商:S. Karger AG    

年代:1996

数据来源: Karger

摘要:

Interactions between locomotor, respiratory, and cardiac rhythms were investigated in human subjects (n = 11) walking on a treadmill. Investigation of the phase relationship between heart rate and gait signals revealed that cardiac rhythms were entrained to locomotor rhythms when both frequencies were close to an integer ratio. Coherence spectra were estimated between heartbeat fluctuation, respiratory, and gait signals, and their magnitudes were evaluated. The results suggest that the respiratory-induced fluctuation in heartbeat would vary depending on the strength of the cardiolocomotor coupling. The synchronization tends to occur for one or two specific phases in an individual subject, but there was some variation among subjects. When the subjects voluntarily synchronized their cadence with the cardiac rhythm, the heart rate and blood pressure varied depending on the phase lag within a cardiac cycle. The coordination of locomotor and cardiac rhythms is discussed.

ISSN:0015-5713    

DOI:10.1159/000157197

出版商:S. Karger AG    

年代:1996

数据来源: Karger