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1.
Bate M 《Current opinion in neurobiology》1999,9(6):670-675
The development of motor behaviour depends on the differentiation of underlying circuitry. Recent work with the zebrafish brings the simple swimming behaviour of lower vertebrates and their embryos into focus as a suitable model to study the development of motor circuitry and its genetic control. Changes in connectivity and excitability contribute to the development of swimming in this simple system. In the chick embryo, limb motor circuitry is spontaneously active before motor axons reach their muscle targets, and it has properties in common with the spontaneously active networks in the retina. The early rhythmic activity responsible for embryonic movement is probably a generalised property of developing spinal networks that precedes, and may be required for, the completion of functional locomotor circuitry. 相似文献
2.
Neuromodulation during motor development and behavior 总被引:3,自引:0,他引:3
Pflüger HJ 《Current opinion in neurobiology》1999,9(6):683-689
Important recent advances have been made in understanding the role of aminergic modulation during the maturation of Xenopus larvae swimming rhythms, including effects on particular ion channel types of component neurons, and the role of peptidergic modulation during development of adult central patterns generators in the stomatogastric ganglion of crustaceans. By recording from octopaminergic neuromodulatory neurons during ongoing motor behavior in the locust, new insights into the role of this peripheral neuromodulatory mechanism have been gained. In particular, it is now clear that the octopaminergic neuromodulatory system is automatically activated in parallel to the motor systems, and that both excitation and inhibition play important functional roles. 相似文献
3.
Forssberg H 《Current opinion in neurobiology》1999,9(6):676-682
It has been possible to expand considerably our understanding of human motor development by making a detailed analysis of various types of movement and muscular activation patterns during different stages of development. Alterations in development subsequent to the appearance of brain lesions have enabled valuable information to be collected about the underlying neural mechanisms, in addition to new information concerning the pathophysiology of cerebral palsy. Studies on the development of the corticospinal system indicate that plastic changes can take place after perinatal brain damage. 相似文献
4.
Mussa-Ivaldi FA 《Current opinion in neurobiology》1999,9(6):713-717
The study of complex motor behaviours has highlighted the role of modular representations both in the planning and in the execution of actions. Recent findings suggest the presence of functional modules within a variety of neural structures. Computational investigations are now addressing the issue of how these modules may act concurrently to generate a wide repertoire of behaviours. 相似文献
5.
Mental imaging of motor activity in humans 总被引:13,自引:0,他引:13
Motor imagery corresponds to a subliminal activation of the motor system, a system that appears to be involved not only in producing movements, but also in imagining actions, recognising tools and learning by observation, as well as in understanding the behaviour of other people. Recent advances in the field include the use of techniques for mapping brain activity and probing cortical excitability, as well as observation of brain lesioned patients during imaging tasks; these advances provide new insights into the covert aspects of motor activity. 相似文献
6.
Internal models for motor control and trajectory planning 总被引:36,自引:0,他引:36
Kawato M 《Current opinion in neurobiology》1999,9(6):718-727
A number of internal model concepts are now widespread in neuroscience and cognitive science. These concepts are supported by behavioral, neurophysiological, and imaging data; furthermore, these models have had their structures and functions revealed by such data. In particular, a specific theory on inverse dynamics model learning is directly supported by unit recordings from cerebellar Purkinje cells. Multiple paired forward inverse models describing how diverse objects and environments can be controlled and learned separately have recently been proposed. The 'minimum variance model' is another major recent advance in the computational theory of motor control. This model integrates two furiously disputed approaches on trajectory planning, strongly suggesting that both kinematic and dynamic internal models are utilized in movement planning and control. 相似文献
7.
Brain imaging techniques have demonstrated functional specialisation of multiple areas within the motor system. They have also defined the patterns of interactions between these regions during normal motor function and in motor disorders. Functional imaging makes visible the changes in cortical activity that take place over time during motor functions, from the activations a fraction of a second before voluntary action to cortical neuronal plasticity several weeks after injury. Recently, the functional abnormalities underlying various acquired and developmental motor disorders have been described, as well as the effects of therapeutic intervention. 相似文献
8.
In the past year, candidates have been identified for two long-sought classes of molecules, insect odorant receptors and mammalian taste receptors. In addition, genes directing receptor gene expression and the development of specific chemosensory neurons have been described in Drosophila melanogaster and Caenorhabditis elegans. Finally, recent physiological experiments have provided new insights into the mechanisms by which chemosensory information is processed. 相似文献
9.
Grillner S 《Current opinion in neurobiology》1999,9(6):663-669
A major challenge for current research in neuroscience is to understand the intrinsic operation of the functional modules of the central nervous system, such as those formed by cortical columns and the neuronal networks controlling motor behaviour. Most vertebrate experimental models used in network analyses involve developing nervous systems, which are in rapid transition with regard to their cellular properties and the expression of different ion channels. Recent advances in our understanding of the cellular and circuit properties of motor networks are making it possible to decipher the mechanisms involved in vertebrate motor pattern generation. 相似文献
10.
Sparks DL 《Current opinion in neurobiology》1999,9(6):698-707
Various conceptual issues have been brought into focus by recent experiments studying the role of the superior colliculus in the control of coordinated movements of the eyes and head, the interaction of saccadic and vergence movements, and cognitive processes influencing the initiation and execution of saccades. 相似文献
11.
In recent studies examining the modulation of dopamine (DA) cell firing patterns, particular emphasis has been placed on excitatory afferents from the prefrontal cortex and the subthalamic nucleus. A number of inconsistencies in recently published reports, however, do not support the contention that tonic activation of NMDA receptors is the sole determinate of DA neuronal firing patterns. The results of work on the basic mechanism of DA firing and the action of apamin suggest that excitatory projections to DA neurons from cholinergic and glutamatergic neurons in the tegmental pedunculopontine nucleus, and/or inhibitory GABAergic projections, are also involved in modulating DA neuron firing behavior. 相似文献
12.
Hypothalamic control of feeding 总被引:3,自引:0,他引:3
Our understanding of the hypothalamic control of energy homeostasis has increased greatly since the discovery of leptin, the adipose cell derived protein. Recent studies have identified several new hypothalamic neuropeptides that affect food intake and energy balance. By studying these molecules and their neuronal systems, receptors and interactions, we are beginning to unravel the circuitry between peripheral adipogenic signals and hypothalamic effector pathways. 相似文献
13.
Recent psychophysical studies on normal subjects, as well as brain imaging studies, have revised the concepts concerning the mechanisms underlying spatial orientation during navigation tasks. The emphasis has been put on internal models that allow the prediction of a planned trajectory and are essential in the steering of locomotion. Cognitive factors such as strategies and emotional parameters are now starting to be included in the research on spatial orientation. It is obvious that important individual and gender differences exist in the brain operations underlying spatial orientation in humans, which may help to understand the construction of a coherent perception and the organic neural disorders related to the internal representation of space. 相似文献
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15.
Goodwin SF 《Current opinion in neurobiology》1999,9(6):759-765
Sex and death. Two things that come once in a lifetime. Only after death you're not nauseous. - Woody Allen 'Sleeper'. The brain and nervous system functions that underlie sex-specific behaviour are of obvious importance to all animals, including humans. To understand behaviour related to sex, it is important to distinguish those aspects that are controlled genetically. Much of the recent progress in studies of the molecular neurogenetics of sexual differentiation and behaviour has come from the use of genetically tractable organisms (i.e. fruitflies and nematode worms) that exhibit a full range of sexually dimorphic phenotypes. 相似文献
16.
James Ashe Abdel El Manira Bambos Kyriacou Stephen F Goodwin Andrew Lumsden Susan Chapman Stefan Jungbluth Esther Bell Ana Coutinho Moheb Costandi Niels Adams Renee Dutton Mark Mayford Barbara Knowlton Michael Husser Venkatesh N Murthy John N Wood John A Assad Morgan Sheng Marie T Filbin Jin Qiu Eugene P Brandon Fred H Gage 《Current opinion in neurobiology》1999,9(6):645
A selection of interesting papers that were published in the two months before our press date in major journals most likely to report significant results in neurobiology. 相似文献
17.
Neurobiology of sexual behavior 总被引:4,自引:0,他引:4
Pfaus JG 《Current opinion in neurobiology》1999,9(6):751-758
Recent advances in the neurobiology of sexual behavior have helped to refine our understanding of the neuroanatomical, neuroendocrine and neurochemical systems that modulate responses to sexual stimulation. Both appetitive and consummatory sexual behaviors have been studied in several laboratory species and in humans using traditional and novel behavioral paradigms. New knowledge has emerged concerning the role of hypothalamic, limbic and brainstem structures, neuropeptides, brain monoamines and nitric oxide in the control of partner preference, sexual desire, erection, copulation, ejaculation, orgasm and sexual satiety. Brain imaging of visually evoked sexual arousal in humans has also been examined. 相似文献
18.
A selection of World Wide Web sites relevant to the reviews published in this issue of Current Opinion in Neurobiology. 相似文献
19.
When different cone snail peptides are injected into the CNS of vertebrates, they elicit diverse behaviors primarily because of their selectivity for specific receptor or ion channel subtypes. The subcellular context of the highly localized targets (i.e. the presence of other cellular elements that are functionally linked to the targets of conopeptides) is another determinant of the elicited behavior. Recent studies have advanced our understanding of the mechanisms by which four conopeptides produce different behaviors in mice. 相似文献
20.
Brain development: Integrins and the Reelin pathway 总被引:4,自引:0,他引:4
Integrins link the extracellular matrix to the intracellular environment. They have been implicated in the Reelin pathway in cortical development. But new genetic studies have revealed that, while beta(1) integrin plays a role in formation of the basement membrane, it is not essential for neuronal migration. 相似文献