Showing papers in "Current Opinion in Neurobiology in 1999"

TL;DR: The 'minimum variance model' is another major recent advance in the computational theory of motor control, strongly suggesting that both kinematic and dynamic internal models are utilized in movement planning and control.

TL;DR: Findings suggest that changes in mother-offspring interactions and central corticotropin-releasing factor systems are a critical target for the effects of variations in maternal care.

TL;DR: High-resolution measurements of [Ca2+]i in dendritic spines show how Ca2+ can encode the precise relative timing of presynaptic input and postsynaptic activity and generate long-term synaptic modifications of opposite polarity.

TL;DR: This work has shown that multiple second messengers, such as cyclic adenosine monophosphate, protein kinase A, calcium, and diacylglycerol, can control ERK signalling via the small G proteins Ras and Rap1, and allows us to begin to develop a model to understand both the control of ERKs at the subcellular level and the generation ofERK signal specificity.

TL;DR: 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.

TL;DR: Dendritic spines are distinguished by their shapes, subcellular composition, and synaptic receptor subtypes and can form without synaptic activation, are maintained by optimal activation, and are lost with excessive activation or during degeneration.

TL;DR: Many diffusible axon guidance cues and their receptors have been identified recently and are often found to be bifunctional, acting as attractants or repellents under different circumstances.

TL;DR: Over the past year, evidence has accrued that adult CNS stem cells are a widespread progenitor cell type and the fate of stem cell progeny in vivo may be linked to the complexity of the animal's environment.

TL;DR: This work has shown that the high excitability of recurrently connected, developing networks and the presence of activity-induced transient depression of network excitability in the spinal cord is of particular importance for spontaneous, periodic activity in mice.

TL;DR: Specialized functions proposed for the hippocampus in contextual learning include the construction and consolidation of contextual memory representations, incidental contextual learning, and inhibitory contextual learning.

TL;DR: The belt and parabelt regions appear to be concerned with integrative and associative functions involved in pattern perception and object recognition and connect with regions of temporal, parietal, and frontal cortex that mediate additional auditory functions, including space perception and auditory memory.

TL;DR: Experiments suggest that cholinergic neurons serve a modulatory function in cognition, by optimizing cortical information processing and influencing attention.

TL;DR: Ephrins appear to act typically, but not exclusively, as repellents throughout development to influence axon pathfinding and topographic mapping, as well as restricting cell migration and intermingling.

TL;DR: Functional brain imaging, combined with the use of virtual environments, has revealed strong parallels between humans and other animals in the neural basis of navigation.

TL;DR: The circuitry mediating the integration of reward perception and adaptive behavioral responses has been further refined and indicates that the nucleus accumbens has a primary role in motivational circuitry, whereas afferents to the nucleus Accumbens, in part, subserve distinct functions.

TL;DR: Studies of the role of the basic helix-loop-helix genes in retinal development have indicated that they can regulate competence and/or other aspects of cell fate determination.

TL;DR: Quantitative analysis of as many as eight distinct molecular mechanisms may be involved in rod photoreceptor light adaptation is providing new insights into the nature of rod Photorecept light adaptation.

TL;DR: Neuroimaging methods have been used to characterize the circuitry underlying disorders of emotion and particular emphasis has been placed on the prefrontal cortex, anterior cingulate, parietal cortex, and the amygdala as critical components of the circuitry that may be dysfunctional in both depression and anxiety.

TL;DR: New research has highlighted the enormous range of neurotrophin actions at both developing and mature synapses, demonstrating that transmission can be enhanced or reduced at excitatory and inhibitory synapses by either pre- or postsynaptic mechanisms.

TL;DR: Experiments using two-photon microscopy suggest that the concentration of glutamate in the synaptic cleft does not attain levels previously suggested, and recordings from glial cells and studies of extrasynaptic receptor activation indicate that significant quantities of glutamate escape from the cleft following exocytosis.

TL;DR: 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.

TL;DR: The early specification of dopaminergic and serotonergic neurons during vertebrate CNS development relies on signals produced by a small number of organizing centers, which define the manner in which they may be established, the inductive signals they produce, and candidate signaling systems that control the later development of the dopamine system.

TL;DR: Until recently, the neural bases underlying recovery of function after damage to the cerebral cortex were largely unknown, but results from neuroanatomical and neurophysiological studies in animal models have demonstrated that after cortical damage, long-term and widespread structural and functional alterations take place in the spared cortical tissue.

TL;DR: Analysis of axon guidance mechanisms in vertebrates, Caenorhabditis elegans, and Drosophila melanogaster has led to the identification of several signaling pathways, many of which are strikingly conserved in function.

TL;DR: There is a case to be made for homology among members of the two great protostome clades (the ecdysozoans and lophotrochozoans), but the position of the craniates remains ambiguous.

TL;DR: An emerging view of synaptic plasticity suggests that local neurotrophin action and synaptically associated protein synthesis may promote synaptic remodelling and changes in receptor expression or activation.

TL;DR: The use of a new antagonist (LY341495) that blocks all known metabotropic L-glutamate receptors in the brain, together with subtype-selective antagonists, has identified multiple roles both for cloned and novel glutamate receptors in hippocampal long-term potentiation and long- term depression.

TL;DR: Mouse studies have shown that axonal neurofilaments are not required for pathogenesis caused by mutations in superoxide dismutase and that increasing perikaryal levels of neurofilament proteins may even confer protection in this disease.

TL;DR: 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.

TL;DR: 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 ofSaccades.