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The potential of neuroimage databases to accelerate the dissemination and use of information about brain structure and function is enormous and ever increasing. Numerous efforts are now underway to further develop the technology and sociology that are necessary to support this revolution. Each effort has its own approach and tackles some of the complex problems that are associated with creating and providing access to a database. This paper introduces many of the recent successes and future challenges that are faced by the developers and users of neuroimage databases. [ABSTRACT FROM AUTHOR]

The article reports on a study conducted by T. Goldmann and colleagues, which reveals the potential of a new type of microglia gene targeting in central nervous system (CNS) autoimmune inflammation.

Reports on three studies that provide insights into the encoding of spatial information by the hippocampus and entorhinal cortex. Importance of the entorhinal cortex in providing spatial information to the hippocampus; Differences between hippocampal subfields; Roles of local landmarks and background context in modulating CA1 and CA3 activity.

Discusses a study which examined the metabolism of neurotransmitter and its effect on the filling of synaptic vesicles. Production of the inhibitory transmitter aminobutyric acid (GABA); Method used to increase or decrease the presynaptic GABA content of interneurons in cultured hippocampal slices; Reliability of quantal analysis in the central nervous system.

Discusses research being done on the glutamate release at synapses in the calyx of Held, a rat brainstem. Reference to a study by J. Y. Sun and L. G. Wu, published in the 2001 issue of the journal "Neuron"; Discussion on the information processing in the central nervous system; Capabilities of conventional central synapses.

Presents an abstract of several articles on neuroscience, published in several scientific journals. "LIS1 regulates CNS lamination by interfacing with mNudE, a central component of the centrosome," by Feng, Y. et al; "Mutations in GFAP, encoding glial fibrillary acidic protein, are associated with Alexander disease," by Brenner, M. et al; "A global geometric framework on nonlinear dimensionality reduction," by Tenenbaum, J.B. et al.

Discusses research being done on whether the transcription factor Phox2b which is known to participate in the differentiation of motor neurons can also induce their precursors to stop dividing. Reference to study by V. Dubreuil et al, published in a 2000 issue of the journal "Development"; Effect of Phox2b misexpression on the number of cells expressing early markers of postmitotic precursors; Potential mechanism behind the influence of Phox2b in motor neuron generation.

Pathological perturbations of the brain are rarely confined to a single locus; instead, they often spread via axonal pathways to influence other regions. Patterns of such disease propagation are constrained by the extraordinarily complex, yet highly organized, topology of the underlying neural architecture; the so-called connectome. Thus, network organization fundamentally influences brain disease, and a connectomic approach grounded in network science is integral to understanding neuropathology. Here, we consider how brain-network topology shapes neural responses to damage, highlighting key maladaptive processes (such as diaschisis, transneuronal degeneration and dedifferentiation), and the resources (including degeneracy and reserve) and processes (such as compensation) that enable adaptation. We then show how knowledge of network topology allows us not only to describe pathological processes but also to generate predictive models of the spread and functional consequences of brain disease. [ABSTRACT FROM AUTHOR]

All cells use changes in intracellular calcium concentration ([Ca2+]i) to regulate cell signalling events. In neurons, with their elaborate dendritic and axonal arborizations, there are clear examples of both localized and widespread Ca2+ signals. [Ca2+]i changes that are generated by Ca2+ entry through voltage- and ligand-gated channels are the best characterized. In addition, the release of Ca2+ from intracellular stores can result in increased [Ca2+]i; the signals that trigger this release have been less well-studied, in part because they are not usually associated with specific changes in membrane potential. However, recent experiments have revealed dramatic widespread Ca2+ waves and localized spark-like events, particularly in dendrites. Here we review emerging data on the nature of these signals and their functions. [ABSTRACT FROM AUTHOR]

The article investigates neuronal migration in the human brain using rodent models. Throughout the postnatal life of rodents, neural progenitor cells migrate from the subventricular zone (SVZ) of the forebrain through the rostral migratory system (RMS) to the olfactory bulb. Although humans also have an SVZ, until now the existence of an RMS had not been demonstrated. In this article, the researchers described evidence of a well-defined RMS in the human brain.

Chronic fatigue syndrome (CFS) is a debilitating illness that affects many people. It has been marred by controversy, from initial scepticism in the medical community about the existence of the condition itself to continuing disagreements--mainly between some patient advocacy groups on one side, and researchers and physicians on the other--about the name for the illness, its aetiology, its pathophysiology and the effectiveness of the few currently available treatments. The role of the CNS in the disease is central in many of these discussions. Nature Reviews Neuroscience asked four scientists involved in CFS research about their views on the condition, its causes and the future of research aimed at improving our understanding of this chronic illness. [ABSTRACT FROM AUTHOR]

The article discusses research being done on the role of the spinal cord roof plate in regulating cell type specification and proliferation during development of the cerebellar anlage. It references a study by V. V. Chizhikov et al in a 2006 issue of "Development." It offers insights into the complex processes of cerebellar development. Information about the comprehensive molecular map of the entire early cerebellar anlage provides a useful tool for explaining the intricacies of cerebellar development.

Parkinson's disease, like many common age-related conditions, is now recognized to have a substantial genetic component. Here, I discuss how mutations in a large complex gene--leucine-rich repeat kinase 2 (LRRK2)--affect protein function, and I review recent evidence that LRRK2 mutations affect pathways that involve other proteins that have been implicated in Parkinson's disease, specifically α-synuclein and tau. These concepts can be used to understand disease processes and to develop therapeutic opportunities for the treatment of Parkinson's disease. [ABSTRACT FROM AUTHOR]

Long-term depression (LTD) in the CNS has been the subject of intense investigation as a process that may be involved in learning and memory and in various pathological conditions. Several mechanistically distinct forms of this type of synaptic plasticity have been identified and their molecular mechanisms are starting to be unravelled. Most studies have focused on forms of LTD that are triggered by synaptic activation of either NMDARs (N-methyl-D-aspartate receptors) or metabotropic glutamate receptors (mGluRs). Converging evidence supports a crucial role of LTD in some types of learning and memory and in situations in which cognitive demands require a flexible response. In addition, LTD may underlie the cognitive effects of acute stress, the addictive potential of some drugs of abuse and the elimination of synapses in neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

Presents the results of a study on the contribution of gene evolution to the development of the brain. Comparison of the rates of evolution of genes in the primate lineage and non-primate lineage; Factors that influenced the role of genes in nervous system function; Details of the developmental process involved in evolutionary changes in brain size.

Neurons and glial cells show mutual interdependence in many developmental and functional aspects of their biology. To establish their intricate relationships with neurons, glial cells must migrate over what are often long distances. In the CNS glial cells generally migrate as single cells, whereas PNS glial cells tend to migrate as cohorts of cells. How are their journeys initiated and directed, and what stops the migratory phase once glial cells are aligned with their neuronal counterparts? A deeper understanding of glial migration and the underlying neuron–glia interactions may contribute to the development of therapeutics for demyelinating diseases or glial tumours. [ABSTRACT FROM AUTHOR]

The past few years have witnessed dramatic progress on all frontiers of zinc neurobiology. The recent development of powerful tools, including zinc-sensitive fluorescent probes, selective chelators and genetically modified animal models, has brought a deeper understanding of the roles of this cation as a crucial intra- and intercellular signalling ion of the CNS, and hence of the neurophysiological importance of zinc-dependent pathways and the injurious effects of zinc dyshomeostasis. The development of some innovative therapeutic strategies is aimed at controlling and preventing the damaging effects of this cation in neurological conditions such as stroke and Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Brain banks collect post-mortem human brains to foster research into human CNS function and disease. They have been indispensable for uncovering the secrets of many diseases, including Alzheimer's and Parkinson's. At a time when there are so many open questions in neuroscience and the incidence of brain diseases continues to increase in parallel with the aging of the population, brain banking remains at the heart of brain research. However, the major source of brain banks, the clinical autopsy, is rapidly falling into limbo. New strategies, including donor programmes, medico-legal autopsies and banking in networks, as well as fresh considerations of the ethics and public relations, are required. [ABSTRACT FROM AUTHOR]

Reports on a study about how the different areas of the brain that have been implicated in attentional process might interact, published in the periodical "Proceedings of the National Academy of Sciences." Methods used; Level of activity in the beta frequency band; Connection of brain areas into a functional network.

Discusses various parallels that can be drawn between axon guidance mechanisms in flies and vertebrates. Significance of the interaction between the Slit repellents and the Roundabout family of receptors for guiding axons across central nervous system midline in Drosophila melanogaster; Information on the two populations of interneurons recognized in the vertebrate central nervous system.

Over the past decade or so, CART (cocaine- and amphetamine-regulated transcript) peptides have emerged as major neurotransmitters and hormones. CART peptides are widely distributed in the CNS and are involved in regulating many processes, including food intake and the maintenance of body weight, reward and endocrine functions. Recent studies have produced a wealth of information about the location, regulation, processing and functions of CART peptides, but additional studies aimed at elucidating the physiological effects of the peptides and at characterizing the CART receptor(s) are needed to take advantage of possible therapeutic applications. [ABSTRACT FROM AUTHOR]

Our movements can hinder our ability to sense the world. Movements can induce sensory input (for example, when you hit something) that is indistinguishable from the input that is caused by external agents (for example, when something hits you). It is critical for nervous systems to be able to differentiate between these two scenarios. A ubiquitous strategy is to route copies of movement commands to sensory structures. These signals, which are referred to as corollary discharge (CD), influence sensory processing in myriad ways. Here we review the CD circuits that have been uncovered by neurophysiological studies and suggest a functional taxonomic classification of CD across the animal kingdom. This broad understanding of CD circuits lays the groundwork for more challenging studies that combine neurophysiology and psychophysics to probe the role of CD in perception. [ABSTRACT FROM AUTHOR]

Higher-order actin-based networks (actin superstructures) are important for growth-cone motility and guidance. Principles for generating, organizing and remodelling actin superstructures have emerged from recent findings in cell-free systems, non-neuronal cells and growth cones. This Review examines how actin superstructures are initiated de novo at the leading-edge membrane and how the spontaneous organization of actin superstructures is driven by ensembles of actin-binding proteins. How the regulation of actin-binding proteins can affect growth-cone turning and axonal regeneration is also discussed. [ABSTRACT FROM AUTHOR]

Discusses the study 'Robo and Frazzled/DCC Mediate Dendritic Guidance at the CNS Midline,' by M.-P. Furrer et al., from a 2003 issue of 'Nature Neuroscience.' Information on the central nervous system of Drosophila; Mechanism of action of the mutants; Interpretation of the findings.

Post-translational protein modifications are integral components of signalling cascades that enable cells to efficiently, rapidly and reversibly respond to extracellular stimuli. These modifications have crucial roles in the CNS, where the communication between neurons is particularly complex. SUMOylation is a post-translational modification in which a member of the small ubiquitin-like modifier (SUMO) family of proteins is conjugated to lysine residues in target proteins. It is well established that SUMOylation controls many aspects of nuclear function, but it is now clear that it is also a key determinant in many extranuclear neuronal processes, and it has also been implicated in a wide range of neuropathological conditions. [ABSTRACT FROM AUTHOR]

At the end of the 1980s, it was clearly demonstrated that cells produce nitric oxide and that this gaseous molecule is involved in the regulation of the cardiovascular, immune and nervous systems, rather than simply being a toxic pollutant. In the CNS, nitric oxide has an array of functions, such as the regulation of synaptic plasticity, the sleep–wake cycle and hormone secretion. Particularly interesting is the role of nitric oxide as a Janus molecule in the cell death or survival mechanisms in brain cells. In fact, physiological amounts of this gas are neuroprotective, whereas higher concentrations are clearly neurotoxic. [ABSTRACT FROM AUTHOR]

A rapidly growing number of recent studies show that imagining the future depends on much of the same neural machinery that is needed for remembering the past. These findings have led to the concept of the prospective brain; an idea that a crucial function of the brain is to use stored information to imagine, simulate and predict possible future events. We suggest that processes such as memory can be productively re-conceptualized in light of this idea. [ABSTRACT FROM AUTHOR]

The majority of functional neuroscience studies have focused on the brain's response to a task or stimulus. However, the brain is very active even in the absence of explicit input or output. In this Article we review recent studies examining spontaneous fluctuations in the blood oxygen level dependent (BOLD) signal of functional magnetic resonance imaging as a potentially important and revealing manifestation of spontaneous neuronal activity. Although several challenges remain, these studies have provided insight into the intrinsic functional architecture of the brain, variability in behaviour and potential physiological correlates of neurological and psychiatric disease. [ABSTRACT FROM AUTHOR]

Advances in our understanding of the mechanisms of tau-mediated neurodegeneration in Alzheimer's disease (AD) and related tauopathies, which are characterized by prominent CNS accumulations of fibrillar tau inclusions, are rapidly moving this previously underexplored disease pathway to centre stage for disease-modifying drug discovery efforts. However, controversies abound concerning whether or not the deleterious effects of tau pathologies result from toxic gains-of-function by pathological tau or from critical losses of normal tau function in the disease state. This Review summarizes the most recent advances in our knowledge of the mechanisms of tau-mediated neurodegeneration to forge an integrated concept of those tau-linked disease processes that drive the onset and progression of AD and related tauopathies. [ABSTRACT FROM AUTHOR]

Activity-dependent changes in the strength of excitatory synapses are a cellular mechanism for the plasticity of neuronal networks that is widely recognized to underlie cognitive functions such as learning and memory. AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid)-type glutamate receptors (AMPARs) are the main transducers of rapid excitatory transmission in the mammalian CNS, and recent discoveries indicate that the mechanisms which regulate AMPARs are more complex than previously thought. This review focuses on recent evidence that alterations to AMPAR functional properties are coupled to their trafficking, cytoskeletal dynamics and local protein synthesis. These relationships offer new insights into the regulation of AMPARs and synaptic strength by cellular signalling. [ABSTRACT FROM AUTHOR]

Deals with the solution to the difficulty in the repair of the regenerative capacity of axons in the central nervous system (CNS). Characteristics of the primary sensory neurons of the dorsal root ganglion neurons; Factor that allows CNS neurons to grow on myelin; Impact of the presence of a cyclic AMP on a peripheral lesion.

Discusses research on the role of transcription factor Lbx1 in distinguishing neuronal subtypes. Reference to studies which appeared in "Neuron" journal; Information on neuronal progenitors from the dorsal spinal cord; Function of Lbx1 in dorsal interneuron specification.

Discusses a study which examined the importance of astrocytes in promoting neuronal differentiation. Extraction of stem cells from the adult rat hippocampus; Effects of astrocytes; Role of astrocytes in the central nervous system.

Discusses research being done on the functional recovery after injury to the spinal cord. Reference to a study by Y. D. Teng et al, published in the 2002 issue of the "Proceedings of the National Academy of Sciences"; Implantation of biodegradable scaffolds into the injured region; Potential of a polymer scaffold seeded with neural stem cells in the recovery of the spinal cord.

Discusses research being done on oligodendrocytes, the myelinating cells of the central nervous system. Reference to a study by H. Fu et al, published in the 2002 issue of the "Development" journal; Origin of oligodendrocytes; Description of the dorsoventral axis of the developing spinal cord.

Dorsoventral patterning of the neural tube has a crucial role in shaping the functional organization of the CNS. It is well established that hedgehog signalling plays a key role in specifying ventral cell types throughout the neuroectoderm, and major progress has been made in elucidating how hedgehog signalling works in this ventral specification. In addition, other molecular pathways, including nodal, retinoic acid and fibroblast growth factor signalling, have been identified as important molecular cues for ventral patterning of the spinal cord, telencephalon and eye. Here, we discuss recent advances in this field, highlighting the emerging interplay of these signalling pathways in the molecular specification of ventral patterning at different rostrocaudal levels of the CNS. [ABSTRACT FROM AUTHOR]

Focuses on the association of many neurodegenerative diseases with the excessive deposition of iron in the regions of the brain that undergo degeneration. Cause of such deposition; Diseases that are characterized by a build-up of iron in the basal ganglia; Event that interferes with the stability of the ferritin molecule.

Focuses on the importance of electrical synapses for brain function. Way in which electrical synapses are formed; Existence of such synapses in the retina; Cells involved in the formation of such synapses.

Discusses research being done on segmental patterns in the developing chick diencephalon. Reference to study by C. W. Larsen et al, published in the 2001 issue of "Journal of Neuroscience"; Subdivisions of the diencephalon; Physical features and properties of rhombomeres in the diencephalon; Key to the lineage restriction between rhombomeres.

Discusses research being done on the physiological aspects of pain. Reference to studies by J. P. Johansen et al, R. K. Hofbauer et al and J. K. Zubieta et al, published in the 2001 issues of "Proceedings of the National Academy of Sciences USA," "Journal of Neurophysiology" and "Science"; Importance of the anterior cingulate cortex for the conditioned place avoidance behavior of rats; Correlation of changes in pain intensity with activity in the primary somatosensory cortex; Function of µ-opioid receptors during sustained pain.

Discusses research being done on the importance of fibroblast growth factor receptor signaling in the maintenance of neural progenitors during Henson's development. Reference to a study by L. Mathis et al., published in the 2001 issue of the journal "Nature Cell Biology"; Significance of the precise coordination of cell movement and growth during development; Development process of spinal cord progenitor cells.

Discusses research on the difference in signals for axon growth during central nervous system development and regeneration. Reference to a study by A.J. Udvadia et al., published in a 2001 issue of the journal "Development"; Mechanism of action of GAP-43 promoter; Indications of the research findings.

Discusses research being done on the baseline state of the brain. Reference to study by Marcus Raichle and colleagues, published in the 2001 issue of "Proceedings of the National Academy of Sciences USA"; Key to measuring a variety of metabolic and circulatory relationships between blood flow and oxygen consumption in the brain; Correlation of the oxygen extraction fraction with brain activity.

Describes the study conducted by Laura Petitto, Robert Zatorre, et. al. on the neural basis of sign language organization in deaf subjects. Brain processing of speech-based language; Observation of cerebral blood flow activity of the subjects; Areas of the brain involved in sign language processing.

Mitochondrial uncoupling mediated by uncoupling protein 1 (UCP1) is classically associated with non-shivering thermogenesis by brown fat. Recent evidence indicates that UCP family proteins are also present in selected neurons. Unlike UCP1, these proteins (UCP2, UCP4 and BMCP1/UCP5) are not constitutive uncouplers and are not crucial for non-shivering thermogenesis. However, they can be activated by free radicals and free fatty acids, and their activity has a profound influence on neuronal function. By regulating mitochondrial biogenesis, calcium flux, free radical production and local temperature, neuronal UCPs can directly influence neurotransmission, synaptic plasticity and neurodegenerative processes. Insights into the regulation and function of these proteins offer unsuspected avenues for a better understanding of synaptic transmission and neurodegeneration. [ABSTRACT FROM AUTHOR]

Hedonic experience is arguably at the heart of what makes us human. In recent neuroimaging studies of the cortical networks that mediate hedonic experience in the human brain, the orbitofrontal cortex has emerged as the strongest candidate for linking food and other types of reward to hedonic experience. The orbitofrontal cortex is among the least understood regions of the human brain, but has been proposed to be involved in sensory integration, in representing the affective value of reinforcers, and in decision making and expectation. Here, the functional neuroanatomy of the human orbitofrontal cortex is described and a new integrated model of its functions proposed, including a possible role in the mediation of hedonic experience. [ABSTRACT FROM AUTHOR]

One of the key organizers in the CNS is the floor plate - a group of cells that is responsible for instructing neural cells to acquire distinctive fates, and that has an important role in establishing the elaborate neuronal networks that underlie the function of the brain and spinal cord. In recent years, considerable controversy has arisen over the mechanism by which floor plate cells form. Here, we describe recent evidence that indicates that discrete populations of floor plate cells, with characteristic molecular properties, form in different regions of the neuraxis, and we discuss data that imply that the mode of floor plate induction varies along the anteroposterior axis. [ABSTRACT FROM AUTHOR]

Two groups of hereditary ataxias are most relevant to humans - the autosomal recessive ataxias and the autosomal dominant spinocerebellar ataxias. Recessive ataxias are multisystem disorders that are characterized by inactivating mutations that result in loss of protein function. By contrast, cell death associated with dominant spinocerebellar ataxias is mostly restricted to the CNS, and cellular control of protein folding and processing is affected. The purpose of this review is to provide an integrated view of the field, encompassing the similarities - which are few - and the differences - which are many - between pathological processes that cause ataxia. In reviewing the current knowledge of ataxias, we discuss recent insights into the pathogenic mechanisms that lead to specific neuronal dysfunction and neurodegeneration. [ABSTRACT FROM AUTHOR]

The evolutionary emergence of the bilateral body plan and the central nervous system required the establishment of a midline organizer. The formation of a solitary, elongated but narrow organizing region for the dorsoventral (or mediolateral) axis requires rather complex molecular interactions. Different modes of midline formation evolved in vertebrates, insects and planarians, indicating that midline formation had a crucial role in the diversification of higher organisms. [ABSTRACT FROM AUTHOR]

In the central nervous system, synaptic strength is regulated partly by changes in the function and number of postsynaptic glutamate receptors. The NMDA (N-methyl-D-aspartate) subtype of glutamate receptor (NMDAR) is regulated in part by the opposing actions of protein tyrosine kinases and phosphotyrosine phosphatases. Members of the Src family of protein tyrosine kinases upregulate NMDAR function, thereby gating the production of NMDAR-dependent synaptic potentiation. Src family kinases (SFKs) are a crucial point of convergence for signalling pathways that enhance NMDAR activity, so that SFKs act as a molecular hub for the control of NMDARs. These kinases regulate synaptic strength and are therefore vital for processes that underlie physiological and pathological plasticity in the brain and spinal cord. [ABSTRACT FROM AUTHOR]