ganglia also play a critical role in sensorimotor function. Furthermore, the basal ganglia are prominently working hypothesis is that abnormal plasticity in the basal ganglia is a critical link between . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 559 Basal ganglia network

Synaptic plasticity is the ability of synaptic connections between neurons to be strengthened or weakened; a process that is central to the information processing within the brain and which plays a particularly important role in enabling higher cognitive processes [1,2]. Its role in disease is becoming increasingly clear across a wide ...

Accumulating evidence reveals that synaptic dysfunction precedes neuronal loss in neurodegenerative diseases such as Alzheimer's disease. Intriguingly, synaptic abnormality is also implicated in a myriad of psychiatric disorders including depression. In particular, alterations in spine density and morphology have been associated with ...

Professor Jeff Lichtman examines the concept of synaptic plasticity, a term that refers to the way the brain changes.

Professor Graham Collingridge explains that synaptic plasticity is the way most information is stored in the central nervous system.

Professor Tom O'Dell discusses synaptic plasticity - the strengthening and weakening of synaptic connections between neurons.

... S. TYPE OF REPORT A PERIOO COVERED E Theory of Synaptic Plasticity in Visual Cortex ... Page 2. Theory of Synaptic Plasticity in Visual Cortex* ...

Synaptic plasticity provides a record of neuronal activity and is a likely basis for memory. In this review, we discuss the current state of understanding of synaptic plasticity in terms of models and experiments.

Dystonia is a functionally disabling movement disorder characterized by abnormal movements and postures. Although substantial recent progress has been made in identifying genetic factors, the pathophysiology of the disease remains a mystery. A provocative suggestion gaining broader acceptance is that some aspect of neural plasticity may be ...

Work over the past two decades lead to substantial changes in our understanding of dystonia, which was, until recently, considered an exclusively sporadic movement disorder. The discovery of several gene mutations responsible for many inherited forms of dystonia has prompted much effort in the generation of transgenic mouse models bearing mutations found in patients. The large majority of these ...

The salient neuropathological defect in fragile X syndrome is the overabundance of immature dendritic spines in cortical pyramidal neurons. This review examines this anatomical synaptic defect in the context of other alterations in synaptic and circuit plasticity in fragile X mice. In theory, abnormal spines could ...

... Accession Number : ADA236223. Title : Synaptic Plasticity in Visual Cortex: Comparison of Theory with Experiment. Corporate ...

... and agencies for Research Development Test and ... Synaptic Plasticity in the Brain: Relationships to ... overview of these developments, considers the ...

... A Study of Neuronal Properties, Synaptic Plasticity and Network Interactions Using a Computer Reconstituted Neuronal Network Derived from ...

... A Study of Neuronal Properties, Synaptic Plasticity and Network Interactions Using a Computer Reconstituted Neuronal Network Derived from ...

role of inhibitory synaptic plasticity remains much more speculative. As with excitatory plasticity, inhibitory plasticity is likely to play multiple roles both in maintaining the proper homeostatic balanceNeuron Article Differential Effects of Excitatory and Inhibitory Plasticity on ...

Higher cerebral functions are based upon a dynamic organization of neuronal networks. To form synaptic connections and to continuously re-shape them in a process of ongoing structural adaptation, neurons must permanently withdraw from the cell cycle. In other words, synaptic plasticity can only occur on the expense of the ability to ...

Neuronal synaptic functional deficits are linked to impaired learning and memory in Alzheimer's disease (AD). We recently demonstrated that O-GlcNAc, a novel cytosolic and nuclear carbohydrate post-translational modification, is enriched at neuronal synapses and positively regulates synaptic plasticity linked to learning and memory in ...

There is mounting evidence showing that the structural and molecular organization of synaptic connections is affected both in human patients and in animal models of neurological and psychiatric diseases. As a consequence of these experimental observations, it has been introduced the concept of synapsopathies, a notion describing brain disorders of synaptic ...

Fragile X Syndrome (FXS) is the most common heritable cause of intellectual disability. In vitro electrophysiologic data from mouse models of FXS suggest that loss of fragile X mental retardation protein affects intracortical excitability and synaptic plasticity. Specifically, the cortex appears hyperexcitable, and use-dependent long-term potentiation ...

Manipulations of the actin-capping protein adducin in Drosophila and mammalian neurons provide new insights into the mechanisms linking structural changes to synaptic plasticity and learning. Adducin regulates synaptic remodeling, providing a molecular switch that controls synaptic growth versus disassembly during ...

Sensory experience, and the lack thereof, can alter the function of excitatory synapses in the primary sensory cortices. Recent evidence suggests that changes in sensory experience can regulate the synaptic level of Ca²⁺-permeable AMPA receptors (CP-AMPARs). However, the molecular mechanisms underlying such a process have not been determined. We found ...

A number of neuronal functions, including synaptic plasticity, depend on proper regulation of synaptic proteins, many of which can be rapidly regulated by phosphorylation. Neuronal activity controls the function of these synaptic proteins by exquisitely regulating the balance of various protein kinase and protein ...

It is clear that de novo protein synthesis has an important function in synaptic transmission and plasticity. A substantial amount of work has shown that mRNA translation in the hippocampus is spatially controlled and that dendritic protein synthesis is required for different forms of long-term synaptic plasticity. ...

Huntington's disease (HD) is a fatal hereditary neurodegenerative disease causing degeneration of striatal spiny neurons, whereas cholinergic interneurons are spared. This cell-type specific pathology produces an array of abnormalities including involuntary movements, cognitive impairments, and psychiatric disorders. Although the genetic mutation responsible for HD has been ...

The tectum opticum of fish midbrain is studied to demonstrate the involvement of gangliosides in the functional plastic changes in synaptic systems and in visual acuity. The structural synaptic plasticity after light variations involving synaptic vesicles...

Dendritic spines are small protrusions from neuronal dendrites that form the postsynaptic component of most excitatory synapses in the brain. They play critical roles in synaptic transmission and plasticity. Recent advances in imaging and molecular technologies reveal that spines are complex, dynamic structures that contain a dense array of cytoskeletal, ...

The aim of the present study was to evaluate the role of the nitric oxide/cyclic guanosine monophosphate pathway in corticostriatal long-term depression induction in a model of levodopa-induced dyskinesia in experimental parkinsonism. Moreover, we have also analysed the possibility of targeting striatal phosphodiesterases to reduce levodopa-induced dyskinesia. To study ...

B6-Tg/Thy1APP23Sdz (APP23) mutant mice exhibit neurohistological hallmarks of Alzheimer's disease but show intact basal hippocampal neurotransmission and synaptic plasticity. Here, we examine whether spatial learning differently modifies the structural and electrophysiological properties of hippocampal synapses in APP23 and wild-type mice. While no ...

Synaptically released Zn[superscript 2+] is a potential modulator of neurotransmission and synaptic plasticity in fear-conditioning pathways. Zinc transporter 3 (ZnT3) knock-out (KO) mice are well suited to test the role of zinc in learned fear, because ZnT3 is colocalized with synaptic zinc, responsible for its ...

A short account is given of the theory of synaptic plasticity: assumptions, consequences, comparison with experiment and statistical properties. In addition a framework for comparison with other theoretical ideas is presented.... Visual Theory, BCM Theory...

Recently, the striatum has been implicated in the spread of epileptic seizures. As the absence of functional scaffolding protein Bassoon in mutant mice is associated with the development of pronounced spontaneous seizures, we utilized this new genetic model of epilepsy to investigate seizure-induced changes in striatal synaptic plasticity. Mutant mice ...

Reelin, a large glycoprotein secreted by telencephalic GABAergic neurons, plays an important role in neuronal guidance embryonically and in synaptic plasticity postnatally. The reeler heterozygous mouse (+/rl) appears superficially normal but has been of interest as an animal model for psychosis since the discovery that reelin is 50% down-regulated in ...

Experiences, whether they be learning in a classroom, a stressful event, or ingestion of a psychoactive substance, impact the brain by modifying the activity and organization of specific neural circuitry. A major mechanism by which the neural activity generated by an experience modifies brain function is via modifications of synaptic transmission; that is, ...

Mutations in MECP2 underlie the neurodevelopmental disorder Rett syndrome (RTT). One hallmark of RTT is relatively normal development followed by a later onset of symptoms. Growing evidence suggests an etiology of disrupted synaptic function, yet it is unclear how these abnormalities explain the clinical presentation of RTT. Here we investigate synapse ...

Alzheimer's disease (AD) is characterized by cognitive impairment, progressive neurodegeneration and formation of amyloid-? (A?)-containing plaques and neurofibrillary tangles composed of hyperphosphorylated tau. The neurodegenerative process in AD is initially characterized by synaptic damage accompanied by neuronal loss. In addition, recent evidence suggests that alterations ...

Brain-derived neurotrophic factor (BDNF) is a prototypic neurotrophin that regulates diverse developmental events from the selection of neural progenitors to the terminal dendritic differentiation and connectivity of neurons. We focus here on activity-dependent synaptic regulation by BDNF and its receptor, full length TrkB. BDNF-TrkB signaling is involved in transcription, ...

Recent studies have suggested that schizophrenia is associated with alterations in the synaptic connectivity involving cytoskeletal proteins. The microtubule-associated protein STOP (Stable Tubule Only Polypeptide) plays a key-role in neuronal architecture and synaptic ...

... Descriptors : *MEMORY(PSYCHOLOGY), *VISUAL CORTEX, COMPARISON, THEORY, NAVAL RESEARCH, PLASTIC PROPERTIES, NERVE ...

We evaluated various forms of hippocampus-dependent learning and memory, and hippocampal synaptic plasticity in THY-Tau22 transgenic mice, a murine tauopathy model that expresses double-mutated 4-repeat human tau, and shows neuropathological tau hyperphosphorylation and aggregation throughout the brain. Focussing on hippocampus, immunohistochemical studies ...

Dnmt1 and Dnmt3a, two major DNA methyltransferases, are expressed in postmitotic neurons, but their function in the central nervous system (CNS) is unclear. We generated conditional mutant mice that lack either Dnmt1, or Dnmt3a, or both exclusively in forebrain excitatory neurons and found only double knockout (DKO) mice exhibited abnormal hippocampal CA1 long-term ...

The development of L-DOPA-induced dyskinesia (LID) is attributed to plastic responses triggered by dopamine (DA) receptor stimulation in the parkinsonian brain. This article reviews studies that have uncovered different levels of maladaptive plasticity in animal models of LID. Rats developing dyskinesia on chronic L-DOPA treatment show ...

Synaptic plasticity results in enduring changes in synaptic function. Localized protein synthesis is part of this process. Kosik and Krichevsky describe how a dynamic macromolecular structure, the RNA granule, may be a key element contributing to changes in protein production leading to synaptic ...

The purpose of this project was to understand rapidly induced and persistent forms of synaptic memory. The properties of the synaptic modifications underlying this plasticity could account for some of the adaptive and self organizing capabilities of simpl...

No study has yet investigated whether cortical plasticity in primary motor area (M1) is abnormal in patients with progressive supranuclear palsy (PSP). We studied M1 plasticity in 15 PSP patients and 15 age-matched healthy subjects. We used intermittent theta-burst stimulation (iTBS) to investigate long-term potentiation (LTP) and ...

... IN VIVO ANALYSIS, LEARNING, INDUCTION SYSTEMS, SPINAL COLUMN, DEGRADATION, ACTIVATION, SMELL, FUNCTIONS, SPATIAL ...

... MEMORY(PSYCHOLOGY), *SYNAPSE, *LEARNING ... BRAIN BARRIER, HIPPOCAMPUS, PHYSIOLOGICAL ... RATS, HUMANS, COMPUTERS. ...

... BIODETERIORATION, NERVE FIBERS, PROTEINS, DEGRADATION, MEMBRANES(BIOLOGY), ACTIVATION, SMELL, CALCIUM, FIBERS. ...

... Keywords: Synapse; Plasticity; Phosphorylation; Fatty acids; Lontophopersis. Descriptors : *SYNAPSE, *NERVE TRANSMISSION ...

... COMPUTER PROGRAMS, SIMULATORS, USER MANUALS, SIMULATION, ENVIRONMENTS, NETWORKS, INTERACTIONS, COMPUTERS, ...

DYT1 dystonia is a severe form of inherited dystonia, characterized by involuntary twisting movements and abnormal postures. It is linked to a deletion in the dyt1 gene, resulting in a mutated form of the protein torsinA. The penetrance for dystonia is incomplete, but both clinically affected and non-manifesting carriers of the DYT1 mutation exhibit impaired motor learning and ...

The neural cell adhesion molecule, NCAM, is a pivotal regulator of neural development, with key roles in axonal and dendritic growth and synaptic plasticity. Alterations in NCAM expression or proteolytic cleavage have been linked to human neuropsychiatric disorders such as schizophrenia, bipolar disorder and Alzheimer's disease, and may contribute to ...

Elevated expression of neuroinflammatory factors in the central nervous system (CNS) contributes to the cognitive impairment in CNS disorders such as injury, disease and neurodegenerative disorders. However, information on the role of specific neuroimmune factors in normal and abnormal CNS function is limited. In this study, we investigated the effects of chronic exposure to ...

The invention provides molecular systems for inducible and reversible inactivation of synaptic transmission. These systems can be used for studying neuronal networks and for treating conditions involving abnormally high neuronal activity or excitotoxic da...

Long-lasting plasticity of synaptic transmission is classically thought to be the cellular substrate for information storage in the brain. Recent data indicate however that it is not the whole story and persistent changes in the intrinsic neuronal excitability have been shown to occur in parallel to the induction of long-term synaptic ...

Abnormal processing of the amyloid precursor protein (APP) and beta-amyloid (Abeta) plaque accumulation are defining features of Alzheimer disease (AD), a genetically complex neurodegenerative disease that is characterized by progressive synapse loss and neuronal cell death. Abeta induces synaptic dysfunction in part by altering the endocytosis and ...

Executive functions of the brain are believed to require tonic dopamine inputs to the prefrontal cortex (PFC). It is unclear, however, how this background dopamine activity controls synaptic plasticity in the PFC, a possible underlying mechanism of executive functions. Using PFC slices, we show that pairing of dopamine with weak tetanic stimulation, a ...

Neurons recruit numerous mechanisms to facilitate the development of synaptic connections. However, little is known about activity-dependent mechanisms that control the timing and fidelity of this process. Here we describe a novel pathway used by neurons to regulate glutamate receptors at maturing central synapses. This pathway relies on communication between neurons and ...

Fragile X syndrome (FXS) is the leading inherited cause of mental retardation and autism spectrum disorders worldwide. It presents with a distinct behavioral phenotype which overlaps significantly with that of autism. Unlike autism and most common psychiatric disorders, the neurobiology of fragile X is relatively well understood. Lack of the fragile X mental retardation protein causes ...

... hypothesis postulates that long-term synaptic potentiation (LTP ... and optics (video-enhanced, differential interference ... that (1) the quanta] size density ...

... Accession Number : ADA181474. Title : Amine Neurotransmitter Regulation of Long-Term Synaptic Plasticity in Hippocampus. ...

... Accession Number : ADA170065. Title : Amine Neurotransmitter Regulation of Long-Term Synaptic Plasticity in Hippocampus. ...

Over the last 2 decades, a large number of neurophysiological and neuroimaging studies of patients with schizophrenia have furnished in vivo evidence for dysconnectivity, ie, abnormal functional integration of brain processes. While the evidence for dysconnectivity in schizophrenia is strong, its etiology, pathophysiological mechanisms, and significance for clinical symptoms ...

Levodopa-induced dyskinesia is a major complication of long-term dopamine replacement therapy for Parkinson's disease that becomes increasingly problematic in advanced Parkinson's disease. Although the cause of levodopa-induced dyskinesias is still unclear, recent work in animal models of the corticostriatal system has suggested that levodopa-induced dyskinesias might result from ...

Development of cognitive function requires the formation and refinement of synaptic networks of neurons in the brain. Morphological abnormalities of synaptic spines occur throughout the brain in a wide variety of syndromic and non-syndromic disorders of mental retardation (MR). In both neurons from human post-mortem tissue and mouse ...

The group I metabotropic glutamate receptor 5 (mGluR5) has been implicated in the development of cortical sensory maps. However its precise roles in the synaptic function and plasticity of thalamocortical connections remain unknown. Here we first show that in mGluR5 knockout mice bred onto a C57BL6 background cyto-architectonic differentiation into barrels ...

Exposure of newborn rats to antiepileptics such as barbiturates has long-lasting detrimental effects on the hippocampus and hippocampus-dependent behavior. However, the long-term consequences of neonatal administration with barbiturates on the hippocampal synaptic plasticity remain unresolved. In this study, we investigated the long-lasting effects of a ...

Structural abnormalities are demonstrated in various neuropsychiatric disorders, including Alzheimer's disease, Parkinson's disease, and even major depression. On the other hand, recent studies have demonstrated the structural and functional modifications in the adult brain that are associated with synaptic plasticity and neurogenesis. ...

Rac1, a protein of the Rho GTPase subfamily, has been implicated in neuronal and spine development as well as the formation of synapses with appropriate partners. Dendrite and spine abnormalities have been implicated in several psychiatric disorders such as Fragile X syndrome, where neurons show a high density of long, thin, and immature dendritic spines. Although ...

Functional rehabilitation of the cortex following peripheral or central nervous system damage is likely to be improved by a combination of behavioural training and natural or therapeutically enhanced synaptic plasticity mechanisms. Experience-dependent plasticity studies in the somatosensory cortex have begun to reveal those ...

Neuronal and nonneuronal plasticity are both affected by environmental and experiential factors. Remodeling of existing neurons induced by such factors has been observed throughout the brain, and includes alterations in dendritic field dimensions, synaptogenesis, and synaptic morphology. The brain loci affected by these plastic ...

Fragile X syndrome (FXS) is the most common inherited form of intellectual disability and the leading genetic cause of autism. It is associated with the lack of fragile X mental retardation protein (FMRP), a regulator of protein synthesis in axons and dendrites. Studies on FXS have extensively focused on the postsynaptic changes underlying dysfunctions in long-term plasticity. ...

In many regions of the brain, including the mammalian cortex, the strength of synaptic transmission can be bidirectionally regulated by cortical activity (synaptic plasticity). One line of evidence indicates that long-term synaptic potentiation (LTP) and long-term synaptic depression (LTD), ...

Experience-dependent development of visual cortex depends on the balance between excitatory and inhibitory activity. This activity is regulated by key excitatory (NMDA, AMPA) and inhibitory (GABA_A) receptors. The composition of these receptors changes developmentally, affecting the excitatory�inhibitory (E/I) balance and synaptic ...

There is growing evidence that NMDA receptor-dependent long-term potentiation (LTP) in the hippocampus mediates the synaptic plasticity that underlies spatial learning and memory. LTP deficiencies correlate well with spatial memory deficits and LTP enhancements may improve spatial memory. In addition, LTP deficiencies are associated with ...

The process of axonal and dendritic development establishes the synaptic circuitry of the central nervous system (CNS) and is the result of interactions between intrinsic molecular factors and the external environment. One growth factor that has a compelling function in neuronal development is the neurotrophin brain-derived neurotrophic factor (BDNF). BDNF participates in ...

Page 1. AD-A260 322 'n DOata FEntered) Theory of Synaptic Plasticity in Visual Cortex Technical Report #16. 2.HO ~ m GOV AC ESONN . ...

Functional and structural changes in synapses, specific regions for communication between nerve cells, are thought to be the basis for storing information, and modulating neuronal behavior. This continuous remodeling is defined as synaptic plasticity. The...

The present invention provides compositions and methods for enhancing cognitive function and synaptic plasticity. According to the method, Ca.sup.++ influx into excitatory neurons (nerve cells) is decreased by treatment with a number of different agents i...

The interactions between certain ?-synuclein (SNCA) conformations and dopamine (DA) metabolism cause selective DA neuron degeneration in Parkinson's disease (PD). Preclinical research on PD took advantage of increasing studies involving different animal models which express different forms of mutated SNCA. Transgenic animals expressing mutant ?-synucleins such as mice transgenic for A53T-SNCA (TG) ...

Epidemiological studies estimate that greater than 60% of the adult US population may be categorized as either overweight or obese, and there is a growing appreciation that the complications of obesity extend to the central nervous system (CNS). While the vast majority of these studies have focused on the hypothalamus, more recent studies suggest that the complications of obesity may also affect ...

... eyes by sec- tioning an extraocular muscle results in a loss of binocular responsiveness. Subsequent experiments have ...

of Synaptic PlasticityExpression of Synaptic Plasticity Harel Shouval1, Jeff Gavornik1, Marshall Shuler2, Mark. if light is flashed to right eye it gets a reward after 2x licks. Shuler and Bear, 2006 Marshall G. Shuler training 0f those 50% show transient increase 22% transient inhibition 28% peak at reward � � ...

, and J. Hillston. Modelling the influence of RKIP on the ERK signalling pathway using the stochastic