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Artikel Jurnal
Questions About STDP as a General Model of Synaptic Plasticity
According to spike-timing-dependent plasticity (STDP), the timing of the Na+ spike relative to the EPSP determines whether LTP or LTD will occur. Here, we review our reservations about STDP. Most investigations of this process have been done under conditions in which the spike is evoked by…
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Artikel Jurnal
Novel roles for immune molecules in neural development: Implications for neurodevelopmental disoders
Although the brain has classically been considered "immune-privileged," current research suggests extensive communication between the nervous and the immune systems in both health and disease. Recent studies demonstrate that immune molecules are present at the right place and time to modulate the…
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Artikel Jurnal
GABAergic synaptic transmission regulates calcium influx during spike-timing dependent plasticity
Coincident pre- and postsynaptic activity of hippocampal neurons alters the strength of gamma-aminobutyric acid (GABAA)-mediated inhibition through a Ca2+-dependent regulation of cation-chloride cotransporters. This long-term synaptic modulation is termed GABAergic spike-timing dependent plasticity…
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Artikel Jurnal
NMDAR-mediated calcium transients elicited by glutamate co-release at developing inhibitory synapses
Before hearing onset, the topographic organization of the inhibitory sound localization pathway from the medial nucleus of the trapezoid body (MNTB) to the lateral superior olive (LSO) is refined by means of synaptic silencing and strengthening. During this refinement period MNTB-LSO synapses not…
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Artikel Jurnal
Spike-timing dependent plasticity beyond synapse - pre- and post-synaptic plasticity of intrinsic neuronal excitability
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. Persistent changes in the intrinsic neuronal excitability have been shown to occur in parallel to…
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Artikel Jurnal
Vesicular release of glutamate utilizes the proton gradient between the vesicle and synaptic cleft
Glutamate is released from synaptic vesicles following formation of a fusion pore, connecting the vesicle interior with the synaptic cleft. Release is proposed to result from either full fusion of the vesicle with the terminal membrane or by ‘kiss-and-run’, where release occurs through the fusion…
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Artikel Jurnal
A developmental sensitive period for spike timing-dependent plasticity in the retinotectal projection
The retinotectal projection in Xenopus laevis has been shown to exhibit correlation-based refinement of both anatomical and functional connectivity during development. Spike timing-dependent plasticity (STDP) is an appealing experimental model for correlation-based synaptic plasticity because, in…
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Artikel Jurnal
Timing is not everything: neuromodulation opens the STDP gate
Spike timing dependent plasticity (STDP) is a temporally specific extension of Hebbian associative plasticity that has tied together the timing of presynaptic inputs relative to the postsynaptic single spike. However, it is difficult to translate this mechanism to in vivo conditions where there is…
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Artikel Jurnal
Spike timing dependent plasticity in the intact brain: counteracting spurious spike coincidences.
A computationally rich algorithm of synaptic plasticity has been proposed based on the experimental observation that the sign and amplitude of the change in synaptic weight is dictated by the temporal order and temporal contiguity between pre- and post-synaptic activities. For more than a decade…
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Artikel Jurnal
A Ca2+-based computational model for NDMA receptor-dependent synaptic plasticity at individual post-synaptic spines in the hippocampus
Associative synaptic plasticity is synapse specific and requires coincident activity in presynaptic and postsynaptic neurons to activate NMDA receptors (NMDARs). The resultant Ca2+ influx is the critical trigger for the induction of synaptic plasticity. Given its centrality for the induction of…
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Artikel Jurnal
Genetic controls balancing excitatory and inhibitory synaptogenesis in neurodevelopmental disorder models
Proper brain function requires stringent balance of excitatory and inhibitory synapse formation during neural circuit assembly. Mutation of genes that normally sculpt and maintain this balance results in severe dysfunction, causing neurodevelopmental disorders including autism, epilepsy and Rett…
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Artikel Jurnal
Rate and pulse based plasticity governed by local synaptic state variables
Classically, action-potential-based learning paradigms such as the Bienenstock-Cooper-Munroe (BCM) rule for pulse rates or spike timing dependent plasticity (STDP) for pulse pairings have been experimentally demonstrated to evoke long-lasting synaptic weight changes (i.e. plasticity). However…
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Artikel Jurnal
Experience-Dependent Changes in Excitatory & Inhibitory Receptor Subunit Expression in Visual Cortex
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 (GABAA) receptors. The composition of these receptors changes developmentally, affecting the…
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Artikel Jurnal
The mossy fiber bouton: the common or the unique synapse?
Synapses are the key elements for signal processing and plasticity in the brain. They are composed of nearly the same structural subelements, an apposition zone including a pre- and postsynaptic density, a cleft and a pool of vesicles. It is, however, their actual composition that determines their…
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Artikel Jurnal
The activity requirements for spike timing-dependent plasticity in the hippocampus
Synaptic plasticity has historically been investigated most intensely in the hippocampus and therefore it is somewhat surprising that the majority of studies on spike timing-dependent plasticity (STDP) have focused not in the hippocampus but on synapses in the cortex. One of the major reasons for…
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Artikel Jurnal
Differential regulation of synaptic vesicle tethering and docking by UNC-18 and TOM-1
The assembly of SNARE complexes between syntaxin, SNAP-25 and synaptobrevin is required to prime synaptic vesicles for fusion. Since Munc18 and tomosyn compete for syntaxin interactions, the interplay between these proteins is predicted to be important in regulating synaptic transmission. We…