Enhanced Release Probability without Changes in Synaptic Delay during Analogue–Digital Facilitation

Cells, Год журнала: 2024, Номер 13(7), С. 573 - 573

Опубликована: Март 26, 2024

Neuronal timing with millisecond precision is critical for many brain functions such as sensory perception, learning and memory formation. At the level of chemical synapse, synaptic delay determined by presynaptic release probability (Pr) waveform action potential (AP). For instance, paired-pulse facilitation or long-term potentiation are associated reductions in delay, whereas depression an increased delay. Parallelly, AP broadening that results from inactivation voltage gated potassium (Kv) channels responsible repolarization phase delays response, sodium (Nav) reduces latency. However, whether modulated during depolarization-induced analogue–digital (d-ADF), a form context-dependent induced prolonged depolarization neuron mediated voltage-inactivation Kv1 channels, remains unclear. We show here despite Pr being elevated d-ADF at pyramidal L5-L5 cell synapses, surprisingly unchanged. This finding suggests both Pr- AP-dependent changes compensate each other d-ADF. conclude that, contrast to short- modulations release, not affected because opposite interaction

Язык: Английский

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Synaptopodin is required for long-term depression at Schaffer collateral-CA1 synapses

Molecular Brain, Год журнала: 2024, Номер 17(1)

Опубликована: Апрель 2, 2024

Synaptopodin (SP), an actin-associated protein found in telencephalic neurons, affects activity-dependant synaptic plasticity and dynamic changes of dendritic spines. While being required for long-term depression (LTD) mediated by metabotropic glutamate receptor (mGluR-LTD), little is known about its role other forms LTD induced low frequency stimulation (LFS-LTD) or spike-timing dependent (STDP). Using electrophysiology ex vivo hippocampal slices from SP-deficient mice (SPKO), we show that absence SP associated with a deficit at Sc-CA1 synapses LFS-LTD STDP. As to require AMPA- receptors internalization IP3-receptors calcium signaling, tested western blotting immunochemistry if there were their expression which be reduced. not able induce LTD, potentiation (LTP), albeit diminished SPKO, can recovered using stronger protocol. In SPKO no differences NMDAR, are the primary site signalling LTP. Our study shows, first time, key requirement allow induction synapses.

Язык: Английский

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Understanding Cerebellar Input Stage through Computational and Plasticity Rules

Опубликована: Май 7, 2024

A central hypothesis on brain functioning is that plasticity regulates the signals transfer function by modifying efficacy of synaptic transmission. In cerebellum, granular layer has been shown to control gain transmitted through mossy fiber pathway. Until now, impact incoming activity patterns was analyzed combining electrophysiological recordings in acute cerebellar slices and computational modeling, unraveling a broad spectrum different forms layer, often along with intrinsic excitability changes. Here, we attempt provide brief overview most prominent at excitatory synapses formed fibers onto principal neurons (granule cells, Golgi cells unipolar brush cells) layer. Specifically, will highlight current understanding mechanisms their functional implications plasticity, providing valuable insights into how inputs are processed reconfigured input stage.

Язык: Английский

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Neural oscillations and memory: unraveling the mechanisms of anesthesia-induced amnesia

Frontiers in Neuroscience, Год журнала: 2024, Номер 18

Опубликована: Ноя. 14, 2024

General anesthesia is a widely used medical practice, affecting more than 300 million patients annually. Despite its ubiquity, the underlying mechanisms through which anesthetic agents induce amnesia remain poorly understood. This review explores impact of general anesthetics on memory function, with particular focus role neural oscillations in anesthesia-induced suppression. Neural oscillations, such as theta, gamma, delta slow (SO), spindles, and sharp wave ripples (SWR), are critical for formation consolidation. Various modulate these ways that affect memory, even at subanesthetic concentrations. We highlight recent findings molecular electrophysiological by influence memory-related including inhibition synaptic plasticity, alterations spike-timing-dependent plasticity (STDP), disruption cross-frequency couplings like theta-gamma SO-spindle-SWR. Additionally, addresses significance age anesthesia-related loss, elderly being particularly vulnerable to long-term cognitive decline. Electrophysiological techniques, Electroencephalography (EEG); advanced neuromodulation chemogenetics, optogenetics, have provided insights into dynamics underpinning amnesia, yet causal relationship between EEG rhythms impairment remains be fully elucidated. underscores importance further research interaction anesthesia, memory. Understanding will not only advance theoretical knowledge but also aid development safer strategies mitigate postoperative dysfunction, especially high-risk populations.

Язык: Английский

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Input signal accumulation capability of the FitzHugh–Nagumo neuron

Chaos An Interdisciplinary Journal of Nonlinear Science, Год журнала: 2024, Номер 34(12)

Опубликована: Дек. 1, 2024

We present numerical results on the effects of two presynaptic FitzHugh–Nagumo neurons a postsynaptic neuron under unidirectional electrical coupling. The affect not simultaneously but with certain time shift. consider cases where amplitudes spikes can be both higher and lower than excitation threshold level. latter case receives main attention in our work. carefully examine conditions which is excited by asynchronous external spikes. With arbitrarily chosen parameters, almost incapable accumulating energy signals, unlike, for example, leaky integrate-and-fire neuron. In this case, only excites very short delay between impulses. However, we have discovered, first time, parameter region possible even significant delays impulses subthreshold amplitudes. explain effect detail describe mechanism behind its occurrence. identify boundaries plane coupling coefficient varying control values neurons. has previously been used as node spiking neural networks training via spike-timing-dependent plasticity due to lack an effect. detection range parameters makes potential application STDP possible.

Язык: Английский

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