Various forms of synaptic plasticity, including spike timing-dependent plasticity, can be accounted for by calcium-dependent models of synaptic plasticity. However, recent results in which synaptic plasticity is induced by multi-spike protocols cannot simply be accounted for by linear superposition of plasticity due to spike pairs or by existing calcium-dependent models. In this paper, we show ...

Direction selectivity in simple cells of primary visual cortex, defined from their spike responses, cannot be predicted using linear models. It has been suggested that the shunting inhibition evoked by visual stimulation is responsible for the nonlinear component of direction selectivity. Cortical inhibition would suppress a neuron's firing when stimuli move in the nonpreferred direction, but w...

62 Intracortical recordings comprise both fast events, action potentials (APs), and slower 63 events, known as local field potentials (LFPs). While it is believed that LFPs mostly 64 reflect local synaptic activity, it is unclear which of their signal components are most 65 closely related to synaptic potentials, and would therefore be causally related to the 66 occurrence of individual APs. Th...

abstract in order to study the inheritance of grain yield and its components in bread wheat, two cultivars, karchyya(drought and salinity tolerant) and gaspard (sensitive to drought and salinity stress) were crossed.parents together with f1, f2, f3, bc1and bc2 generations were evaluated using a randomized complete block design with three replications in 2008-2009 growing season.grain weight per...

Intracortical recordings comprise both fast events, action potentials (APs), and slower events, known as local field potentials (LFPs). Although it is believed that LFPs mostly reflect local synaptic activity, it is unclear which of their signal components are most closely related to synaptic potentials and would therefore be causally related to the occurrence of individual APs. This issue is c...

In spike-timing-dependent plasticity (STDP), the order and precise temporal interval between presynaptic and postsynaptic spikes determine the sign and magnitude of long-term potentiation (LTP) or depression (LTD). STDP is widely utilized in models of circuit-level plasticity, development, and learning. However, spike timing is just one of several factors (including firing rate, synaptic cooper...

Abstract We present a collection of modeling tools for the analysis of neuronal spike trains as point processes. The conditional intensity can be modeled to depend on variables such as time elapsed since the last spike, time elapsed since the onset of stimulus, etc., and the models can be estimated nonparametrically by penalized likelihood Poisson regression or logistic regression. Model diagno...

We study the sum of many independent spike trains and ask whether the resulting spike train has Poisson statistics or not. It is shown that for a non-Poissonian statistics of the single spike train, the resulting sum of spikes has exponential interspike interval (ISI) distributions, vanishing the ISI correlation at a finite lag but exhibits exactly the same power spectrum as the original spike ...

ON-OFF transient ganglion cells of the turtle retina show distinct spike-event patterns in response to abrupt intensity changes, such as during saccadic eye movements. These patterns consist of two main spike events, with the latency of each event showing a systematic dependency on stimulus contrast. Whereas the latency of the first event decreases monotonically with increasing contrast, as exp...

Spiking neurons are very flexible computational modules, which can implement with different values of their adjustable synaptic parameters an enormous variety of different transformations F from input spike trains to output spike trains. We examine in this letter the question to what extent a spiking neuron with biologically realistic models for dynamic synapses can be taught via spike-timing-d...