Dendritic Excitation Dependence on Synaptic Democracy in CA1 Pyramidal Neurons
نویسندگان
چکیده
12 Synaptic democracy is believed to be an important effect that enables distal 13 synapses to contribute information to the soma. Synaptic democracy is found in 14 hippocampal CA1 pyramidal neurons, which is an important area of the brain 15 for learning and memory. Previous computational work by Sterratt et al [1] 16 show that synaptic democracy arises in a model of a CA1 pyramidal neuron 17 when sufficient synapses are synchronously activated given that the calcium 18 concentration is homeostatically maintained. However, in this work only a 5Hz 19 excitatory postsynaptic potential (EPSP) was tested. We explored how different 20 input vectors might affect the dynamics of synaptic democracy and the neuron 21 as a whole. We found that high frequency stimulation compensated for a sub22 threshold number of synapses allowing for synaptic democracy. Interestingly, in 23 the cases with supra-threshold synapse numbers, higher frequency synaptic 24 inputs abolished synaptic democracy. 25
منابع مشابه
Synaptic democracy in active dendrites.
Given the extensive attenuation that can occur along dendritic cables, location within the dendritic tree might appear to be a dominant factor in determining the impact of a synapse on the postsynaptic response. By this reasoning, distal synapses should have a smaller effect than proximal ones. However, experimental evidence from several types of neurons, such as CA1 pyramidal cells, indicates ...
متن کاملHippocampal Feedforward Inhibition Focuses Excitatory Synaptic Signals into Distinct Dendritic Compartments
Feedforward inhibition controls the time window for synaptic integration and ensures temporal precision in cortical circuits. There is little information whether feedforward inhibition affects neurons uniformly, or whether it contributes to computational refinement within the dendritic tree. Here we demonstrate that feedforward inhibition crucially shapes the integration of synaptic signals in ...
متن کاملDPP6 Establishes the A-Type K+ Current Gradient Critical for the Regulation of Dendritic Excitability in CA1 Hippocampal Neurons
Subthreshold-activating A-type K(+) currents are essential for the proper functioning of the brain, where they act to delay excitation and regulate firing frequency. In CA1 hippocampal pyramidal neuron dendrites, the density of A-type K(+) current increases with distance from the soma, playing an important role in synaptic integration and plasticity. The mechanism underlying this gradient has, ...
متن کاملDendritic mechanisms of phase precession in hippocampal CA1 pyramidal neurons.
Dual whole-cell patch clamp recordings from the soma and dendrites of CA1 pyramidal neurons located in hippocampal slices of adult rats were used to examine the potential mechanisms of phase precession. To mimic phasic synaptic input, 5-Hz sine wave current injections were simultaneously delivered both to the soma and apical dendrites (dendritic current was 180 degrees out-of-phase with soma). ...
متن کاملBilinearity in Spatiotemporal Integration of Synaptic Inputs
Neurons process information via integration of synaptic inputs from dendrites. Many experimental results demonstrate dendritic integration could be highly nonlinear, yet few theoretical analyses have been performed to obtain a precise quantitative characterization analytically. Based on asymptotic analysis of a two-compartment passive cable model, given a pair of time-dependent synaptic conduct...
متن کامل