![]() In fact, dendrites locking in synchrony can lead to sustained firing of the cell. As a consequence of global locking, even individual synaptic inputs can affect the timing of action potentials. We show how the biophysical properties of the dendrites determine the global locking and how it can be controlled by synaptic inputs. Our mathematical theory shows that indeed even when the dendritic oscillators are weakly coupled, they lock their phases and give global oscillations. Here we analyze whether local dendritic oscillators can produce cell-wide voltage oscillations. This can turn the dendritic tree into a network of sparsely spaced local oscillators. The distribution of the active membrane channels throughout the cell is often highly non-uniform. ![]() A prominent phenomenon resulting from such ion channels are voltage oscillations. The dendritic tree of a neuron, which receives most of the inputs, expresses ion channels that can generate nonlinear dynamics. This is especially relevant for neurons since these spatially extended cells process local synaptic inputs to generate global action potential output. Our results suggest that dendritic oscillations enable the dendritic tree to operate on more global temporal and spatial scales than previously thought notably that local dendritic activity may be a mechanism for generating on-going whole-cell voltage oscillations.Ī central issue in biology is how local processes yield global consequences. In turn, dendritic coherence is able to gate the integration and propagation of synaptic signals to the soma, ultimately leading to an effective control of somatic spike generation. As a direct consequence, we show how input to the dendrites can modulate phase-locking behavior and hence global dendritic coherence. We characterize how the phase-locking properties depend on key parameters of the oscillating dendrite: the electrotonic properties of the (active) dendritic segment, and the intrinsic properties of the dendritic oscillators. Combining weakly coupled oscillator methods with cable theoretic arguments, we derive phase-locking states for multiple oscillating dendritic compartments. Here, we develop a mathematical framework to analyze the interactions of local dendritic oscillations and the way these interactions influence single cell computations. However, recent evidence about the presence of oscillations in dendrites suggests a qualitatively different mode of operation: the instantaneous phase of such oscillations can depend on a long history of inputs, and under appropriate conditions, even dendritic oscillators that are remote may interact through synchronization. Under this localist account, neurons compute near-instantaneous mappings from their current input to their current output, brought about by somatic summation of dendritic contributions that are generated in functionally segregated compartments. Traditionally, these computations have been characterized as both temporally and spatially localized. The dendritic tree contributes significantly to the elementary computations a neuron performs while converting its synaptic inputs into action potential output.
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