Information Processing in Dendrites and Spines

Neuronal dendrites and dendritic spines influence the integration of the synaptic input in a variety of ways. At the most basic level, their structure and passive membrane properties determine how synaptic inputs are integrated. In addition, dendrites and spines contain a variety of voltage-gated channels, often expressed non-uniformly in the dendritic tree. In many neurons these channels have been shown to support the backpropagation of axonally initiated action potentials. Local dendritic spikes can also be initiated by synaptic input, through regenerative activation of voltage-gated sodium and calcium channels or NMDA receptors. These dendritic spikes can influence action potential output and trigger synaptic plasticity. The ability of dendritic spines to compartmentalize chemical and electrical signals also plays a role in synaptic integration and plasticity. Collectively, these properties allow neurons to perform a range of computations that are likely to be vital for the proper functioning of neural circuits and behavior.