In some types of neurons, the distributed synapses onto a neuron are location-independent in the sense that, regardless of a synapse's distance from the soma, each synapse has an equal efficacy for inducing postsynaptic action potentials. This occurs because the postsynaptic conductance at more distal synapses is scaled up, counteracting the electrotonic attenuation. It is unknown, however, how such a configuration is generated and maintained. The answer may lie in a particular form of spike-timing dependent plasticity (STDP) called anti-STDP. This idea will be tested in biologically realistic neuron models. In particular, both an active equivalent cable model and a NEURON simulation using realistic neuron morphologies will be used to explore this idea. Additionally, these models will be used to explore the interaction between conventional STDP and anti-STDP. At issue is the general question of how learning mechanisms and homeostatic mechanisms coexist within neurons to provide a balance of both synaptic input selectivity and synaptic input equalization.
| Rumsey, Clifton C; Abbott, L F (2006) Synaptic democracy in active dendrites. J Neurophysiol 96:2307-18 |
| Rumsey, Clifton C; Abbott, L F (2004) Equalization of synaptic efficacy by activity- and timing-dependent synaptic plasticity. J Neurophysiol 91:2273-80 |
