>>12178211I depends on the type of memory. For object recognition it is most likely related to pyramidal neurons (the most important neuron type in the neocortex). For pyramidal neurons, its basal dendrites will fire an NMDA spike when sufficient synapses on a given dendrite fire if they are in close proximity and within a close enough time interval. The NMDA spike partially depolarises the soma for a relatively long period of time but does not generate axonal spike. The axonal spike can be caused by a later proximal synapse. The basal synapses act as a kind of prediction mechanism for the proximal synapse.
When multiple neurons are triggered at the same time by that mechanism spiny stellate cells (which connect to multiple pyramidal cells) shut show all but the first neuron. Cells which have been partially depolarised will fire before those which have not and spiny stellate cells are extremely fast. The firing of the first propagates along the axon to the next cell, but also backwards towards the dendrites which caused the firing allowing the synapses to be reinforced for making a correct prediction - a sparse pattern prediction mechanism.
Apical dendrites on pyramidal neurons play a roll in feedback from higher cortical areas and use bursting rather than single spiking. It's worth pointing out that there is more feedback than feedforward in the brain.
Episodic memory is the domain of the human hippocampus. In there there is an sort of associative memory and once again it's full of pyramidal neurons (along with others). The associative memory allows the whole episode top be recalled from only a fragment of it. In addition there are place cells and grid cells which enable you to form a mental map of places.
