In the olfactory bulb, the processing units for odor discrimination are believed
to involve dendrodendritic synaptic interactions between mitral and granule cells.
There is increasing anatomical evidence that these cells are organized in columns,
and that the columns processing a given odor are arranged in widely distributed arrays.
Experimental evidence is lacking on the underlying learning mechanisms for how these
columns and arrays are formed.
We have used a simplified realistic circuit model to test the hypothesis that
distributed connectivity can self-organize through an activity-dependent dendrodendritic
The results point to action potentials propagating in the mitral cell lateral dendrites
as playing a critical role in this mechanism, and suggest a novel and robust learning
mechanism for the development of distributed processing units in a cortical structure.
Migliore M, Inzirillo C, Shepherd GM (2007) Learning mechanism for column formation in the olfactory bulb. Front Integr Neurosci 1:12 [PubMed]