Functional topography of connections linking mirror-symmetric maps in the mouse olfactory bulb

Neuron. 2003 Apr 24;38(2):265-76. doi: 10.1016/s0896-6273(03)00194-6.


In rodents, each main olfactory bulb contains two mirror-symmetric glomerular maps, a feature not found in the initial topographic maps of other sensory systems. Targeting tracer injections to identified glomeruli revealed that isofunctional odor columns-translaminar assemblies connected to a given glomerulus-were specifically and reciprocally interconnected through a mutually inhibitory circuit with exquisite topographic specificity. Thus, instead of containing two mirror-symmetric maps, we propose that the olfactory bulb contains a single integrated map in which isofunctional odor columns are connected through an intrabulbar link, analogous to the specific horizontal connections linking iso-orientation columns in primary visual cortex.

MeSH terms

  • Animals
  • Brain Mapping / methods*
  • Green Fluorescent Proteins
  • Luminescent Proteins / biosynthesis
  • Luminescent Proteins / genetics
  • Mice
  • Mice, Mutant Strains
  • Neural Inhibition / physiology
  • Olfactory Bulb / anatomy & histology*
  • Olfactory Bulb / cytology
  • Olfactory Bulb / physiology
  • Olfactory Pathways / anatomy & histology*
  • Olfactory Pathways / cytology
  • Olfactory Pathways / physiology
  • Olfactory Receptor Neurons / cytology
  • Olfactory Receptor Neurons / physiology
  • Receptors, Odorant / biosynthesis
  • Receptors, Odorant / genetics


  • Luminescent Proteins
  • Receptors, Odorant
  • Green Fluorescent Proteins