Decoding Temporal Information Through Slow Lateral Excitation in the Olfactory System of Insects
Sensory information is represented in a spatio-temporal code in the antennal lobe, the first processing stage of the olfactory system of insects. We propose a novel mechanism for decoding this information in the next processing stage, the mushroom body. The Kenyon cells in the mushroom body of insects exhibit lateral excitatory connections at their axons. We demonstrate that slow lateral excitation between Kenyon cells allows one to decode sequences of activity in the antennal lobe. We are thus able to clarify the role of the existing connections as well as to demonstrate a novel mechanism for decoding temporal information in neuronal systems. This mechanism complements the variety of existing temporal decoding schemes. It seems that neuronal systems not only have a rich variety of code types but also quite a diversity of algorithms for transforming different codes into each other.
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- Destexhe A, Mainen ZF, Sejnowski TJ (1998) Kinetic models of synaptic transmission. In: C Koch, I Segev, eds. Methods in Neuronal Modeling, 2nd ed., MIT Press, Cambridge, MA. pp. 1-26.Google Scholar
- Jeffres LA (1948) A place theory of sound localization. J. Comp. Physiol. Psychol. 41: 35-39.Google Scholar
- Laurent G, MacLeod K, Wehr M (1998) Spatiotemporal structure of olfactory inputs to the mushroom bodies. Learn. & Mem. 5: 124-132.Google Scholar
- Rall W (1967) Distinguishing theoretical synaptic potentials computed for different soma-dendritic distributions of synaptic inputs. J. Neurophys. 30: 1138-1168.Google Scholar
- Rall W (1989) Cable theory for dendritic neurons. In: C Koch, I Segev, eds. Methods in Neuronal Modeling: From Synapses to Networks, MIT Press, Cambridge. pp. 9-62.Google Scholar
- Stopfer M, Jayaraman V, Laurent G (2003) Spatiotemporal code for odor identity and concentration. In preparation.Google Scholar
- Teyke T, Gelperin A (1999) Olfactory oscillations augment odor discrimination not odor identification by Limax CNS. Neuro Report 10: 1061-1068.Google Scholar