We developed a CA1
pyramidal cell model calibrated with a broad spectrum of in vitro data. Using simultaneous
dendritic and somatic recordings, and combining results for two different response measures
(peak vs. mean EPSP), two different stimulus formats (single shock vs. 50 Hz trains),
and two different spatial integration conditions (within vs. between-branch summation),
we found the cell's subthreshold responses to paired inputs are best described as a sum of
nonlinear subunit responses, where the subunits correspond to different dendritic branches.
In addition to suggesting a new type of experiment and providing testable predictions, our
model shows how conclusions regarding synaptic arithmetic can be influenced by an array
of seemingly innocuous experimental design choices.
References:
1 .
Poirazi P, Brannon T, Mel BW (2003) Arithmetic of subthreshold synaptic summation in a model CA1 pyramidal cell. Neuron 37:977-87 [PubMed]
2 .
Poirazi P, Brannon T, Mel BW (2003) Pyramidal neuron as two-layer neural network. Neuron 37:989-99 [PubMed]
3 .
Poirazi P, Brannon T, Mel BW (2003ab-sup) Online Supplement: About the Model Neuron 37 Online:1-20
4 .
Polsky A, Mel BW, Schiller J (2004) Computational subunits in thin dendrites of pyramidal cells. Nat Neurosci 7:621-7 [PubMed]
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