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Classical and operant conditioning differentially modify the intrinsic properties of an identified neuron


A long-standing debate in neuroscience is whether classical and operant conditioning are mechanistically similar or distinct. The feeding behavior of Aplysia provides a model system suitable for addressing this question. Here we report that classical and operant conditioning of feeding behavior differentially modify the intrinsic excitability of neuron B51, a critical element for the expression of the feeding response, thus revealing that these two forms of associative learning differ at the cellular level.

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Figure 1: In vivo and in vitro classical conditioning of feeding behavior.
Figure 2: Cellular correlates of classical conditioning.


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We thank H.N. Nguyen for training many of the animals included in this study. This work was supported by the US National Institute of Mental Health (grant MH 58321).

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Correspondence to John H Byrne.

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The authors declare no competing financial interests.

Supplementary information

Supplementary Fig. 1

Classical conditioning training protocols. (PDF 196 kb)

Supplementary Fig. 2

Classical conditioning did not alter the CS-evoked inhibitory synaptic input to neuron B51. (PDF 192 kb)

Supplementary Fig. 3

Classical conditioning did not alter either the resting membrane potential or the input resistance of neuron B51. (PDF 291 kb)

Supplementary Discussion (PDF 139 kb)

Supplementary Methods (PDF 164 kb)

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Lorenzetti, F., Mozzachiodi, R., Baxter, D. et al. Classical and operant conditioning differentially modify the intrinsic properties of an identified neuron. Nat Neurosci 9, 17–19 (2006).

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