Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

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.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

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


  1. Pavlov, I.P. Conditioned Reflexes (Oxford Univ. Press, Oxford, 1927).

    Google Scholar 

  2. Skinner, B.F. The Behavior of Organisms: An Experimental Analysis (Appleton-Century-Crofts, New York, 1938).

    Google Scholar 

  3. Rescorla, R.A. & Solomon, R.L. Psychol. Rev. 74, 151–182 (1967).

    Article  CAS  Google Scholar 

  4. Gormezano, I. & Tait, R.W. Pavlov. J. Biol. Sci. 11, 37–55 (1976).

    CAS  PubMed  Google Scholar 

  5. Raymond, J.L., Baxter, D.A., Buonomano, D.V. & Byrne, J.H. Neural Netw. 5, 789–803 (1992).

    Article  Google Scholar 

  6. Lechner, H.A., Baxter, D.A. & Byrne, J.H. J. Neurosci. 20, 3369–3376 (2000).

    Article  CAS  Google Scholar 

  7. Brembs, B., Lorenzetti, F.D., Reyes, F.D., Baxter, D.A. & Byrne, J.H. Science 296, 1706–1709 (2002).

    Article  CAS  Google Scholar 

  8. Nargeot, R., Baxter, D.A. & Byrne, J.H. J. Neurosci. 19, 2247–2260 (1999).

    Article  CAS  Google Scholar 

  9. Nargeot, R., Baxter, D.A. & Byrne, J.H. J. Neurosci. 19, 2261–2272 (1999).

    Article  CAS  Google Scholar 

  10. Mozzachiodi, R., Lechner, H.A., Baxter, D.A. & Byrne, J.H. Learn. Mem. 10, 478–494 (2003).

    Article  Google Scholar 

  11. Plummer, M.R. & Kirk, M.D. J. Neurophysiol. 63, 539–558 (1990).

    Article  CAS  Google Scholar 

  12. Morton, D.W. & Chiel, H.J. J. Comp. Physiol. [A] 172, 17–32 (1993).

    Article  CAS  Google Scholar 

  13. Byrne, J.H. Physiol. Rev. 67, 329–439 (1987).

    Article  CAS  Google Scholar 

  14. Zhang, W. & Linden, D.J. Nat. Rev. Neurosci. 4, 885–900 (2003).

    Article  CAS  Google Scholar 

  15. Schultz, W. Neuron 36, 241–263 (2002).

    Article  CAS  Google Scholar 

Download references


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).

Author information

Authors and Affiliations


Corresponding author

Correspondence to John H Byrne.

Ethics declarations

Competing interests

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)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

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).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

This article is cited by


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing