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Updated: Aug 15, 2026

Preparation of Aplysia Sensory-motor Neuronal Cell Cultures
Published on: June 8, 2009
Long-term synaptic changes produced by a cellular analog of classical conditioning in Aplysia
1Department of Neurobiology and Anatomy, University of Texas Medical School, Houston 77225.
Abstract:
A change in synaptic strength arising from the activation of two neuronal pathways at approximately the same time is a form of associative plasticity and may underlie classical or Pavlovian conditioning. A cellular analog of a classical conditioning protocol produces short-term associative plasticity at the connections between sensory and motor neurons in Aplysia. A similar training protocol produced long-term (24-hour) enhancement of excitatory postsynaptic potentials (EPSPs). EPSPs produced by sensory neurons in which activity was paired with a reinforcing stimulus were significantly larger than unpaired controls 24 hours after training. Thus, associative plasticity at the sensory to motor neuron connection can occur in a long-term form in addition to the short-term form. In this system, it should be possible to analyze the molecular mechanisms underlying long-term associative plasticity and classical conditioning.
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