Propagation of calcium waves in the Hermissenda type B photoreceptor

Hermissenda crassicornis is a seaslug that can be classically conditioned t o associate light (the conditioned stimulus) with turbulence (the unconditi oned stimulus). Of particular importance is discovering what aspect of the light and turbulence interaction within the type B photoreceptor mediates m emory storage. The purpose of this study is to test the hypothesis that cal cium released by phototransduction combines non-linearly with calcium resul ting from GABA stimulation by evaluating whether GABA can produce a calcium wave that reaches the soma. Simulations show that GABA stimulation causes an increase in calcium in the terminal branches which is propagated along t he axon toward the soma. (C) 2001 Elsevier Science B.V. All rights reserved .