Since light alone does not cause memory storage, if calcium is necessary and sufficient for memory storage, both light and turbulence must contribute to the calcium elevation. One experiment investigated the role of calcium release through the ryanodine receptor in classical conditioning. Dantrolene, which prevents the propagation of calcium waves, prevents in vitro classical conditioning of Hermissenda . This suggests that turbulence may cause a calcium wave from the terminal branches to the soma. Another experiment measured the characteristics of the light-induced currents.
Light stimulation activates two outward currents.
One is a fast, transient sodium current. The other is a slow, prolonged, closure of potassium currents. The latter current is blocked by Barium, and observed at membrane potentials close to resting, suggesting it may be a leak potassium current. Diffusion, calcium release, and biochemical reactions are implemented using Chemesis libraries written in this laboratory. A compartmental model was developed of the effect of turbulence on the type B photoreceptor of Hermissenda crassicornis.