Adaptation of Feeding Sequences in Aplysia Oculifera to Changes in the Load and Width of Food

In Aplysia oculifera, we examined how feedback from foods of differing physical characteristics produces feeding sequences that are appropriate to the food. Animals were fed strips of food systematically modified by attaching weights to the end of the strip or by changing the width of the strip. Both changes led to an increase in inter-swallow interval and a decrease in the amount of food that entered the mouth per swallow. These data indicate that the oscillator setting swallowing frequency is affected by feedback, but that the amplitude of swallowing movements may not be regulated by feedback. Some swallows led to partial or complete cutting of the food. In some cases, cutting led to loss of contact and release of the food. When cutting releases food, its function is apparently to prevent food that has already been swallowed from being pulled out of the mouth. Cutting food may also serve additional functions.