The role of anterior ganglia in phototaxis and thigmotaxis in the earthworm

Abstract

The role of the supra- and subpharyngeal (anterior) ganglia in thigmotaxic and phototaxic behavior in the earthworm (Lumbricus terrestris) was studied. In the first experiment, thigmotaxis reduced negative phototaxis for both worms whose anterior ganglia were removed and control worms. Therefore, the thigmotaxic effect appeared independent of the anterior ganglia. In the second experiment, the role of the anterior ganglia in the accuracy of escape from a directional light was studied. Earthworms with intact anterior ganglia did not escape the light significantly more accurately than earthworms without anterior ganglia. © 1972, The Psychonomic Society, Inc.. All rights reserved.