Learn More
The anatomical organization of the olfactory system of terrestrial snails and slugs is described in this paper, primarily on the basis of experiments using the African snail Achatina fulica. Behavioral studies demonstrate the functional competence of olfaction in mediating food finding, conspecific attraction, and homing. The neural substrate for olfaction(More)
The tentacles of the terrestrial snail Achatina fulica contain an epithelium at their tips which is specialized for olfaction. The histology of the snail's olfactory organ bears a striking resemblance to that of the olfactory mucosa in the nose of vertebrates, where the receptor cell population is known to undergo a continuous process of renewal. In the(More)
The tentacle withdrawal reflex in the terrestrial snail Helix aspersa involves bending and retraction of the tentacles. When elicited by mechanical stimulation of the tentacle, the reflex is mediated by the conjoint action of the central and peripheral nervous systems. The neural circuit underlying the stimulus-response pathways was studied in vitro using a(More)
We have investigated the role of the right mesocerebrum in the expression of mating behaviour in the garden snail Helix aspersa. Using an in vivo stimulation and recording technique, we provide evidence for both sensory and motor functions in the mesocerebral neuronal population. Some neurones were specifically sensitive to tactile stimuli delivered to the(More)
The morphology and dendritic organization of corticocortical neurons in the superficial layers of area 18 that project to area 17 were studied by intracellular injection of lucifer yellow in the fixed-slice preparation. This corticocortical population contains primarily standard pyramidal cells, but occasional nonpyramidal, modified, fusiform, star, and(More)
The giant cerebral neuron (GCN) is a serotoninergic cell that facilitates feeding behaviour in gastropod molluscs. We have examined the morphology of its cerebral arborizations after labelling them by intracellular injection of hexamminecobalt. Observations in the light microscope reveal extensive arborizations, with similar overall distributions, in the(More)
Because oviposition in the land snail Helix aspersa is a metabolically expensive process coupled to a high fixed cost, one expects oviposition to occur only when the clutch size surpasses a minimum value at which the reproductive benefit exceeds the cost. We propose that neural innervation of the gonad allows H. aspersa to monitor oocyte production and(More)
The procerebrum is an olfactory processing region that occupies approximately one-third of the total brain area in pulmonate gastropod molluscs. It has many unusual features, including a development separate from the rest of the brain and the absence of axons belonging to its intrinsic neurons. We have investigated the input and output pathways of the(More)
The beating activity of the molluscan heart is myogenic, but it is influenced by nervous signals of central origin. Previous studies have demonstrated changes in cardiac output during feeding and other behaviors. Here, we describe a short latency, transient cardiac response that accompanies withdrawal reflexes. When evoked by electrical stimulation of(More)
The snail tentacle ganglion is a prominent structure that innervates an epithelial pad sensitive to wind and odors. Its neural composition, and that of the sensory pad, was studied in the terrestrial snail Achatina fulica by applying horseradish peroxidase to the distal end of the cut tentactle nerve. Five types of neurons were labelled by the procedure:(More)