Nervous system of gastropods

[1] The brain of a gastropod consists of three pairs of ganglia, all located close to the oesophagus and forming a nerve ring around it.

The cerebral ganglia are located above the oesophagus and supply nerves to the eyes, tentacles, and other sensory organs in the head.

The main nerve cords of the central nervous system run through the length of the body from the pleural ganglia.

In the ancestral gastropod, these would presumably have run down either side of the animal, but because of the torsion of the visceral mass found in many modern forms, they now cross over each other.

In air-breathing freshwater snails of the genus Lymnaea Lamarck, 1799 goal-directed decision-making during the hunt for food is performed by just two neuron types.