title: Recording of optic nerve spikes underwater from freely-moving horseshoe crab.
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D003386:Brachyura / Q000502:physiology*; D004566:Electrodes; D004594:Electrophysiology; D008722:Methods; D009900:Optic Nerve / Q000502:physiology*