The purple sea urchin, Strongylocentrotus purpuratus, has been extensively studied for its developmental and reproductive characteristics, but knowledge regarding the neurobiology of the adult sea urchin is lacking. Specifically, the understanding of the different neurotransmitters involved in the systems controlling sea urchin behavior are widely under-researched. To further investigate the neurotransmitter systems and their implications in sea urchin behavior and locomotion, we have conducted behavioral and motility assays. The behavioral assay employs a righting response, in which a sea urchin is inverted and the amount of time for the urchin to right itself with the use of its spines and tube feet is recorded. Righting assays were performed following drug exposure via immersion in varying concentrations of propranolol, isoprenaline, or bicuculline. In vivo administration of propranolol, a beta-adrenergic receptor antagonist slowed the righting response of the sea urchins in a dose-dependent manner (IC50 = 39.8 μM). When the beta-adrenergic receptor agonist isoprenaline, and propranolol were administered together, isoprenaline was not able to reverse the effects of propranolol, and in fact isoprenaline actually slowed the righting response at high concentrations (IC50 = 400 μM). Bicuculline, a GABAA antagonist, had no significant effect on the righting response up to 100 μM, but did visibly increase tube feet motility. The effect of bicuculline on tube feet motility led to the development of a motility assay. The motility assay utilizes a small tank in which sea urchins are isolated following drug immersion, and Behavioral Observation Research Interactive Software (BORIS) will be used to analyze the video footage of tube feet movement. The motility assay will quantitatively measure tube feet motility in response to drug exposure.