Barker, S. B., Rasmussen, K., & Best, A. M. (2003). Effect of Aquariums on Electroconvulsive Therapy Patients. Anthrozoos, 16(3), 229-240.

This study investigates the effect of an aquarium on pre-treatment anxiety, fear. frustration, and depression in electroconvulsive therapy (ECT) patients. Forty-two patients consecutively referred for ECT were rotated between rooms with and without aquariums. Self report measures of depression, anxiety, fear, and frustration were obtained along with heart rate and blood pressure. Preliminary analysis of variance revealed no significant differences between the aquarium and control conditions on any of the dependent measures. A trend toward significance was found for self reported anxiety (p = .08) and further data was collected. Subsequent analysis of variance showed no significant difference (p = .10) in anxiety between the aquarium and control condition. Factoring out demographic factors, the average subject experienced 8% less anxiety (p = .10) in the presence of an aquarium.