Ketamine acutely impairs memory consolidation and repeated exposure promotes stereotyped behavior without changing anxiety- and aggression-like parameters in adult zebrafish.
Physiology and Behavior January 18, 2022 Paula Michelotti, Francini Franscescon, T. E. Müller et al.
Ketamine, a dissociative anesthetic and drug of abuse, was tested in adult zebrafish to examine its effects on memory, anxiety, aggression, and stress. A single 20-minute exposure to a high concentration (40 mg/L) caused slight memory impairment in an avoidance task without affecting movement or anxiety. Repeated daily 20-minute exposures for seven days did not alter locomotion, aggression, anxiety-like behavior, or whole-body cortisol levels, but the highest concentration increased circling, a repetitive behavior. The findings suggest that acute ketamine disrupts memory, while repeated exposure may induce stereotyped behaviors without changing stress or social responses.