Related Experiment Video
Updated: Apr 25, 2026
Developing a Rat Model for Bipolar Disorder
Published on: May 2, 2025
Cognitive judgment bias in the psychostimulant-induced model of mania in rats
Rafal Rygula1, Ewa Szczech, Jakub Kregiel
1Affective Cognitive Neuroscience Laboratory, Department of Behavioral Neuroscience and Drug Development, Institute of Pharmacology Polish Academy of Sciences, 12 Smetna Street, 31-343, Krakow, Poland, rygula@gmail.com.
Rationale:
Animal models of mania lack genuine cognitive parameters. The present gold standard of mania models, amphetamine-induced hyperlocomotion, is rather unspecific and does not necessarily target its cardinal symptoms. Therefore, alternative behavioral markers that are sensitive to stimulants are required.
Objectives:
In the present study, by combining the psychostimulant-induced model of mania in rodents with the recently developed ambiguous-cue interpretation (ACI) tests, we investigated the effects of chronic administration of D-amphetamine and cocaine on the cognitive judgment bias of rats.
Methods:
To accomplish this goal, in two separate experiments, previously trained animals received chronic, daily injections of either D-amphetamine (2 mg/kg) or cocaine (10 mg/kg) for 2 weeks and were subsequently tested with the ACI procedure.
Results:
Chronic treatment with both psychostimulants did not make rats more "optimistic."
Conclusions:
The results are discussed in terms of behavioral and pharmacological actions of the tested compounds and their implications for modeling mania in animals.
