Behaviour 2019
Effect of Serotonin Transporter Deficiency on the Cognitive Judgment Bias of Mice
Viktoria Krakenberg1,2, Edith Ossendorf1, Sylvia Kaiser1,2, Norbert Sachser1,2, S. Helene Richter1,2. 1University of Muenster, Muenster, , Germany; 2Otto Creutzfeldt Center for Cognitive and Behavioral Neuroscience, Muenster, , Germany

In humans, there is a common polymorphism in the regulatory region of the serotonin transporter (5-HTT) gene with a long and a short allelic variant. Carrying the short allele has been linked to a higher risk of developing anxiety disorders, depression, and more recently also to the persistence of negative cognitive biases. 5-HTT knockout mice, lacking either one or two copies of the 5-HTT gene, provide a well-established mouse model for the human psychopathological symptoms. Using a newly implemented, translational touchscreen task, we aimed to investigate, whether 5-HTT deficient mice also display a more negative cognitive bias, and whether this coincides with higher levels of anxiety-like behavior. While 5-HTT knockout mice showed highest levels of anxiety-like behavior compared to heterozygous and wildtype mice, most surprisingly, no differences regarding cognitive judgment bias (CJB) were found between the three genotypes. The results confirm previous findings reporting a robust effect of 5-HTT genotype on the animals’ anxiety-like phenotype. Furthermore, our data suggest additional factors to play a role in the modulation of CJB in mice.