Examining the sex- and circadian dependency of a learning phenotype in mice with glycine transporter 1 deletion in two Pavlovian conditioning paradigms

► Forebrain neuronal deletion of glycine transporter 1 enhances Pavlovian conditioning. ► Its robust expression across sexes, circadian phases and paradigms is tested here. ► The effect size is shown to be strongest in female mice tested in the dark phase. ► The phenotype is also associated with sex-dependent effects on extinction & anxiety. ► Here, we set a new standard of exactitude in behavioural phenotyping.