EN
Recent research has shown that pharmacological enhancement of dopaminergic function by acute administration of L-DOPA increases an optimism bias in humans. In the present study, we investigated whether L-DOPA have similar effects in rats. To accomplish this goal, the animals were trained in the ambiguouscue interpretation (ACI) paradigm. In this paradigm the rats must press one lever in response to one tone to receive a reward and to press another lever in answer to a different tone to avoid punishment. Cognitive judgment bias is than tested by measuring the pattern of animals‘ responses to a tone of intermediate frequency (ambiguous-cue). After initial behavioral training, the rats received single injections of L-DOPA and were subsequently tested with the ACI paradigm. The drug was administered in 3 doses using a fully randomized Latin square design. Control animals received injections of physiological saline. L-DOPA at all tested doses (2, 4 and 8 mg/kg, co-administered with benserasidine 12.5 mg/kg) significantly biased animals towards negative interpretation of the ambiguous cue. The results are discussed in relation to human studies. Supported by the National Science Centre (Research grant: Sonata bis dec-2012/07/E/NZ4/00196) and the statutory funds of the Institute of Pharmacology PAS.