Modulaciones Poligénicas de los Efectos Señuelo y Compromiso por los Sistemas Dopaminérgico y Serotoninérgico

Decoy effect and compromise effect are context-dependent choice biases in which adding an option shift preferences without changing the original alternatives. The decoy effect increases preference for a target by introducing an inferior comparison, whereas the compromise effect reflects a tendency to choose intermediate options. Given the established roles of dopaminergic and serotonergic pathways in reward motivation and behavioral inhibition, this study investigated whether polygenic risk scores (PRSs) within these neurotransmitter pathways predict these two effects. Two independent samples of Chinese university students were recruited from Luoyang (Sample 1: N = 647) and Xi'an (Sample 2: N = 569), providing a demographically homogeneous population for assessing genetic contributions to decision biases. In the serotonergic system, the PRS significantly predicted compromise effect in both samples (Sample 1: β = 0.093, p = 0.017; Sample 2: β = 0.094, p = 0.026) and decoy effect in Sample 2 (β = 0.122, p = 0.003). In the dopaminergic system, the PRS only significantly predicted compromise effect in Sample 2 (β = 0.132, p = 0.002), while it significantly predicted decoy effect in both samples (Sample 1: β = 0.132, p = 0.001; Sample 2: β = 0.126, p = 0.003). Combined-sample analyses confirmed a unique contribution of dopaminergic PRS to the compromise effect and showed that the decoy effect is jointly influenced by dopaminergic and serotonergic pathways. These results show that decoy and compromise effects arise from distinct genetic mechanisms: dopamine amplifies relative reward signals driving decoy choices, whereas serotonin promotes safer, intermediate preferences underlying compromise decisions.