Attentional and evaluative biases help people maintain relationships by avoiding infidelity.

Two longitudinal studies of 233 newlywed couples suggest that automatic attentional and evaluative biases regarding attractive relationship alternatives can help people maintain relationships by avoiding infidelity. Both studies assessed participants' tendency to automatically disengage attention from photos of attractive, opposite sex individuals; one study assessed participants' tendency to devalue those individuals by comparing their attractiveness evaluations to evaluations made by single people, and both studies assessed infidelity and relationship status multiple times for approximately three years. Several sources of devaluation emerged, but only participants' history of short-term sex predicted both biases; having more short-term sexual partners was associated with being slower to disengage attention from attractive alternatives, and, among men, evaluating such individuals more positively. In turn, both processes exerted indirect effects on relationship dissolution by predicting infidelity; being 100 ms faster to disengage attention from attractive alternatives or rating them 2 scale points lower in attractiveness was associated with a decrease in the odds of infidelity of approximately 50%; the effect of devaluation on infidelity was stronger among participants who evidenced steeper declines in marital satisfaction. These associations emerged because unfaithful individuals took longer to disengage attention from attractive alternatives compared with other social targets and did not differ from singles in their evaluations of those alternatives. Among several other predictors of infidelity, partner attractiveness was associated with a decrease in the odds of infidelity among men but not women. These findings suggest a role for basic psychological processes in predicting infidelity, highlight the critical role of automatic processes in relationship functioning, and suggest novel ways to promote relationship success. (PsycINFO Database Record (c) 2018 APA, all rights reserved).