The negative-state relief model states that human beings have an innate drive to reduce negative moods. They can be reduced by engaging in any mood-elevating behaviour, including helping behaviour, as it is paired with positive value such as smiles and thank you. Thus negative mood increases helpfulness because helping others can reduce one's own bad feelings.[1]
- ^ Baumann, D. J.; Cialdini, R. B.; Kenrick, D. T. (1981). "Altruism as hedonism: Helping and self-gratification as equivalent responses". Journal of Personality and Social Psychology. 40 (6): 1039–1046. doi:10.1037/0022-3514.40.6.1039.