The "mere ownership effect" refers to individuals' tendency to evaluate objects they own more favorably than comparable objects they do not own. There are numerous behavioral demonstrations of the mere ownership effect, but the neural mechanisms underlying the expression of this self-positivity bias during the evaluation of self-associated objects have not been identified. The present study aimed to identify the neurobiological expression of the mere ownership effect and to assess the potential influence of motivational context. During fMRI scanning, participants made evaluations of objects after ownership had been assigned under the presence or absence of self-esteem threat. In the absence of threat, the mere ownership effect was associated with brain regions implicated in processing personal/affective significance and valence (ventromedial prefrontal cortex [vMPFC], ventral anterior cingulate cortex [vACC], and medial orbitofrontal cortex [mOFC]). In contrast, in the presence of threat, the mere ownership effect was associated with brain regions implicated in selective/inhibitory cognitive control processes (inferior frontal gyrus [IFG], middle frontal gyrus [MFG], and lateral orbitofrontal cortex [lOFC]). These findings indicate that depending on motivational context, different neural mechanisms (and thus likely different psychological processes) support the behavioral expression of self-positivity bias directed toward objects that are associated with the self.
Keywords: Mere ownership effect; Motivation; Self-enhancement; Self-esteem threat; Self-object associations.