Cultural background shapes the ownership-based self-reference effect

Abstract

Ownership pervasively shapes our interactions with objects according to a complex set of social norms, and as such we frequently encode objects in the context of ownership. In their seminal study, Cunningham et al. (2008) experimentally assigned ownership of objects to participants during an object-sorting task. In a surprise recognition memory test following this encoding task, recognition rates were higher for self-owned objects compared with objects owned by others. This ownership-based self-reference effect is thought to be an instantiation of more general self-related processing biases. Substantial evidence indicates that self-related processing biases vary as a function of culture in tasks that do not involve ownership. Participants with Western cultural backgrounds typically show performance advantages for self-associated stimuli compared with stimuli associated with both non-close others (e.g., strangers) and close others (e.g., family members), whereas participants with Asian cultural backgrounds show self-bias only relative to stimuli associated with non-close others. The goal of this thesis was to investigate whether there are parallel cultural differences in the ownership-based self-reference effect.In Chapter 1, I provide a broad overview of the above topics as context for the experimental studies that follow. All experiments in this thesis used a computerised adaptation of Cunningham and colleagues' (2008) ownership-based self-referential memory paradigm. For each participant, the other-referent was either a non-close other (i.e., a stranger) or a close other (i.e., participants' mother). In Chapter 2, I describe a two-experiment study comparing participants with Western and Asian cultural backgrounds. Attentional engagement with objects during the encoding task was not task-necessary in Experiment 1 but was task-necessary in Experiment 2. In both experiments and regardless of the type of other-referent, Western-background participants recognised self-owned objects at a higher rate than other-owned objects. Although these data are consistent with an independent representation of self for Western-background participants, the magnitude of the ownership effect was relatively small compared with previous studies conducted in Western countries. Asian-background participants showed ownership effects in Experiment 2 but not Experiment 1, which suggests that cultural differences in attentional strategy influence whether objects are encoded with respect to ownership. Ownership effects for Asian-background participants in Experiment 2 were broadly consistent with an interdependent representation of self. Specifically, recognition rates were higher for self-owned relative to stranger-owned objects, but lower for self-owned relative to mother-owned objects.In Chapter 3, I aimed to replicate the results of Chapter 2, Experiment 2 in a single experiment with high statistical power. Results for Asian-background participants aligned closely with Chapter 2, Experiment 2, except that recognition rates for mother-owned and self-owned objects did not differ significantly. Western-background participants, however, showed no significant ownership effects. The Western-background groups in Chapters 2 and 3 predominantly consisted of Anglo-Australian participants. I discuss the possibility that the atypically small (Chapter 2) or absent (Chapter 3) ownership effects reflect cultural differences between the Anglo-Australian participants in the current studies and participants in previous studies conducted in the United Kingdom, the United States of America, and Germany. Additionally, in line with most previous studies, in Chapters 2 and 3 I measured memory performance in terms of corrected hit rates. Corrected hit rates are determined by a combination of memory trace strength and decisional bias, and either of these factors could be the source of the unexpected results for the Western-background group. My secondary aim in Chapter 3 was to investigate whether within-culture variability in ownership effects was associated with within-culture variability in independence and interdependence, but I found no evidence of any such relationships.In Chapter 4, I present a single-experiment study of female, Anglo-Australian participants in which I used signal detection theory to derive separate measures of memory trace strength and decisional bias. No ownership effects emerged in recognition sensitivity, which specifically relates to memory trace strength. Consistent with the possibility that ownership-related memory differs between Anglo-Australian participants and participants from other Western cultures, these data contrast with a new study reporting a self-owned advantage in recognition sensitivity for United Kingdom participants (Collard et al., 2020). Anglo-Australian participants, however, did show evidence of ownership-related decisional biases in the memory test. Participants adopted a more conservative recognition criterion for self-owned objects compared with other-owned objects, especially when the other-referent was the mother.In Chapter 5 (General Discussion), I discuss three key implications of the current data and corresponding directions for future research. First, ownership can influence object memory not only by modulating memory trace strength, but also via decisional biases in the memory test. Second, cultural differences in the representation of self and in attentional strategy may moderate ownership effects in both memory trace strength and decisional bias. Third, cultural differences in ownership-related memory exist not only between Western and Asian cultures, but also within these broad categories.