Yours or mine? Ownership and memory

Abstract

An important function of the self is to identify external objects that are potentially personally relevant. We suggest that such objects may be identified through mere ownership. Extant research suggests that encoding information in a self-relevant context enhances memory (the so-called ‘self-reference effect’), thus an experiment was designed to test the impact of ownership on memory performance. Participants either moved or observed the movement of picture cards into two baskets; one of which belonged to self and one which belonged to another participant. A subsequent recognition test revealed that there was a significant memory advantage for objects that were owned by self. Acting on items (i.e., moving them) had no impact on memory. Results are discussed with reference to the importance of self-object associations in cognition.

Introduction

“A man’s Self is the sum total of all that he CAN call his, not only his body and his psychic powers, but his clothes and his house, his wife and children, his ancestors and friends, his reputation and works, his lands and horses, and yacht and bank-account”.

(James, 1890, p.291)

The ‘self’ is a dauntingly complex construct, but consideration of its ecological purpose suggests some very rudimentary functions. In particular, a ‘minimal’ sense of self (Gallagher, 2000) has been proposed that serves to distinguish an organism from its immediate external environment (Boyer et al., 2005, Gallagher, 2000, Humphrey, 2000, Neisser, 1988). As people interact with the environment, this minimal self is central to the experience of owning a body that produces actions and processes external stimuli. The concept of self can also be extended beyond the body, however, to incorporate aspects of the environment or experiences that are relevant to self (Belk, 1991). Indeed, the early development of strong self-object associations (manifested in the perpetual “Mine!” cry of young toddlers—see Fasig, 2000, Ross, 1996) speaks to the importance of ownership in cognition. The continual interaction between self and objects means that an important psychological function of the self may be to parse external stimuli into those items that are important for self to remember and those that can be treated lightly and processed less elaborately (see Tooby & Cosmides, 1995). The purpose of the present study was to investigate this proposed function by examining whether self-relevant objects are afforded a memory advantage.

The importance of self-relevance in item encoding is demonstrated by the ‘self-reference effect’ (SRE) in memory (Rogers et al., 1977, Symons and Johnson, 1997), the finding that information explicitly processed with reference to self (e.g., responding to the question “are you creative?”) enjoys a memory advantage over material encoded in relation to another person (e.g., responding to the question “is George Bush modest?”). The SRE has been attributed to the particularly accessible and elaborate nature of the self-construct, which enriches representations, improving both item recognition and source memory performance (see Johnson et al., 1993, Klein and Loftus, 1988, Mather et al., 2003, Mitchell and Johnson, 2000, Symons and Johnson, 1997). Although self-memory research to date has focused almost exclusively on trait encoding (see Symons & Johnson, 1997), we suspect that a memory advantage may also arise when self forms associations with objects that have been identified as self-relevant through less explicit means. If operating, of course, such an effect gives rise to an important question. How is self-relevance ascribed to stimuli?

In everyday life, the self is involved with objects in at least two important ways. The self can act on objects (e.g., “I pick up the apple”) and can form a psychological association with objects through ownership (e.g., “the apple is mine”). There is extant evidence to suggest that ownership in particular exerts a significant impact on cognition, although its effects on memory have not yet been explored. Owned objects are believed to enjoy a special processing status (Beggan, 1992) with such a strong association forming between self and owned objects that they are treated as psychological extensions of self and their perception is warped by pervasive self-protecting biases (Belk, 1988, Belk, 1991). This pattern is most clearly demonstrated by the ‘mere ownership’ effect, the tendency for objects arbitrarily assigned to self (i.e., owned but not chosen by self) to be imbued with more positive characteristics (Beggan, 1992, Belk, 1988, Belk, 1991) and to be perceived as more valuable (the endowment effect—Kahneman et al., 1991, Knetsch and Sinden, 1984) than identical items not assigned to self. Given these pervasive influences of ownership on cognition, its impact could be predicted to extend beyond evaluative processing to the encoding and storage of owned-object representations in memory. Thus, the first objective of the present study will be to explore the possibility that owned objects are afforded an advantage in memory.

Of course, to own an object one must first come in contact with the item in question. What, then, are the cognitive consequences of acting on (i.e., reaching out and making contact with) objects? Although there is an extensive literature detailing the memorability of self-produced actions (for review, see Tsakiris & Haggard, 2005), whether this effect extends to the product of the action (i.e., the object with which contact is made) is unknown. There is a clear ecological value of monitoring physical contact with the external environment (Boyer et al., 2005), and memory representations should be enhanced by the profusion of afferent and efferent signals elicited by reaching out and making contact with objects (see Blakemore et al., 1998, Blakemore and Frith, 2003, Farrer and Frith, 2002). Together, these qualities raise the possibility that acting on objects may enhance subsequent memory performance. As well as examining the memorial impact of self-object associations formed through ownership, the current study will also investigate the effect of self-object contact on memory performance.

To investigate these issues, we designed a shopping experiment in which participants owned and acted on external objects. Participants each moved stimulus items, placing half of the items in a basket owned by self and half in a basket owned by another participant. Memory for the items in the baskets was then assessed.