Intimacy, concreteness, and the "self-reference effect".

Reference to oneself during incidental learning of words frequently results in better recall performance than reference to other persons. However, this effect occurs under different conditions with differing strength, and sometimes it is even reversed. Meta-analyses and further experimental studies suggest that increased recall performance under a self-referential encoding task occurs only if it is compared with a nonintimate other person and if abstract material is presented, irrespective of the type of previously presented words (adjectives or nouns). In the current paper, two experiments are reported which support the assumption that this intimacy effect on memory only occurs if no pictorial or concrete features of the material (nouns) to be learned can be exploited for an improvement in encoding or remembering the material. All results agree with predicted effect sizes, which were drawn from a meta-analysis and subsequently conducted experimental studies. This suggests that a recall advantage of referring to oneself compared to other persons is subordinate to the effects of concreteness or imageability. Moreover, the current results offer a theoretical explanation of some previously reported but nevertheless puzzling results from imagery instructions, which indicate decreased recall performance for self-reference compared to other-reference.