چیزی که ERP در مورد اثر نسبی به ما می گوید What can ERPs tell us about the generation effect?

1. Introduction Over the years, an important aim of research on memory has been to determine the conditions that can help improve memory performance. The generation effect is the phenomenon whereby an individual typically remembers more easily an item that has been produced by him/herself during encoding than one that has been externally presented [1]. In the classic paradigm, participants are asked to memorize a list of items under two conditions. Some of these to-be-remembered items are provided by the experimenter in their complete form (read condition; e.g. LEAF-VEGETABLE), while for the others, participants have to generate the target item from a semantically or phonologically related cue (generate condition; e.g. LEAF-VEGET__). The better performance when generating than reading has been demonstrated in a wide range of generation tasks, with different kinds of material, and their benefits have been proven in both healthy adults and neurological patients [see 2 for a review]. Several hypotheses have been suggested to explain the cognitive mechanisms involved in the generation effect. Some authors have argued that self-generated materials are remembered better because generation requires the use of processing resources and thus involves more effortful cognitive processes [3, 4, 5, 6]. For instance, Taconnat et al. [5] demonstrated that the generation effect of rhymes was related to an executive composite score, suggesting that this encoding strategy is strongly dependent on executive functioning abilities. Another explanation that has been put forward is based on the depth-of-processing model [7] and suggests that generating the target leads to deeper (i.e. semantic) processing and thus to a higher level of memory performance than simply encoding items passively. More precisely, some researchers have suggested that the generation effect may be due to the enhancement of lexical or semantic activation when the target item is self-generated [8].