Expra FS23 - Hebb (Items repeated at odd positions)
Creators: name: Weimer, Elin
name: Bartsch, Lea Maria
name: Marucci, Debora Sara
name: Musfeld, Philipp
name: Degiorgi, Lisa
Publisher: name: Open Science Framework
Year: 2023
Subjects: subject: Psychology
subject: FOS: Psychology
subject: Social and Behavioral Sciences
subject: Cognitive Psychology

description: A classic experimental phenomenon to study learning by repetition is the Hebb effect. This effect describes the increasingly better performance of participants at immediate serial recall of a repeatedly presented list presented among trials of non-repeated lists. This shows that people can build up long-term memory for the repeated list through repetition. Several mechanisms have been proposed to explain the learning effect and how individuals represent sequences of stimuli: the idea of chaining, which relies on the reinforcement of associations between suc-cessive items (Jones, 1993); item-position associations, in which each item is associated to its relative position in the list (Henson, 1998); chunking, in which items from a repeated list are integrated into a unit (Burgess &amp; Hitch, 2006; Page &amp; Norris, 2009). These three explanations were investigated experimentally by Fastame et al. (2005) using different list structures. To test the chaining approach, conditions were created in which the same sequence of items were repeated but always presented at different positions within the list. To test pure item-position associations, lists were created in which only every second item was repeated, and thus item-position associations were repeated without item-item associations. In both conditions, there was no learning effect, which provides evidence against both chaining and item-item associations alone. Thus, according to the findings, serial sequence learning must rely on a combination of multiple cues, which could be a combination of chunking and item-position associations (Fastame et al., 2005). Evidence against the idea of chunking, however, comes from studies in which the Hebb effect was investigated in the complex-span task. In the complex-span task, encoding and/or retrieval of items is disrupted by distractors, so that the formation of an integrated unit of sequence is interrupted. However, contrary to the idea of chunking, a Hebb effect was still shown here (Araya et al., 2022, 2023; Oberauer et al., 2015). However, further findings from the studies of Araya et al. (2022, 2023), which show a transfer of the learning effect from complex span to simple span tasks and vice versa, challenge this criticism and rather argue for a common underlying learning mechanism. Now the question arises why lists in which items are interrupted by distractors can be learned (complex span; Araya et al. 2022; 2023), but not lists in which only every second item is repeated (simple span; Fastame et al. 2005). One proposed explanation would be that the distractors are removed from the representation of the list in working memory and thus learning could still be caused by a type of chunking (Araya et al., 2023). Subjects may not have been aware in the Fastame et al. (2005) study that every other item was repeated and thus could not recognize the structure being learned. This explanation is consistent with recent findings from the Musfeld et al. (2022) study. In this study, awareness of list repetition was considered and it was found that learning actually began when individuals were aware of repetition. Given these findings, an open question is how one can promote awareness of repetition in partially repeated lists (every other item, at the odd positions) in order to produce a learning effect. With our experiment we want to find out if we can promote awareness of repetition in partially repeated lists (every other item, at the odd positions) in order to produce a learning effect. Specifically, with our manipulation we want to discover whether spatial grouping of the repeated items in the Hebb-list as well as coloring their frame in red, can sufficiently promote awareness about their repetition and in the end lead to a learning effect. This research question is relevant because it could help to find out whether awareness about the repetition is the crucial mechanism underlying the ability to learn only partially repeated lists. Furthermore, this study can contribute to the understanding of working memory and how memory and learning processes work.