The irrelevant-speech effect (ISE) is a laboratory phenomenon in which performance at memory recall is impaired by the presence of irrelevant auditory stimuli during the initial encoding phase. In a typical ISE experiment, participants are asked to remember a sequence of letters presented visually (e.g. F, K, L, M, Q, R, Y in a shuffled random order between trials) while irrelevant speech is played over headphones. The typical finding is that recall performance is impaired by the presentation of speech compared with silence. The ISE has been influential in cognitive psychology, prompting the advancement of two broad classes of competing explanations: one in which the irrelevant sounds gain automatic access to memory processes without any specified role for attentional selection, and another in which the ISE is explained by irrelevant speech drawing attention away from the relevant items to be recalled.

 

In the current study, Kattner et al. (2023) propose a replication of a seminal study by Jones and Macken (1995) that provided a foundation for the automatic access (or ‘interference-by-process’) class of theories. In their original set of experiments, Jones and Macken reported that the segregating individual components of the irrelevant speech (the spoken letters V, J, and X) into different lateralized locations reduced the magnitude of the ISE by converting a single ‘changing-state’ stream three separate ‘steady-state’ streams. Here, Kattner et al. ask firstly whether this classic finding can be successfully replicated in a well-powered sample, and secondly whether the streaming-by-location effect in Jones and Macken reduces the ISE to the same level as observed during a steady-state baseline condition in which a single letter is repeated from each location. If the answer to either question is No then doubts will have been raised about interference-by-process theories, opening the door (even more) to alternative theoretical explanations of the ISE.
 

The Stage 1 manuscript was evaluated over two rounds of in-depth review. Based on detailed responses to the reviewers' comments, the recommender judged that the manuscript met the Stage 1 criteria and therefore awarded in-principle acceptance (IPA).

 

URL to the preregistered Stage 1 protocol: https://osf.io/2tb8e
 
Level of bias control achieved: Level 6. No part of the data or evidence that will be used to answer the research question yet exists and no part will be generated until after IPA.
 
List of eligible PCI RR-friendly journals:
 

 

1. Jones, D. M. & Macken, W. J. (1995). Organizational factors in the effect of irrelevant speech: The role of spatial location and timing. Memory & Cognition, 23, 192–200. https://doi.org/10.3758/BF03197221 

 
2. Kattner, F., Hassanzadeh, M. & Ellermeier, W. (2023). The role of spatial location in irrelevant speech revisited: A registered replication of Jones and Macken (1995). In principle acceptance of Version 3 by Peer Community in Registered Reports. https://osf.io/2tb8e