不随意的・限定的・連続的に繰り返される音楽的イメージ(InLaCReMI): イヤワームが獲得する音楽的素材に関する理論とデータの整合性 Involuntary, Limited, and Contiguously Repeating Musical Imagery (InLaCReMI): Reconciling Theory and Data on the Musical Material Acquired by Earworms
Music & Science Published:April 3, 2023
“Earworms” have been proposed as a particular type of involuntary musical imagery (INMI) where musical material is repeated in the mind. The structure of the repetition is investigated by proposing a spreading activation model (SAM), where mental experience consists of priming and activation of nodes that represent objects, events, and relationships, including music. Music consists of chaining together nodes representing small music segments within hierarchical structures. Listening to music at a point in time activates the music’s represented segment, which then primes the node representing the segment that follows. Repeating musical segments are coded recursively, with an additional layer of “context” nodes tracking global, structural location. From this basis, two hypotheses were proposed: H1 “Contiguous repetition at encoding” and H2 “Low environmental focus.” H1 predicts that when an INMI episode is a contiguously repeating segment, it must be based on music that contains contiguous repetition: it will be perceived as a subset of INMI – involuntary, limited, and contiguously repeating musical imagery (InLaCReMI). H1 challenges current views about preferred segments for looping, such as the “hook” of a tune. H2 predicts that InLaCReMI occurs when an individual is not focused on the immediate environment. In such a state there is less social imperative to activate high attentional-demand contextual information and so adherence to contextual integrity in thought is relaxed, leading to looping of recurrently activated nodes that were encoded with contiguous repetition. Additional predictions were made using SAM, demonstrating the potential for SAM to provide a unifying understanding of INMI. InLaCReMI is proposed as a frequently occurring species of INMI and confirmation of this phenomenon through more structured empirical investigation will provide novel insights into mental operation, and the nature of INMI.