Effects of word-level alliteration on subjective evaluation of Japanese pseudo-poem

Alliteration is a poetic technique in which the initial sounds of words or lines are repeated. In Western languages, the psychological effects of alliteration have been widely investigated. For instance, Lea et al. (2008) demonstrated that alliterative phrases are recognized more quickly than non-alliterative ones, and Davis et al. (2016) reported that alliterative promotional slogans enhance perceived likability and purchase intentions. These findings suggest that alliteration facilitates memory and emotional impressions. Although the psychological effects of alliteration in Japanese have rarely been studied, Yoshio and Kambara (2025) examined its influence using both traditional and pseudo-Japanese poems. They found no significant differences in preference or perceived beauty between alliterative and non-alliterative stimuli. However, in terms of arousal, alliterative poems were rated as more exciting than their non-alliterative counterparts when presented pseudo-poems. Notably, the previous study manipulated alliteration at the consonant level in a line-for-line format, which may have made it difficult for native Japanese speakers to detect the alliterative pattern. Considering that the mora, rather than the consonant, is the basic phonological unit in Japanese (Otake et al., 1993), this methodological choice may have limited the detectability of alliteration. The present study aims to explore the effect of word-for-word alliteration on the impression of pseudo-Japanese poems among native Japanese speakers. We employ three conditions: (1) alliteration based on the mora unit (mora-alliteration condition), (2) alliteration based on the consonant unit (consonant-alliteration condition), and (3) a non-alliterative control condition (no-alliteration condition). Participants will rate each poem on multiple scales, including beauty, preference, and arousal. These scales are selected based on previous studies on impression and kansei value (e.g., Chaudhuri et al. 2024; Menninghaus et al., 2015). This study aims to clarify how phonological features—specifically alliteration—affect aesthetic and emotional impressions in Japanese poetry.