Neural basis of ambiguity and aesthetic experience in haiku poetry: An fMRI study

Although neuroaesthetics has extensively examined visual art and music, the neural mechanisms underlying poetic appreciation remain less explored. This fMRI study investigated how the brain processes ambiguity and aesthetic experiences using haiku, the world’s shortest form of poetry. Originating in Japan, haiku is characterized by extreme brevity, often omitting information to compel readers to generate mental imagery and confront inherent ambiguities. Thirty-nine participants read haiku, which was pre-categorized via an independent survey into high- and low-ambiguity conditions, and rated its beauty inside the scanner. Consistent with previous findings, the behavioral results indicated a preference for low-ambiguity haiku. Neuroimaging revealed that reading low-ambiguity haiku, compared to high-ambiguity ones, elicited greater activation in the posterior cingulate cortex and left inferior parietal lobule including the angular gyrus. These regions are associated with the default mode network and semantic integration, suggesting that interpretable poems facilitate stronger self-referential processing and scene construction. Higher beauty ratings were significantly associated with increased activation in the primary visual cortex. Our findings imply that the aesthetic appeal of haiku depends on semantic accessibility, where reduced ambiguity facilitates self-referential simulation via the default mode network, leading to vivid perceptual encoding in the visual cortex.