Music influences the content of spontaneous thought

Spontaneous thought is a form of cognition that is relatively unconstrained and free flowing. Recent accounts have raised the possibility that the generation and content of spontaneous thought can be influenced by even weak perceptual constraints. We leveraged this perspective to develop an approach using music, a ubiquitous stimulus that permeates our everyday environments, as a window into the mechanisms that shape spontaneous thought content. Adults spanning four age groups listened to music from ten different genres and completed the open-ended task of writing descriptions of any thoughts that arose. Natural language processing analysis was applied to obtain computational similarity (word2vec) of the semantic meaning of thought descriptions. We found that thoughts sustained while hearing music from the same genre shared greater semantic similarity than those sustained while hearing music from different genres, and participants from the same age group experienced more similar thoughts than those from different age groups. Properties that varied naturally with genre, including the music's auditory features, expressed emotions, and contextual associations, all contributed significantly to explaining the greater semantic similarity of thoughts within genres. These results demonstrate that spontaneous thought can be jointly shaped by perceptual and experiential constraints, opening new avenues for understanding when and why particular thoughts come to mind, with implications for creativity and mental health.