Music tends to be highly repetitive, both in terms of musical structure and in terms of listening behavior, yet little is known about how engagement changes with repeated exposure. Here we postulate that engagement with music affects the inter-subject correlation of brain responses during listening. We predict that repeated exposure to music will affect engagement and thus inter-subject correlation. Across repeated exposures to instrumental music, inter-subject correlation decreased for music written in a familiar style. Participants with formal musical training showed more inter-subject correlation, and sustained it across exposures to music in an unfamiliar style. This distinguishes music from other domains, where repetition has consistently been shown to decrease inter-subject correlation. Overall, the study suggests that listener engagement tends to decrease across repeated exposures of familiar music, but that unfamiliar musical styles can sustain an audience’s interest, in particular in individuals with some musical training. Future work needs to validate the link proposed here between music engagement and inter-subject correlation of brain responses during listening.

The speech-to-song illusion (Deutsch et al., 2011) tracks the perceptual transformation from speech to song across repetitions of a brief spoken utterance. Because it involves no change in the stimulus itself, but a dramatic change in its perceived affiliation to speech or to music, it presents a unique opportunity to comparatively investigate the processing of language and music. In this study, native English-speaking participants were presented with brief spoken utterances that were subsequently repeated ten times. The utterances were drawn either from languages that are relatively difficult for a native English speaker to pronounce, or languages that are relatively easy for a native English speaker to pronounce. Moreover, the repetition could occur at regular or irregular temporal intervals. Participants rated the utterances before and after the repetitions on a 5-point Likert-like scale ranging from “sounds exactly like speech” to “sounds exactly like singing.” The difference in ratings before and after was taken as a measure of the strength of the speech-to-song illusion in each case. The speech-to-song illusion occurred regardless of whether the repetitions were spaced at regular temporal intervals or not; however, it occurred more readily if the utterance was spoken in a language difficult for a native English speaker to pronounce. Speech circuitry seemed more liable to capture native and easy-to-pronounce languages, and more reluctant to relinquish them to perceived song across repetitions.

Instrumental music can seem to tell engrossing stories without the use of words, but it is unclear what leads to this narrativization. Although past work has investigated narrative responses to abstract moving shapes, very little work has studied the emergence of narrative perceptions in response to nonlinguistic sound. We measured narrative responses to wordless Western and Chinese music in participants in the US and in a cluster of villages in a rural part of China using a Narrative Engagement (NE) scale developed specifically for this project. Despite profound differences in media exposure, musical habits, and narrative traditions, narrative listening was employed by many participants and associated with enjoyment in both groups; however, the excerpts that unleashed this response were culturespecific. We show that wordless sound is capable of triggering perceived narratives in two groups of listeners with highly distinct patterns of cultural exposure, reinforcing the notion that narrativization itself is a readily available mode of experiencing music. The particular sounds that trigger narrativization, however, rely on enculturation processes, as demonstrated by the within-culture consistency, but between-culture divergence in the specific excerpts that led to narrative engagement. Narratives can emerge in multiple modalities, including wordless sound, but association patterns specific to individual cultures critically shape how apparently abstract sound patterns come to acquire deep meaning and significance to people.

This study investigated the role of repetition on listener response. It tested the hypothesis that repetition, in the form of looping during an exposure phase, would make random sequences of tones sound more musical when rated later during a test phase. In Experiment 1, participants without special music training rated the musicality of random sequences of tones on a Likert-like scale from 1 to 7. Experiment 2 used the highest and lowest rated sequences as stimuli. In an initial exposure phase, participants heard half these sequences presented six times in a loop, and half of them presented only once. In a subsequent test phase, they rated the musicality of each sequence. Sequences that had been repeated were rated as more musical, regardless of whether they had received a high or low musicality rating in Experiment 1, but the effect size was small. These results, although limited in some respects, support a large body of literature pointing to the importance of repetition in aesthetic experiences of music.

A growing number of studies are investigating the way that aesthetic experiences are generated across different media. Empathy with a perceived human artist has been suggested as a common mechanism [1]. In this study, people heard 30 s excerpts of ambiguous music and poetry preceded by neutral, positively valenced, or negatively valenced information about the composer's or author’s intent. The information influenced their perception of the excerpts—excerpts paired with positive intent information were perceived as happier and excerpts paired with negative intent information were perceived as sadder (although across intent conditions, musical excerpts were perceived as happier than poetry excerpts). Moreover, the information modulated the aesthetic experience of the excerpts in different ways for the different excerpt types: positive intent information increased enjoyment and the degree to which people found the musical excerpts to be moving, but negative intent information increased these qualities for poetry. Additionally, positive intent information was judged to better match musical excerpts and negative intent information to better match poetic excerpts. These results suggest that empathy with a perceived human artist is indeed an important shared factor across experiences of music and poetry, but that other mechanisms distinguish the generation of aesthetic appreciation between these two media.

The speech-to-song (STS) illusion is a phenomenon in which some spoken utterances perceptually transform to song after repetition [Deutsch, Henthorn, and Lapidis (2011). J. Acoust. Soc. Am. 129, 2245-2252]. Tierney, Dick, Deutsch, and Sereno [(2013). Cereb. Cortex. 23, 249-254] developed a set of stimuli where half tend to transform to perceived song with repetition and half do not. Those that transform and those that do not can be understood to induce a musical or linguistic mode of listening, respectively. By comparing performance on perceptual tasks related to transforming and non-transforming utterances, the current study examines whether the musical mode of listening entails higher sensitivity to temporal regularity and better absolute pitch (AP) memory compared to the linguistic mode. In experiment 1, inter-stimulus intervals within STS trials were steady, slightly variable, or highly variable. Participants reported how temporally regular utterance entrances were. In experiment 2, participants performed an AP memory task after a blocked STS exposure phase. Utterances identically matching those used in the exposure phase were targets among transposed distractors in the test phase. Results indicate that listeners exhibit heightened awareness of temporal manipulations but reduced awareness of AP manipulations to transforming utterances. This methodology establishes a framework for implicitly differentiating musical from linguistic perception.

The speech-to-song illusion tracks a perceptual transformation across repetitions where a stimulus that originally sounded like speech comes to sound like song. This article examines whether the illusion also generalizes to other kinds of nonspeech sounds. Participants heard each of 20 environmental sound clips repeated in either original or jumbled form. They rated the musicality of the clips on a 5-point scale where 1 represented sounds exactly like environmental sound and 5 sounds exactly like music. Average ratings increased significantly across repetitions, suggesting that the speech-to-song illusion is one form of a more general sound-to-music illusion produced by repetition. This illusion occurred regardless of whether the clips were repeated in original or jumbled form, marking a difference compared to speech, for which the illusion only occurred if the repetitions were exact.

In research on psychological time, it is important to examine the subjective duration of entire stimulus sequences, such as those produced by music (Teki, Frontiers in Neuroscience, 10, 2016). Yet research on the temporal oddball illusion (according to which oddball stimuli seem longer than standard stimuli of the same duration) has examined only the subjective duration of single events contained within sequences, not the subjective duration of sequences themselves. Does the finding that oddballs seem longer than standards translate to entire sequences, such that entire sequences that contain oddballs seem longer than those that do not? Is this potential translation influenced by the mode of information processing-whether people are engaged in direct or indirect temporal processing? Two experiments aimed to answer both questions using different manipulations of information processing. In both experiments, musical sequences either did or did not contain oddballs (auditory sliding tones). To manipulate information processing, we varied the task (Experiment 1), the sequence event structure (Experiments 1 and 2), and the sequence familiarity (Experiment 2) independently within subjects. Overall, in both experiments, the sequences that contained oddballs seemed shorter than those that did not when people were engaged in direct temporal processing, but longer when people were engaged in indirect temporal processing. These findings support the dual-process contingency model of time estimation (Zakay, Attention, Perception & Psychophysics, 54, 656-664, 1993). Theoretical implications for attention-based and memory-based models of time estimation, the pacemaker accumulator and coding efficiency hypotheses of time perception, and dynamic attending theory are discussed.