Music listening evokes story-like visual imagery with both idiosyncratic and shared content.

There is growing evidence that music can induce a wide range of visual imagery. To date, however, there have been few thorough investigations into the specific content of music-induced visual imagery, and whether listeners exhibit consistency within themselves and with one another regarding their visual imagery content. We recruited an online sample (N = 353) who listened to three orchestral film music excerpts representing happy, tender, and fearful emotions. For each excerpt, listeners rated how much visual imagery they were experiencing and how vivid it was, their liking of and felt emotional intensity in response to the excerpt, and, finally, described the content of any visual imagery they may have been experiencing. Further, they completed items assessing a number of individual differences including musical training and general visual imagery ability. Of the initial sample, 254 respondents completed the survey again three weeks later. A thematic analysis of the content descriptions revealed three higher-order themes of prominent visual imagery experiences: Storytelling (imagined locations, characters, actions, etc.), Associations (emotional experiences, abstract thoughts, and memories), and References (origins of the visual imagery, e.g., film and TV). Although listeners demonstrated relatively low visual imagery consistency with each other, levels were higher when considering visual imagery content within individuals across timepoints. Our findings corroborate past literature regarding music's capacity to encourage narrative engagement. It, however, extends it (a) to show that such engagement is highly visual and contains other types of imagery to a lesser extent, (b) to indicate the idiosyncratic tendencies of listeners' imagery consistency, and (c) to reveal key factors influencing consistency levels (e.g., vividness of visual imagery and emotional intensity ratings in response to music). Further implications are discussed in relation to visual imagery's purported involvement in music-induced emotions and aesthetic appeal.

Intracranial markers of emotional valence processing and judgments in music.

The involvement of the amygdala and orbitofrontal cortex in the processing of valenced stimuli is well established. However, less is known about the extent to which activity in these regions reflects a stimulus' physical properties, the individual subjective experience it evokes, or both. We recorded cortical electrical activity from five epileptic patients implanted with depth electrodes for presurgical evaluation while they rated "consonant" and "dissonant" musical chords using a "pleasantness" scale. We compared the pattern of responses in the amygdala and orbitofrontal cortex when trials were sorted by pleasantness judgments relative to when they were sorted by the acoustic properties known to influence emotional reactions to musical chords. This revealed earlier differential activity in the amygdala in the physical properties-based, relative to in the judgment-based, analyses. Thus, our results demonstrate that the amygdala has, first and foremost, a high initial sensitivity to the physical properties of valenced stimuli. The finding that differentiations in the amygdala based on pleasantness ratings had a longer latency suggests that in this structure, mediation of emotional judgment follows accumulation of sensory information. This is in contrast to the orbitofrontal cortex where sensitivity to sensory information did not precede differentiation based on affective judgments.

An Intracranial EEG Study of the Neural Dynamics of Musical Valence Processing.

The processing of valence is known to recruit the amygdala, orbitofrontal cortex, and relevant sensory areas. However, how these regions interact remains unclear. We recorded cortical electrical activity from 7 epileptic patients implanted with depth electrodes for presurgical evaluation while they listened to positively and negatively valenced musical chords. Time-frequency analysis suggested a specific role of the orbitofrontal cortex in the processing of positively valenced stimuli while, most importantly, Granger causality analysis revealed that the amygdala tends to drive both the orbitofrontal cortex and the auditory cortex in theta and alpha frequency bands, during the processing of valenced stimuli. Results from the current study show the amygdala to be a critical hub in the emotion processing network: specifically one that influences not only the higher order areas involved in the evaluation of a stimulus's emotional value but also the sensory cortical areas involved in the processing of its low-level acoustic features.

Electrophysiological correlates of melodic processing in congenital amusia.

Music listening involves using previously internalized regularities to process incoming musical structures. A condition known as congenital amusia is characterized by musical difficulties, notably in the detection of gross musical violations. However, there has been increasing evidence that individuals with the disorder show preserved musical ability when probed using implicit methods. To further characterize the degree to which amusic individuals show evidence of latent sensitivity to musical structure, particularly in the context of stimuli that are ecologically valid, electrophysiological recordings were taken from a sample of amusic and control participants as they listened to real melodies. To encourage them to pay attention to the music, participants were asked to detect occasional notes in a different timbre. Using a computational model of auditory expectation to identify points of varying levels of expectedness in these melodies (in units of information content (IC), a measure which has an inverse relationship with probability), ERP analysis investigated the extent to which the amusic brain differs from that of controls when processing notes of high IC (low probability) as compared to low IC ones (high probability). The data revealed a novel effect that was highly comparable in both groups: Notes with high IC reliably elicited a delayed P2 component relative to notes with low IC, suggesting that amusic individuals, like controls, found these notes more difficult to evaluate. However, notes with high IC were also characterized by an early frontal negativity in controls that was attenuated in amusic individuals. A correlation of this early negative effect with the ability to make accurate note expectedness judgments (previous data collected from a subset of the current sample) was shown to be present in typical individuals but compromised in individuals with amusia: a finding in line with evidence of a close relationship between the amplitude of such a response and explicit knowledge of musical deviance.

Tracking of pitch probabilities in congenital amusia.

Auditory perception involves not only hearing a series of sounds but also making predictions about future ones. For typical listeners, these predictions are formed on the basis of long-term schematic knowledge, gained over a lifetime of exposure to the auditory environment. Individuals with a developmental disorder known as congenital amusia show marked difficulties with music perception and production. The current study investigated whether these difficulties can be explained, either by a failure to internalise the statistical regularities present in music, or by a failure to consciously access this information. Two versions of a melodic priming paradigm were used to probe participants' abilities to form melodic pitch expectations, in an implicit and an explicit manner. In the implicit version (Experiment 1), participants made speeded, forced-choice discriminations concerning the timbre of a cued target note. In the explicit version (Experiment 2), participants used a 1-7 rating scale to indicate the degree to which the pitch of the cued target note was expected or unexpected. Target notes were chosen to have high or low probability in the context of the melody, based on the predictions of a computational model of melodic expectation. Analysis of the data from the implicit task revealed a melodic priming effect in both amusic and control participants whereby both groups showed faster responses to high probability than low probability notes rendered in the same timbre as the context. However, analysis of the data from the explicit task revealed that amusic participants were significantly worse than controls at using explicit ratings to differentiate between high and low probability events in a melodic context. Taken together, findings from the current study make an important contribution in demonstrating that amusic individuals track melodic pitch probabilities at an implicit level despite an impairment, relative to controls, when required to make explicit judgments in this regard. However the unexpected finding that amusics nevertheless are able to use explicit ratings to distinguish between high and low probability notes (albeit not as well as controls) makes a similarly important contribution in revealing a sensitivity to musical structure that has not previously been demonstrated in these individuals.