Tunes stuck in your brain: The frequency and affective evaluation of involuntary musical imagery correlate with cortical structure

Transcranial magnetic stimulation as a novel approach to effectively treat musical obsession (stuck song syndrome): a case series and a systematic review of case reports

This is the first case series that demonstrates the use of transcranial magnetic stimulation (TMS) for the treatment of musical obsessions or stuck song syndrome (SSS), following a systematic review that identified existing treatments. SSS can occur independently, but in literature it is commonly reported as an obsessive-compulsive disorder (OCD) or major depressive disorder (MDD) symptom. Most people are familiar with earworms, experienced by up to 98% of the western population. Earworms can become severe leading to the SSS diagnosis. SSS is a distressing repetition of involuntary tunes persisting in one's mind. According to literature, SSS has often been treated using antidepressants which are used to treat MDD and OCD. As TMS has shown a positive therapeutic effect for psychiatric disorders particularly MDD and OCD, we hypothesized that TMS could be an effective treatment that reduces symptoms of patients with SSS. We present two cases of TMS treatment contributing to a reduction in symptoms of SSS. We also aim to provide a systematic review of cases where SSS has been described and compare the pharmacological or psychotherapeutic treatments used with our novel TMS interventions for SSS. This report highlights some limitations, including patient's psychiatric comorbidities and treatment protocol changes, which affect the findings generalizability. Despite these limitations, TMS appears promising as a treatment for SSS due to the observed effectiveness in reducing SSS symptoms and minimal side effects especially in medication-resistant cases.

Validation of the Persian Involuntary Musical Imagery Scale alongside multifaceted investigation of earworms among Iranian college students

Introduction

Involuntary musical imagery is considered a ubiquitous phenomenon worldwide, while mixed and inconsistent results regarding different aspects of earworms remain challenging. Furthermore, there is a special need for research on earworms in societies other than in European or American. The primary aim of our study is to validate the Persian Involuntary Musical Imagery Scale (PIMIS) and, secondly, to carry out a detailed exploration of earworms among Iranian college students.

Methods

A total of 946 Iranian college students were recruited to answer the Persian Involuntary Musical Imagery Scale (PIMIS), and gold standards including the Thought Control Questionnaire (TCQ, to convergent validity), the Depression, Anxiety, and Stress Scale (DASS-21, to concurrent validity), the White Bear Suppression Inventory (WBSI, to predictive validity), as well as the NEO Five-Factor Inventory (NEO-FFI), the Obsessive-Compulsive Inventory-revised (OCI-R), and socio-demographic queries. A complex of features regarding the validity and reliability of the PIMIS, along with numerous aspects of earworm, were explored.

Results and discussion

The Persian Involuntary Musical Imagery Scale encompasses 15 items along with three additional questions. It was found to be a valid and reliable instrument among Iranian college students, qualified to measure individual differences in earworms. Phenomenological evidence and detailed data on individual differences could provide rich knowledge for the rest of the literature paradigms. Moreover, future investigations into the local regions of the Iranian population are recommended.

Learning to play a musical instrument in the middle school is associated with superior audiovisual working memory and fluid intelligence: A cross-sectional behavioral study

Music training, in all its forms, is known to have an impact on behavior both in childhood and even in aging. In the delicate life period of transition from childhood to adulthood, music training might have a special role for behavioral and cognitive maturation. Among the several kinds of music training programs implemented in the educational communities, we focused on instrumental training incorporated in the public middle school curriculum in Italy that includes both individual, group and collective (orchestral) lessons several times a week. At three middle schools, we tested 285 preadolescent children (aged 10–14 years) with a test and questionnaire battery including adaptive tests for visuo-spatial working memory skills (with the Jack and Jill test), fluid intelligence (with a matrix reasoning test) and music-related perceptual and memory abilities (with listening tests). Of these children, 163 belonged to a music curriculum within the school and 122 to a standard curriculum. Significant differences between students of the music and standard curricula were found in both perceptual and cognitive domains, even when controlling for pre-existing individual differences in musical sophistication. The music children attending the third and last grade of middle school had better performance and showed the largest advantage compared to the control group on both audiovisual working memory and fluid intelligence. Furthermore, some gender differences were found for several tests and across groups in favor of females. The present results indicate that learning to play a musical instrument as part of the middle school curriculum represents a resource for preadolescent education. Even though the current evidence is not sufficient to establish the causality of the found effects, it can still guide future research evaluation with longitudinal data.

Musical Hallucinations in Chronic Pain: The Anterior Cingulate Cortex Regulates Internally Generated Percepts

The anterior cingulate cortex (ACC) has been extensively implicated in the functional brain network underlying chronic pain. Electrical stimulation of the ACC has been proposed as a therapy for refractory chronic pain, although, mechanisms of therapeutic action are still unclear. As stimulation of the ACC has been reported to produce many different behavioral and perceptual responses, this region likely plays a varied role in sensory and emotional integration as well as modulating internally generated perceptual states. In this case series, we report the emergence of subjective musical hallucinations (MH) after electrical stimulation of the ACC in two patients with refractory chronic pain. In an N-of-1 analysis from one patient, we identified neural activity (local field potentials) that distinguish MH from both the non-MH condition and during a task involving music listening. Music hallucinations were associated with reduced alpha band activity and increased gamma band activity in the ACC. Listening to similar music was associated with different changes in ACC alpha and gamma power, extending prior results that internally generated perceptual phenomena are supported by circuits in the ACC. We discuss these findings in the context of phantom perceptual phenomena and posit a framework whereby chronic pain may be interpreted as a persistent internally generated percept.

Involuntary musical imagery as a component of ordinary music cognition: A review of empirical evidence

Involuntary musical imagery (INMI) refers to a conscious mental experience of music that occurs without deliberate efforts to initiate or sustain it. This experience often consists of the repetition of a short fragment of a melody, colloquially called an "earworm." Here, we present the first comprehensive, qualitative review of published empirical research on INMI to date. We performed an extensive literature search and discovered, in total, 47 studies from 33 peer-reviewed articles that met the inclusion criteria for the review. In analyzing the content of these studies, we identified four major research themes, which concern the phenomenology, dynamics, individual differences, and musical features of INMI. The findings answer many questions of scientific interest-for instance, what is typical in terms of INMI frequency, duration, and content; which factors influence INMI onset; and whether demographic and personality factors can explain individual differences in susceptibility and responses to INMI. This review showcases INMI as a well-established phenomenon in light of a substantial body of empirical studies that have accumulated consistent results. Although the populations under study show an unfavorable bias towards Western, educated participants, the evidence depicts INMI as a universal psychological phenomenon, the possible function of which we do not yet fully understand. The concluding section introduces several suggestions for future research to expand on the topic.

Mental Effort When Playing, Listening, and Imagining Music in One Pianist's Eyes and Brain

We investigated "musical effort" with an internationally renowned, classical, pianist while playing, listening, and imagining music. We used pupillometry as an objective measure of mental effort and fMRI as an exploratory method of effort with the same musical pieces. We also compared a group of non-professional pianists and non-musicians by the use of pupillometry and a small group of non-musicians with fMRI. This combined approach of psychophysiology and neuroimaging revealed the cognitive work during different musical activities. We found that pupil diameters were largest when "playing" (regardless of whether there was sound produced or not) compared to conditions with no movement (i.e., "listening" and "imagery"). We found positive correlations between pupil diameters of the professional pianist during different conditions with the same piano piece (i.e., normal playing, silenced playing, listen, imagining), which might indicate similar degrees of load on cognitive resources as well as an intimate link between the motor imagery of sound-producing body motions and gestures. We also confirmed that musical imagery had a strong commonality with music listening in both pianists and musically naïve individuals. Neuroimaging provided evidence for a relationship between noradrenergic (NE) activity and mental workload or attentional intensity within the domain of music cognition. We found effort related activity in the superior part of the locus coeruleus (LC) and, similarly to the pupil, the listening and imagery engaged less the LC-NE network than the motor condition. The pianists attended more intensively to the most difficult piece than the non-musicians since they showed larger pupils for the most difficult piece. Non-musicians were the most engaged by the music listening task, suggesting that the amount of attention allocated for the same task may follow a hierarchy of expertise demanding less attentional effort in expert or performers than in novices. In the professional pianist, we found only weak evidence for a commonality between subjective effort (as rated measure-by-measure) and the objective effort gauged with pupil diameter during listening. We suggest that psychophysiological methods like pupillometry can index mental effort in a manner that is not available to subjective awareness or introspection.

Individual traits that influence the frequency and emotional characteristics of involuntary musical imagery: An experience sampling study

In this study, we investigated individual traits that influence the frequency of involuntary musical imagery (INMI) and the emotional valence of these occurrences using the experience sampling method (ESM) that measures INMI in daily life at the moment they occur. As individual traits, the effects of non-clinical obsessive-compulsive (OC) tendencies, personality traits, and musical expertise were examined. Among them, we were particularly interested in the effect of OC tendencies that are assumed to be related to INMI but are yet to be fully examined using ESM. A total of 101 university students completed questionnaires that assessed OC tendencies, the Big Five personality traits, and musical expertise. During the seven-day sampling period, participants received smartphone notifications six times per day and responded by stating whether they had experienced INMI and described the emotional characteristics of those occurrences. A multilevel analysis showed the relationship between OC tendencies and INMI. A positive effect was observed for intrusive thoughts (obsession) on the occurrence of INMI. Regarding the emotional characteristics of INMI, a negative effect of compulsive washing was observed on both the pleasantness of INMI experiences and the extent to which the participants liked the music they had heard internally. The effects of both personality traits and musical expertise were also observed in the analysis of INMI occurrences, both of which are consistent with previous findings. In summary, the present study using ESM supports previous findings on individual traits that affect INMI and clarifies them with additional detail and accuracy.

Musical imagery depends upon coordination of auditory and sensorimotor brain activity

Recent magnetoencephalography (MEG) studies have established that sensorimotor brain rhythms are strongly modulated during mental imagery of musical beat and rhythm, suggesting that motor regions of the brain are important for temporal aspects of musical imagery. The present study examined whether these rhythms also play a role in non-temporal aspects of musical imagery including musical pitch. Brain function was measured with MEG from 19 healthy adults while they performed a validated musical pitch imagery task and two non-imagery control tasks with identical temporal characteristics. A 4-dipole source model probed activity in bilateral auditory and sensorimotor cortices. Significantly greater β-band modulation was found during imagery compared to control tasks of auditory perception and mental arithmetic. Imagery-induced β-modulation showed no significant differences between auditory and sensorimotor regions, which may reflect a tightly coordinated mode of communication between these areas. Directed connectivity analysis in the θ-band revealed that the left sensorimotor region drove left auditory region during imagery onset. These results add to the growing evidence that motor regions of the brain are involved in the top-down generation of musical imagery, and that imagery-like processes may be involved in musical perception.

Musical hallucinations, musical imagery, and earworms: A new phenomenological survey

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We conducted a phenomenological survey comparing musical hallucinations to other inner music.

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MH were more likely to be reported as externally located than other experiences.

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MH were less controllable and less familiar than imagery or earworms.

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MH were less likely to include lyrical content than other forms of inner music.

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Individuals with higher levels of musical expertise were less likely to report MH.

Musical hallucinations (MH) account for a significant proportion of auditory hallucinations, but there is a relative lack of research into their phenomenology. In contrast, much research has focused on other forms of internally generated musical experience, such as earworms (involuntary and repetitive inner music), showing that they can vary in perceived control, repetitiveness, and in their effect on mood. We conducted a large online survey (N = 270), including 44 participants with MH, asking participants to rate imagery, earworms, or MH on several variables. MH were reported as occurring less frequently, with less controllability, less lyrical content, and lower familiarity, than other forms of inner music. MH were also less likely to be reported by participants with higher levels of musical expertise. The findings are outlined in relation to other forms of hallucinatory experience and inner music, and their implications for psychological models of hallucinations discussed.

"Radio Inside My Head": A Curious Case of Early Onset "Stuck Song Syndrome" or Obsessive-Compulsive Disorder with Predominant Musical Obsession

Musical obsessions also called "stuck song syndrome" is a topic of limited research. It is among the most poorly understood and rare phenomenology. There are only a few cases reported across the world which describes it. Subjects usually present with complaints of continuous play of a musical tune in the head which the subject is unable to remove. Because of its similarity in presentation with auditory musical hallucination, it presents a diagnostic dilemma to the clinician. Here, we present the case of a 25-year-old man who presented with this particular phenomenon, and the approach we took to manage it.

Roles of Supplementary Motor Areas in Auditory Processing and Auditory Imagery

Although the supplementary and pre-supplementary motor areas have been intensely investigated in relation to their motor functions, they are also consistently reported in studies of auditory processing and auditory imagery. This involvement is commonly overlooked, in contrast to lateral premotor and inferior prefrontal areas. We argue here for the engagement of supplementary motor areas across a variety of sound categories, including speech, vocalizations, and music, and we discuss how our understanding of auditory processes in these regions relate to findings and hypotheses from the motor literature. We suggest that supplementary and pre-supplementary motor areas play a role in facilitating spontaneous motor responses to sound, and in supporting a flexible engagement of sensorimotor processes to enable imagery and to guide auditory perception.

Hearing and imagining sounds–including speech, vocalizations, and music–can recruit SMA and pre-SMA, which are normally discussed in relation to their motor functions.

Emerging research indicates that individual differences in the structure and function of SMA and pre-SMA can predict performance in auditory perception and auditory imagery tasks.

Responses during auditory processing primarily peak in pre-SMA and in the boundary area between pre-SMA and SMA. This boundary area is crucially involved in the control of speech and vocal production, suggesting that sounds engage this region in an effector-specific manner.

Activating sound-related motor representations in SMA and pre-SMA might facilitate behavioral responses to sounds. This might also support a flexible generation of sensory predictions based on previous experience to enable imagery and guide perception.

Don't forget the lyrics! Spatiotemporal dynamics of neural mechanisms spontaneously evoked by gaps of silence in familiar and newly learned songs

The vast majority of people experience musical imagery, the sensation of reliving a song in absence of any external stimulation. Internal perception of a song can be deliberate and effortful, but also may occur involuntarily and spontaneously. Moreover, musical imagery is also involuntarily used for automatically completing missing parts of music or lyrics from a familiar song. The aim of our study was to explore the onset of musical imagery dynamics that leads to the automatic completion of missing lyrics. High-density electroencephalography was used to record the cerebral activity of twenty healthy volunteers while they were passively listening to unfamiliar songs, very familiar songs, and songs previously listened to for two weeks. Silent gaps inserted into these songs elicited a series of neural activations encompassing perceptual, attentional and cognitive mechanisms (range 100-500ms). Familiarity and learning effects emerged as early as 100ms and lasted 400ms after silence occurred. Although participants reported more easily mentally imagining lyrics in familiar rather than passively learnt songs, the onset of neural mechanisms and the power spectrum underlying musical imagery were similar for both types of songs. This study offers new insights into the musical imagery dynamics evoked by gaps of silence and on the role of familiarity and learning processes in the generation of these dynamics. The automatic and effortless method presented here is a potentially useful tool to understand failure in the familiarity and learning processes of pathological populations.