Characterization of functional brain connectivity towards optimization of music selection for therapy: a fMRI study

Sleep-aiding music therapy for insomnia: Exploring EEG functional connectivity of sleep-related attentional bias

STUDY OBJECTIVES

This study aimed to investigate the relationship between sleep-aiding music and sleep-related attentional bias based on electroencephalography (EEG) functional connectivity (FC) in patients with insomnia disorder (ID), to evaluate the effectiveness of music in aiding sleep.

METHOD

This study included 30 participants, comprising 15 patients with ID and 15 healthy controls (HCs). Six types of music were selected for sleep aid, and a dot-probe task based on sleep-related attentional bias was utilized to collect behavioral and EEG data. Vigilance bias and disengagement bias were measured using reaction time and EEG FC. Differences in sleep-related attentional bias before and after the intervention of music were explored to evaluate the sleep-aiding effects and identify EEG biomarkers.

RESULTS

Compared with HCs, patients with ID showed decreased sleep-related attentional bias of EEG FC between occipital-central and temporal-frontal lobes. Among the six types of music, International Standard Sleep Aid and Lullaby had a greater impact on decreasing vigilance bias in the ID group. Additionally, the International Standard Sleep Aid and Nature Sound were more effective in decreasing disengagement bias in the ID group. This study also examined the resting-state EEG FC of patients with ID before and after the intervention of music. The results showed that the FC in the temporal, frontal, and occipital lobes significantly differed before and after the intervention of music, especially with the use of International Standard Sleep Aid, Lullaby, and Alpha Sound Wave. However, it is worth noting that these three types of music showed no similarities in EEG FC, in contrast to the result of sleep-related attentional bias of EEG FC.

CONCLUSION

This study found that the sleep-related attentional bias of EEG FC has more distinct characteristics when compared to resting-state EEG FC. The results suggest that the sleep-related attentional bias of EEG FC could be a potential biomarker for assessing the sleep-aiding effect of music interventions. International Standard Sleep Aid was the most effective for patients with ID among six types of sleep-aiding music. These findings could facilitate the development of personalized therapies for patients with ID.

CLINICAL TRIALS REGISTRATION

Chinese Clinical Trial Register, http://www.chictr.org.cn, ID: ChiCTR2400081608.

Emotion brain network topology in healthy subjects following passive listening to different auditory stimuli

A large body of research establishes the efficacy of musical intervention in many aspects of physical, cognitive, communication, social, and emotional rehabilitation. However, the underlying neural mechanisms for musical therapy remain elusive. This study aimed to investigate the potential neural correlates of musical therapy, focusing on the changes in the topology of emotion brain network. To this end, a Bayesian statistical approach and a cross-over experimental design were employed together with two resting-state magnetoencephalography (MEG) as controls. MEG recordings of 30 healthy subjects were acquired while listening to five auditory stimuli in random order. Two resting-state MEG recordings of each subject were obtained, one prior to the first stimulus (pre) and one after the final stimulus (post). Time series at the level of brain regions were estimated using depth-weighted minimum norm estimation (wMNE) source reconstruction method and the functional connectivity between these regions were computed. The resultant connectivity matrices were used to derive two topological network measures: transitivity and global efficiency which are important in gauging the functional segregation and integration of brain network respectively. The differences in these measures between pre- and post-stimuli resting MEG were set as the equivalence regions. We found that the network measures under all auditory stimuli were equivalent to the resting state network measures in all frequency bands, indicating that the topology of the functional brain network associated with emotional regulation in healthy subjects remains unchanged following these auditory stimuli. This suggests that changes in the emotion network topology may not be the underlying neural mechanism of musical therapy. Nonetheless, further studies are required to explore the neural mechanisms of musical interventions especially in the populations with neuropsychiatric disorders.

Effect of Music Therapy on Negative Psychology, Sleep, and Quality of Life in Elderly Patients Recovering from Cerebral Infarction with Depression and Anxiety: A Retrospective Analysis

OBJECTIVE

To observe the effects of music therapy on negative psychology, sleep, and quality of life in elderly patients recovering from cerebral infarction accompanied by depression and anxiety.

METHODS

We performed a retrospective analysis of 160 patients with convalescent cerebral infarction diagnosed between December 2022 and December 2023 in the Affiliated Brain Hospital of Nanjing Medical University. Cases from the control group (n = 76) were treated with conventional rehabilitation training. Meanwhile, the music therapy group (n = 84) cases were managed with standard and music therapy. Various measures, including polysomnography, the general quality of life questionnaire-74 (GQOL-74), the self-rating anxiety scale (SAS), and the self-rating depression scale (SDS) were collected at baseline (admission) and 4 weeks post-admission.

RESULTS

After 4 weeks, the music therapy group exhibited higher GQOL-74 scores, lower SAS scores, and lower SDS scores (P < 0.001). Furthermore, compared with the control group, the music therapy group had shorter sleep latency, longer sleep duration, higher sleep efficiency, lower wake time, fewer wake times, shorter S1 stage, longer S3 + S4 stage, and longer REM period (P < 0.001).

CONCLUSIONS

Music therapy appears to be effective in improving negative psychology, sleep quality, and quality of life in elderly patients with comorbid depression and anxiety during recovery from cerebral infarction.

Beyond the ears: A review exploring the interconnected brain behind the hierarchical memory of music

Music is a ubiquitous element of daily life. Understanding how music memory is represented and expressed in the brain is key to understanding how music can influence human daily cognitive tasks. Current music-memory literature is built on data from very heterogeneous tasks for measuring memory, and the neural correlates appear to differ depending on different forms of memory function targeted. Such heterogeneity leaves many exceptions and conflicts in the data underexplained (e.g., hippocampal involvement in music memory is debated). This review provides an overview of existing neuroimaging results from music-memory related studies and concludes that although music is a special class of event in our lives, the memory systems behind it do in fact share neural mechanisms with memories from other modalities. We suggest that dividing music memory into different levels of a hierarchy (structural level and semantic level) helps understand overlap and divergence in neural networks involved. This is grounded in the fact that memorizing a piece of music recruits brain clusters that separately support functions including-but not limited to-syntax storage and retrieval, temporal processing, prediction versus reality comparison, stimulus feature integration, personal memory associations, and emotion perception. The cross-talk between frontal-parietal music structural processing centers and the subcortical emotion and context encoding areas explains why music is not only so easily memorable but can also serve as strong contextual information for encoding and retrieving nonmusic information in our lives.

Current scenario and potential of music therapy in the management of diseases

Over the preceding years, music therapy has gained tremendous attention due to new findings of music in management of various conditions like Alzheimer's, depression, anxiety, insomnia, etc. Music is a non-invasive, patient-friendly and pleasant form of therapy with minimal or no side effects. It activates the reward pathway of brain by influencing several processes such as dopamine release, reduction in cortisol levels, increase in estrogen and testosterone levels. This review article focuses on advantages and disadvantages of music therapy, mechanism of action of music in brain and its effective applications in the management of different diseases. The article covers history of music therapy in America, Egypt, and India with practice of music therapy. The advanced effects of music therapy in autism, cancer, post-operative pain, Parkinson's disease, selective mutism, stroke, heart problems, pregnancy, eating disorders, bone fractures and obsessive compulsive disorders are discussed. Also the effect of music therapy on the quality of sleep and brain waves has been discussed. This is an established profession in western countries like America, UK, Australia, and Canada, but not in low-income countries like India where it needs to be standardized.

Quality standards and recommendations for research in music and neuroplasticity

Research on how music influences brain plasticity has gained momentum in recent years. Considering, however, the nonuniform methodological standards implemented, the findings end up being nonreplicable and less generalizable. To address the need for a standardized baseline of research quality, we gathered all the studies in the music and neuroplasticity field in 2019 and appraised their methodological rigor systematically and critically. The aim was to provide a preliminary and, at the minimum, acceptable quality threshold-and, ipso facto, suggested recommendations-whereupon further discussion and development may take place. Quality appraisal was performed on 89 articles by three independent raters, following a standardized scoring system. The raters' scoring was cross-referenced following an inter-rater reliability measure, and further studied by performing multiple ratings comparisons and matrix analyses. The results for methodological quality were at a quite good level (quantitative articles: mean = 0.737, SD = 0.084; qualitative articles: mean = 0.677, SD = 0.144), following a moderate but statistically significant level of agreement between the raters (W = 0.44, χ² = 117.249, p = 0.020). We conclude that the standards for implementation and reporting are of high quality; however, certain improvements are needed to reach the stringent levels presumed for such an influential interdisciplinary scientific field.

Reading music and words: The anatomical connectivity of musicians' visual cortex

Musical score reading and word reading have much in common, from their historical origins to their cognitive foundations and neural correlates. In the ventral occipitotemporal cortex (VOT), the specialization of the so-called Visual Word Form Area for word reading has been linked to its privileged structural connectivity to distant language regions. Here we investigated how anatomical connectivity relates to the segregation of regions specialized for musical notation or words in the VOT. In a cohort of professional musicians and non-musicians, we used probabilistic tractography combined with task-related functional MRI to identify the connections of individually defined word- and music-selective left VOT regions. Despite their close proximity, these regions differed significantly in their structural connectivity, irrespective of musical expertise. The music-selective region was significantly more connected to posterior lateral temporal regions than the word-selective region, which, conversely, was significantly more connected to anterior ventral temporal cortex. Furthermore, musical expertise had a double impact on the connectivity of the music region. First, music tracts were significantly larger in musicians than in non-musicians, associated with marginally higher connectivity to perisylvian music-related areas. Second, the spatial similarity between music and word tracts was significantly increased in musicians, consistently with the increased overlap of language and music functional activations in musicians, as compared to non-musicians. These results support the view that, for music as for words, very specific anatomical connections influence the specialization of distinct VOT areas, and that reciprocally those connections are selectively enhanced by the expertise for word or music reading.

Cortical network underlying audiovisual semantic integration and modulation of attention: An fMRI and graph-based study

Many neuroimaging and electrophysiology studies have suggested that semantic integration as a high-level cognitive process involves various cortical regions and is modulated by attention. However, the cortical network specific to semantic integration and the modulatory mechanism of attention remain unclear. Here, we designed an fMRI experiment using “bimodal stimulus” to extract information regarding the cortical activation related to the effects of semantic integration with and without attention, and then analyzed the characteristics of the cortical network and the modulating effect of attention on semantic integration. To further investigate the related cortical regions, we constructed a functional brain network for processing attended AV stimuli to evaluate the nodal properties using a graph-based method. The results of the fMRI and graph-based analyses showed that the semantic integration with attention activated the anterior temporal lobe (ATL), temporoparietal junction (TPJ), and frontoparietal cortex, with the ATL showing the highest nodal degree and efficiency; in contrast, semantic integration without attention involved a relatively small cortical network, including the posterior superior temporal gyrus (STG), Heschl’s gyrus (HG), and precentral gyrus. These results indicated that semantic integration is a complex cognitive process that occurs not only in the attended condition but also in the unattended condition, and that attention could modulate the distribution of cortical networks related to semantic integration. We suggest that semantic integration with attention is a conscious process and needs a wide cortical network working together, in which the ATL plays the role of a central hub; in contrast, semantic integration without attention is a pre-attentive process and involves a relatively smaller cortical network, in which the HG may play an important role. Our study will provide valuable insights into semantic integration and will be useful for investigations on multisensory integration and attention mechanism at multiple processing stages and levels within the cortical hierarchy.