Adults and children processing music: An fMRI study

From singing to speaking: facilitating recovery from nonfluent aphasia

It has been reported for more than 100 years that patients with severe nonfluent aphasia are better at singing lyrics than they are at speaking the same words. This observation led to the development of melodic intonation therapy (MIT). However, the efficacy of this therapy has yet to be substantiated in a randomized controlled trial. Furthermore, its underlying neural mechanisms remain unclear. The two unique components of MIT are the intonation of words and simple phrases using a melodic contour that follows the prosody of speech and the rhythmic tapping of the left hand that accompanies the production of each syllable and serves as a catalyst for fluency. Research has shown that both components are capable of engaging fronto-temporal regions in the right hemisphere, thereby making MIT particularly well suited for patients with large left hemisphere lesions who also suffer from nonfluent aphasia. Recovery from aphasia can happen in two ways: either through the recruitment of perilesional brain regions in the affected hemisphere, with variable recruitment of right-hemispheric regions if the lesion is small, or through the recruitment of homologous language and speech-motor regions in the unaffected hemisphere if the lesion of the affected hemisphere is extensive. Treatment-associated neural changes in patients undergoing MIT indicate that the unique engagement of right-hemispheric structures (e.g., the superior temporal lobe, primary sensorimotor, premotor and inferior frontal gyrus regions) and changes in the connections across these brain regions may be responsible for its therapeutic effect.

Event-related potential (ERP) markers of melodic processing: The N2 component is modulated by structural complexity, not by melodic 'meaningfulness'

Previous studies have demonstrated that the event-related potential (ERP) evoked by a note shows substantial differences depending on whether the note is part of a melodic context or presented in an unstructured repetition. In particular, the N2 component has been found to have considerably increased latency and a more frontal topography for notes presented in a melody. An open question is whether such effect is related to the 'meaningfulness' of a note sequence, that is due to the formation of abstract melodic entities, rather than more simply an indicator of cognitive load associated with processing a structurally-complex sequence as opposed to an unstructured repetition. In this study, we addressed this issue by recording ERPs from 10 healthy non-musicians listening to eight one-part unfamiliar tonal melodies and eight sequences of random notes. The two stimuli were matched for distribution of pitch, intervals and note duration as well as for entropy of the time-series of pitch and duration. While tonal melodies were rated more meaningful (p<0.001) and pleasant (p<0.001) by all participants, no effects were found for the N2 component amplitude (p> or =0.8) and latency (p=0.2). Combined with previous findings, this indicates that the N2 evoked by each individual note responds to the structural complexity of the note sequence, i.e., to the presence of pitch and duration changes, but not to higher-level processing related to the formation of abstract melodic entities. In contrast, we found that the amplitude of the P2 component was marginally (p=0.04) elevated for random notes as compared to tonal melodies. This may be related to attentional modulation, or more specifically to associative components of auditory processing.

Music and mirror neurons: from motion to 'e'motion

The ability to create and enjoy music is a universal human trait and plays an important role in the daily life of most cultures. Music has a unique ability to trigger memories, awaken emotions and to intensify our social experiences. We do not need to be trained in music performance or appreciation to be able to reap its benefits-already as infants, we relate to it spontaneously and effortlessly. There has been a recent surge in neuroimaging investigations of the neural basis of musical experience, but the way in which the abstract shapes and patterns of musical sound can have such profound meaning to us remains elusive. Here we review recent neuroimaging evidence and suggest that music, like language, involves an intimate coupling between the perception and production of hierarchically organized sequential information, the structure of which has the ability to communicate meaning and emotion. We propose that these aspects of musical experience may be mediated by the human mirror neuron system.

Are left fronto-temporal brain areas a prerequisite for normal music-syntactic processing?

An increasing number of neuroimaging studies in music cognition research suggest that "language areas" are involved in the processing of musical syntax, but none of these studies clarified whether these areas are a prerequisite for normal syntax processing in music. The present electrophysiological experiment tested whether patients with lesions in Broca's area (N=6) or in the left anterior temporal lobe (N=7) exhibit deficits in the processing of structure in music compared to matched healthy controls (N=13). A chord sequence paradigm was applied, and the amplitude and scalp topography of the Early Right Anterior Negativity (ERAN) was examined, an electrophysiological marker of musical syntax processing that correlates with activity in Broca's area and its right hemisphere homotope. Left inferior frontal gyrus (IFG) (but not anterior superior temporal gyrus - aSTG) patients with lesions older than 4 years showed an ERAN with abnormal scalp distribution, and subtle behavioural deficits in detecting music-syntactic irregularities. In one IFG patient tested 7 months post-stroke, the ERAN was extinguished and the behavioural performance remained at chance level. These combined results suggest that the left IFG, known to be crucial for syntax processing in language, plays also a functional role in the processing of musical syntax. Hence, the present findings are consistent with the notion that Broca's area supports the processing of syntax in a rather domain-general way.

Differential effects on pain intensity and unpleasantness of two meditation practices

Pain is an unpleasant sensory and emotional experience that can be regulated by many different cognitive mechanisms. We compared the regulatory qualities of two different meditation practices during noxious thermal stimuli: Focused Attention, directed at a fixation cross away from the stimulation, which could regulate negative affect through a sensory gating mechanism; and Open Monitoring, which could regulate negative affect through a mechanism of nonjudgmental, nonreactive awareness of sensory experience. Here, we report behavioral data from a comparison between novice and long-term meditation practitioners (long-term meditators, LTMs) using these techniques. LTMs, compared to novices, had a significant reduction of self-reported unpleasantness, but not intensity, of painful stimuli while practicing Open Monitoring. No significant effects were found for FA. This finding illuminates the possible regulatory mechanism of meditation-based clinical interventions like Mindfulness-Based Stress Reduction (MBSR). Implications are discussed in the broader context of training-induced changes in trait emotion regulation.

Functional specializations for music processing in the human newborn brain

In adults, specific neural systems with right-hemispheric weighting are necessary to process pitch, melody, and harmony as well as structure and meaning emerging from musical sequences. It is not known to what extent the specialization of these systems results from long-term exposure to music or from neurobiological constraints. One way to address this question is to examine how these systems function at birth, when auditory experience is minimal. We used functional MRI to measure brain activity in 1- to 3-day-old newborns while they heard excerpts of Western tonal music and altered versions of the same excerpts. Altered versions either included changes of the tonal key or were permanently dissonant. Music evoked predominantly right-hemispheric activations in primary and higher order auditory cortex. During presentation of the altered excerpts, hemodynamic responses were significantly reduced in the right auditory cortex, and activations emerged in the left inferior frontal cortex and limbic structures. These results demonstrate that the infant brain shows a hemispheric specialization in processing music as early as the first postnatal hours. Results also indicate that the neural architecture underlying music processing in newborns is sensitive to changes in tonal key as well as to differences in consonance and dissonance.

Contributions to singing ability by the posterior portion of the superior temporal gyrus of the non-language-dominant hemisphere: first evidence from subdural cortical stimulation, Wada testing, and fMRI

INTRODUCTION

Although the substrates that mediate singing abilities in the human brain are not well understood, invasive brain mapping techniques used for clinical decision making such as intracranial electro-cortical testing and Wada testing offer a rare opportunity to examine music-related function in a select group of subjects, affording exceptional spatial and temporal specificity.

METHODS

We studied eight patients with medically refractory epilepsy undergoing indwelling subdural electrode seizure focus localization. All patients underwent Wada testing for language lateralization. Functional assessment of language and music tasks was done by electrode grid cortical stimulation. One patient was also tested non-invasively with functional magnetic resonance imaging (fMRI). Functional organization of singing ability compared to language ability was determined based on four regions-of-interest (ROIs): left and right inferior frontal gyrus (IFG), and left and right posterior superior temporal gyrus (pSTG).

RESULTS

In some subjects, electrical stimulation of dominant pSTG can interfere with speech and not singing, whereas stimulation of non-dominant pSTG area can interfere with singing and not speech. Stimulation of the dominant IFG tends to interfere with both musical and language expression, while non-dominant IFG stimulation was often observed to cause no interference with either task; and finally, that stimulation of areas adjacent to but not within non-dominant pSTG typically does not affect either ability. Functional fMRI mappings of one subject revealed similar music/language dissociation with respect to activation asymmetry within the ROIs.

CONCLUSION

Despite inherent limitations with respect to strictly research objectives, invasive clinical techniques offer a rare opportunity to probe musical and language cognitive processes of the brain in a select group of patients.

Acupuncture combined with music therapy for treatment of 30 cases of cerebral palsy

OBJECTIVE

To observe clinical therapeutic effects of acupuncture combined with music therapy for treatment of cerebral palsy.

METHODS

Sixty children with cerebral palsy were randomly divided into an acupuncture group (Group Acup.) and an acupuncture plus music group (Group Acup.+ M). Simple acupuncture was applied in Group Acup., and acupuncture at 5 groups of points plus music were applied in Group Acup. +M. The treatment was given once every two days with 3 treatments weekly, and 36 treatments constituted a therapeutic course. Therapeutic effects including movement improvement were observed for comparison after 3 courses of treatments.

RESULTS

The comprehensive functions were elevated in both groups, and the total effective rate in Group Acup. + M was obviously better than that in Group Acup (P < 0.05). Movement functions were also improved in both groups, but the differences in improvement of creeping and kneeling, standing, and walking were significant between the two groups (P < 0.01), showing the effect in Group Acup. + M was better than that in Group Acup..

CONCLUSION

The therapy of acupuncture plus music gained better therapeutic effect on cerebral palsy than simple acupuncture, which provided new thoughts for treating the disease by comprehensive therapies.

Time scales of auditory habituation in the amygdala and cerebral cortex

Habituation is a fundamental form of learning manifested by a decrement of neuronal responses to repeated sensory stimulation. In addition, habituation is also known to occur on the behavioral level, manifested by reduced emotional reactions to repeatedly presented affective stimuli. It is, however, not clear which brain areas show a decline in activity during repeated sensory stimulation on the same time scale as reduced valence and arousal experience and whether these areas can be delineated from other brain areas with habituation effects on faster or slower time scales. These questions were addressed using functional magnetic resonance imaging acquired during repeated stimulation with piano melodies. The magnitude of functional responses in the laterobasal amygdala and in related cortical areas and that of valence and arousal ratings, given after each music presentation, declined in parallel over the experiment. In contrast to this long-term habituation (43 min), short-term decreases occurring within seconds were found in the primary auditory cortex. Sustained responses that remained throughout the whole investigated time period were detected in the ventrolateral prefrontal cortex extending to the dorsal part of the anterior insular cortex. These findings identify an amygdalocortical network that forms the potential basis of affective habituation in humans.

Neural correlates of pre-attentive processing of pattern deviance in professional musicians

Pre-attentive registration of aberrations in predictable sound patterns is attributed to the temporal cortex. However, electrophysiology suggests that frontal areas become more important when deviance complexity increases. To play an instrument in an ensemble, professional musicians have to rely on the ability to detect even slight deviances from expected musical patterns and therefore have highly trained aural skills. Here, we aimed to identify the neural correlates of experience-driven plasticity related to the processing of complex sound features. We used functional magnetic resonance imaging in combination with an event-related oddball paradigm and compared brain activity in professional musicians and non-musicians during pre-attentive processing of melodic contour variations. The melodic pattern consisted of a sequence of five tones each lasting 50 ms interrupted by silent interstimulus intervals of 50 ms. Compared to non-musicians, the professional musicians showed enhanced activity in the left middle and superior temporal gyri, the left inferior frontal gyrus and in the right ventromedial prefrontal cortex in response to pattern deviation. This differential brain activity pattern was correlated with behaviorally tested musical aptitude. Our results thus support an experience-related role of the left temporal cortex in fast melodic contour processing and suggest involvement of the prefrontal cortex.

Neural mechanisms of the influence of popularity on adolescent ratings of music

It is well-known that social influences affect consumption decisions. We used functional magnetic resonance imaging (fMRI) to elucidate the neural mechanisms associated with social influence with regard to a common consumer good: music. Our study population was adolescents, age 12-17. Music is a common purchase in this age group, and it is widely believed that adolescent behavior is influenced by perceptions of popularity in their reference group. Using 15-s clips of songs from MySpace.com, we obtained behavioral measures of preferences and neurobiological responses to the songs. The data were gathered with, and without, the overall popularity of the song revealed. Song popularity had a significant effect on the participants' likability ratings of the songs. fMRI results showed a strong correlation between the participants' rating and activity in the caudate nucleus, a region previously implicated in reward-driven actions. The tendency to change one's evaluation of a song was positively correlated with activation in the anterior insula and anterior cingulate, two regions that are associated with physiological arousal and negative affective states. Sensitivity to popularity was linked to lower activation levels in the middle temporal gyrus, suggesting a lower depth of musical semantic processing. Our results suggest that a principal mechanism whereby popularity ratings affect consumer choice is through the anxiety generated by the mismatch between one's own preferences and others'. This mismatch anxiety motivates people to switch their choices in the direction of the consensus. Our data suggest that this is a major force behind the conformity observed in music tastes in some teenagers.

A neuroscientific perspective on music therapy

During the last years, a number of studies demonstrated that music listening (and even more so music production) activates a multitude of brain structures involved in cognitive, sensorimotor, and emotional processing. For example, music engages sensory processes, attention, memory-related processes, perception-action mediation ("mirror neuron system" activity), multisensory integration, activity changes in core areas of emotional processing, processing of musical syntax and musical meaning, and social cognition. It is likely that the engagement of these processes by music can have beneficial effects on the psychological and physiological health of individuals, although the mechanisms underlying such effects are currently not well understood. This article gives a brief overview of factors contributing to the effects of music-therapeutic work. Then, neuroscientific studies using music to investigate emotion, perception-action mediation ("mirror function"), and social cognition are reviewed, including illustrations of the relevance of these domains for music therapy.

Evidence for plasticity in white-matter tracts of patients with chronic Broca's aphasia undergoing intense intonation-based speech therapy

Recovery from aphasia can be achieved through recruitment of either perilesional brain regions in the affected hemisphere or homologous language regions in the nonlesional hemisphere. For patients with large left-hemisphere lesions, recovery through the right hemisphere may be the only possible path. The right-hemisphere regions most likely to play a role in this recovery process are the superior temporal lobe (important for auditory feedback control), premotor regions/posterior inferior frontal gyrus (important for planning and sequencing of motor actions and for auditory-motor mapping), and the primary motor cortex (important for execution of vocal motor actions). These regions are connected reciprocally via a major fiber tract called the arcuate fasciculus (AF), however, this tract is not as well developed in the right hemisphere as it is in the dominant left. We tested whether an intonation-based speech therapy (i.e., melodic intonation therapy [MIT]), which is typically administered in an intense fashion with 75-80 daily therapy sessions, would lead to changes in white-matter tracts, particularly the AF. Using diffusion tensor imaging (DTI), we found a significant increase in the number of AF fibers and AF volume comparing post- with pretreatment assessments in six patients that could not be attributed to scan-to-scan variability. This suggests that intense, long-term MIT leads to remodeling of the right AF and may provide an explanation for the sustained therapy effects that were seen in these six patients.

Perceiving pitch absolutely: comparing absolute and relative pitch possessors in a pitch memory task

BACKGROUND

The perceptual-cognitive mechanisms and neural correlates of Absolute Pitch (AP) are not fully understood. The aim of this fMRI study was to examine the neural network underlying AP using a pitch memory experiment and contrasting two groups of musicians with each other, those that have AP and those that do not.

RESULTS

We found a common activation pattern for both groups that included the superior temporal gyrus (STG) extending into the adjacent superior temporal sulcus (STS), the inferior parietal lobule (IPL) extending into the adjacent intraparietal sulcus (IPS), the posterior part of the inferior frontal gyrus (IFG), the pre-supplementary motor area (pre-SMA), and superior lateral cerebellar regions. Significant between-group differences were seen in the left STS during the early encoding phase of the pitch memory task (more activation in AP musicians) and in the right superior parietal lobule (SPL)/intraparietal sulcus (IPS) during the early perceptual phase (ITP 0-3) and later working memory/multimodal encoding phase of the pitch memory task (more activation in non-AP musicians). Non-significant between-group trends were seen in the posterior IFG (more in AP musicians) and the IPL (more anterior activations in the non-AP group and more posterior activations in the AP group).

CONCLUSION

Since the increased activation of the left STS in AP musicians was observed during the early perceptual encoding phase and since the STS has been shown to be involved in categorization tasks, its activation might suggest that AP musicians involve categorization regions in tonal tasks. The increased activation of the right SPL/IPS in non-AP musicians indicates either an increased use of regions that are part of a tonal working memory (WM) network, or the use of a multimodal encoding strategy such as the utilization of a visual-spatial mapping scheme (i.e., imagining notes on a staff or using a spatial coding for their relative pitch height) for pitch information.

Eyes wide shut: amygdala mediates eyes-closed effect on emotional experience with music

The perceived emotional value of stimuli and, as a consequence the subjective emotional experience with them, can be affected by context-dependent styles of processing. Therefore, the investigation of the neural correlates of emotional experience requires accounting for such a variable, a matter of an experimental challenge. Closing the eyes affects the style of attending to auditory stimuli by modifying the perceptual relationship with the environment without changing the stimulus itself. In the current study, we used fMRI to characterize the neural mediators of such modification on the experience of emotionality in music. We assumed that closed eyes position will reveal interplay between different levels of neural processing of emotions. More specifically, we focused on the amygdala as a central node of the limbic system and on its co-activation with the Locus Ceruleus (LC) and Ventral Prefrontal Cortex (VPFC); regions involved in processing of, respectively, 'low', visceral-, and 'high', cognitive-related, values of emotional stimuli. Fifteen healthy subjects listened to negative and neutral music excerpts with eyes closed or open. As expected, behavioral results showed that closing the eyes while listening to emotional music resulted in enhanced rating of emotionality, specifically of negative music. In correspondence, fMRI results showed greater activation in the amygdala when subjects listened to the emotional music with eyes closed relative to eyes open. More so, by using voxel-based correlation and a dynamic causal model analyses we demonstrated that increased amygdala activation to negative music with eyes closed led to increased activations in the LC and VPFC. This finding supports a system-based model of perceived emotionality in which the amygdala has a central role in mediating the effect of context-based processing style by recruiting neural operations involved in both visceral (i.e. 'low') and cognitive (i.e. 'high') related processes of emotions.

Musical training shapes structural brain development

The human brain has the remarkable capacity to alter in response to environmental demands. Training-induced structural brain changes have been demonstrated in the healthy adult human brain. However, no study has yet directly related structural brain changes to behavioral changes in the developing brain, addressing the question of whether structural brain differences seen in adults (comparing experts with matched controls) are a product of "nature" (via biological brain predispositions) or "nurture" (via early training). Long-term instrumental music training is an intense, multisensory, and motor experience and offers an ideal opportunity to study structural brain plasticity in the developing brain in correlation with behavioral changes induced by training. Here we demonstrate structural brain changes after only 15 months of musical training in early childhood, which were correlated with improvements in musically relevant motor and auditory skills. These findings shed light on brain plasticity and suggest that structural brain differences in adult experts (whether musicians or experts in other areas) are likely due to training-induced brain plasticity.

Decrease in early right alpha band phase synchronization and late gamma band oscillations in processing syntax in music

The present study investigated the neural correlates associated with the processing of music-syntactical irregularities as compared with regular syntactic structures in music. Previous studies reported an early ( approximately 200 ms) right anterior negative component (ERAN) by traditional event-related-potential analysis during music-syntactical irregularities, yet little is known about the underlying oscillatory and synchronization properties of brain responses which are supposed to play a crucial role in general cognition including music perception. First we showed that the ERAN was primarily represented by low frequency (<8 Hz) brain oscillations. Further, we found that music-syntactical irregularities as compared with music-syntactical regularities, were associated with (i) an early decrease in the alpha band (9-10 Hz) phase synchronization between right fronto-central and left temporal brain regions, and (ii) a late ( approximately 500 ms) decrease in gamma band (38-50 Hz) oscillations over fronto-central brain regions. These results indicate a weaker degree of long-range integration when the musical expectancy is violated. In summary, our results reveal neural mechanisms of music-syntactic processing that operate at different levels of cortical integration, ranging from early decrease in long-range alpha phase synchronization to late local gamma oscillations.

Musical training shapes structural brain development

The human brain has the remarkable capacity to alter in response to environmental demands. Training-induced structural brain changes have been demonstrated in the healthy adult human brain. However, no study has yet directly related structural brain changes to behavioral changes in the developing brain, addressing the question of whether structural brain differences seen in adults (comparing experts with matched controls) are a product of "nature" (via biological brain predispositions) or "nurture" (via early training). Long-term instrumental music training is an intense, multisensory, and motor experience and offers an ideal opportunity to study structural brain plasticity in the developing brain in correlation with behavioral changes induced by training. Here we demonstrate structural brain changes after only 15 months of musical training in early childhood, which were correlated with improvements in musically relevant motor and auditory skills. These findings shed light on brain plasticity and suggest that structural brain differences in adult experts (whether musicians or experts in other areas) are likely due to training-induced brain plasticity.

Cultural constraints on music perception and cognition

Research suggests that music, like language, is both a biological predisposition and a cultural universal. While humans naturally attend to and process many of the psychophysical cues present in musical information, there is a great - and often culture-specific - diversity of musical practices differentiated in part by form, timbre, pitch, rhythm, and other structural elements. Musical interactions situated within a given cultural context begin to influence human responses to music as early as one year of age. Despite the world's diversity of musical cultures, the majority of research in cognitive psychology and the cognitive neuroscience of music has been conducted on subjects and stimuli from Western music cultures. From the standpoint of cognitive neuroscience, identification of fundamental cognitive and neurological processes associated with music requires ascertaining that such processes are demonstrated by listeners from a broad range of cultural backgrounds and in relation to various musics across cultural traditions. This chapter will review current research regarding the role of enculturation in music perception and cognition and the degree to which cultural influences are reflected in brain function. Exploring music cognition from the standpoint of culture will lead to a better understanding of the core processes underlying perception and how those processes give rise to the world's diversity of music forms and expressions.

Neuroanatomical correlates of musicianship as revealed by cortical thickness and voxel-based morphometry

We used a multimethod approach to investigate the neuroanatomical correlates of musicianship and absolute pitch (AP). Cortical thickness measures, interregional correlations applied to these thicknesses, and voxel-based morphometry (VBM) were applied to the same magnetic resonance imaging data set of 71 musicians (27 with AP) and 64 nonmusicians. Cortical thickness was greater in musicians with peaks in superior temporal and dorsolateral frontal regions. Correlations between 2 seed points, centered on peaks of thickness difference within the right frontal cortex, and all other points across the cortex showed greater specificity of significant correlations among musicians, with fewer and more discrete areas correlating with the frontal seeds, including the superior temporal cortex. VBM of gray matter (GM)-classified voxels yielded a strongly right-lateralized focus of greater GM concentration in musicians centered on the posterolateral aspect of Heschl's gyrus. Together, these results are consistent with functional evidence emphasizing the importance of a frontotemporal network of areas heavily relied upon in the performance of musical tasks. Among musicians, contrasts of AP possessors and nonpossessors showed significantly thinner cortex among possessors in a number of areas, including the posterior dorsal frontal cortices that have been previously implicated in the performance of AP tasks.

Musical expectancy: The influence of musical structure on emotional response

When examining how emotions are evoked through music, the role of musical expectancy is often surprisingly under-credited. This mechanism, however, is most strongly tied to the actual structure of the music, and thus is important when considering how music elicits emotions. We briefly summarize Leonard Meyer's theoretical framework on musical expectancy and emotion and cite relevant research in the area.

Musical training influences linguistic abilities in 8-year-old children: more evidence for brain plasticity

We conducted a longitudinal study with 32 nonmusician children over 9 months to determine 1) whether functional differences between musician and nonmusician children reflect specific predispositions for music or result from musical training and 2) whether musical training improves nonmusical brain functions such as reading and linguistic pitch processing. Event-related brain potentials were recorded while 8-year-old children performed tasks designed to test the hypothesis that musical training improves pitch processing not only in music but also in speech. Following the first testing sessions nonmusician children were pseudorandomly assigned to music or to painting training for 6 months and were tested again after training using the same tests. After musical (but not painting) training, children showed enhanced reading and pitch discrimination abilities in speech. Remarkably, 6 months of musical training thus suffices to significantly improve behavior and to influence the development of neural processes as reflected in specific pattern of brain waves. These results reveal positive transfer from music to speech and highlight the influence of musical training. Finally, they demonstrate brain plasticity in showing that relatively short periods of training have strong consequences on the functional organization of the children's brain.

Ritual harmony: Toward an evolutionary theory of music

Juslin & Västfjäll (J&V) advance our understanding of the proximate mechanisms underlying emotional responses to music, but fail to integrate their findings into a comprehensive evolutionary model that addresses the adaptive functions of these responses. Here we offer such a model by examining the ontogenetic relationship between music, ritual, and symbolic abstraction and their role in facilitating social coordination and cooperation.

Harmonic priming in an amusic patient: the power of implicit tasks

Our study investigated with an implicit method (i.e., priming paradigm) whether I.R. - a brain-damaged patient exhibiting severe amusia - processes implicitly musical structures. The task consisted in identifying one of two phonemes (Experiment 1) or timbres (Experiment 2) on the last chord of eight-chord sequences (i.e., target). The targets were harmonically related or less related to the prior chords. I.R. displayed harmonic priming effects: Phoneme and timbre identification was faster for related than for less related targets (Experiments 1 and 2). However, I.R.'s explicit judgements of completion for the same sequences did not differ between related and less related contexts (Experiment 3). Her impaired performance in explicit judgements was not due to general difficulties with task demands since she performed like controls for completion judgements on spoken sentences (Experiment 4). The findings indicate that implicit knowledge of musical structures might remain intact and accessible, even when explicit judgements and overt recognition have been lost.

Cross-cultural music phrase processing: an fMRI study

The current study used functional magnetic resonance imaging (fMRI) to investigate the neural basis of musical phrase boundary processing during the perception of music from native and non-native cultures. German musicians performed a cultural categorization task while listening to phrased Western (native) and Chinese (non-native) musical excerpts as well as modified versions of these, where the impression of phrasing has been reduced by removing the phrase boundary marking pause (henceforth called "unphrased"). Bilateral planum temporale was found to be associated with an increased difficulty of identifying phrase boundaries in unphrased Western melodies. A network involving frontal and parietal regions showed increased activation for the phrased condition with the orbital part of left inferior frontal gyrus presumably reflecting working memory aspects of the temporal integration between phrases, and the middle frontal gyrus and intraparietal sulcus probably reflecting attention processes. Areas more active in the culturally familiar, native (Western) condition included, in addition to the left planum temporale and right ventro-medial prefrontal cortex, mainly the bilateral motor regions. These latter results are interpreted in light of sensorimotor integration. Regions with increased signal for the unfamiliar, non-native music style (Chinese) included a right lateralized network of angular gyrus and the middle frontal gyrus, possibly reflecting higher demands on attention systems, and the right posterior insula suggesting higher loads on basic auditory processing.

From Singing to Speaking: Why Singing May Lead to Recovery of Expressive Language Function in Patients with Broca's Aphasia

It has been reported that patients with severely nonfluent aphasia are better at singing lyrics than speaking the same words. This observation inspired the development of Melodic Intonation Therapy (MIT), a treatment whose effects have been shown, but whose efficacy is unproven and neural correlates remain unidentified. Because of its potential to engage/unmask language-capable regions in the unaffected right hemisphere, MIT is particularly well suited for patients with large left-hemisphere lesions. Using two patients with similar impairments and stroke size/location, we show the effects of MIT and a control intervention. Both interventions' post-treatment outcomes revealed significant improvement in propositional speech that generalized to unpracticed words and phrases; however, the MIT-treated patient's gains surpassed those of the control-treated patient. Treatment-associated imaging changes indicate that MIT's unique engagement of the right hemisphere, both through singing and tapping with the left hand to prime the sensorimotor and premotor cortices for articulation, accounts for its effect over nonintoned speech therapy.

Neural substrates of spontaneous musical performance: an FMRI study of jazz improvisation

To investigate the neural substrates that underlie spontaneous musical performance, we examined improvisation in professional jazz pianists using functional MRI. By employing two paradigms that differed widely in musical complexity, we found that improvisation (compared to production of over-learned musical sequences) was consistently characterized by a dissociated pattern of activity in the prefrontal cortex: extensive deactivation of dorsolateral prefrontal and lateral orbital regions with focal activation of the medial prefrontal (frontal polar) cortex. Such a pattern may reflect a combination of psychological processes required for spontaneous improvisation, in which internally motivated, stimulus-independent behaviors unfold in the absence of central processes that typically mediate self-monitoring and conscious volitional control of ongoing performance. Changes in prefrontal activity during improvisation were accompanied by widespread activation of neocortical sensorimotor areas (that mediate the organization and execution of musical performance) as well as deactivation of limbic structures (that regulate motivation and emotional tone). This distributed neural pattern may provide a cognitive context that enables the emergence of spontaneous creative activity.

On experimenting with functional magnetic resonance imaging of lip movement

The analysis of functional magnetic resonance imaging (fMRI) time-series data can provide information on task-related activities, functional/effective connectivity among regions and the influences of behavioral/physiologic states on connectivity. This paper illustrates the importance of the neurobiological constraints involved in using statistical parametric mapping (SPM) through Matlab simulation and thus helping the radiologist to interpret the results better. This paper also presents the results and inferences from neuroimaging data of the lip movement experiment using statistical parametric mapping (SPM). The results match with the sensory/motor activation atlas by Penfield and Rasmussen (1950).

The influence of Mozart's sonata K.448 on visual attention: an ERPs study

In the present study, the effects of Mozart's sonata K.448 on voluntary and involuntary attention were investigated by recording and analyzing behavioral and event-related potentials (ERPs) data in a three-stimulus visual oddball task. P3a (related to involuntary attention) and P3b (related to voluntary attention) were analyzed. The "Mozart effect" was showed on ERP but not on behavioral data. This study replicated the previous results of Mozart effect on voluntary attention: the P3b latency was influenced by Mozart's sonata K.448. But no change of P3a latency was induced by this music. At the same time, decreased P3a and P3b amplitudes in music condition were found. We interpret this change as positive "Mozart effect" on involuntary attention (P3a) and negative "Mozart effect" on voluntary attention (P3b). We conclude that Mozart's sonata K.448 has shown certain effects on both involuntary attention and voluntary attention in our study, but their effects work on different mechanisms.

Musicians detect pitch violation in a foreign language better than nonmusicians: behavioral and electrophysiological evidence

The aim of this study was to determine whether musical expertise influences the detection of pitch variations in a foreign language that participants did not understand. To this end, French adults, musicians and nonmusicians, were presented with sentences spoken in Portuguese. The final words of the sentences were prosodically congruous (spoken at normal pitch height) or incongruous (pitch was increased by 35% or 120%). Results showed that when the pitch deviations were small and difficult to detect (35%: weak prosodic incongruities), the level of performance was higher for musicians than for nonmusicians. Moreover, analysis of the time course of pitch processing, as revealed by the event-related brain potentials to the prosodically congruous and incongruous sentence-final words, showed that musicians were, on average, 300 msec faster than nonmusicians to categorize prosodically congruous and incongruous endings. These results are in line with previous ones showing that musical expertise, by increasing discrimination of pitch--a basic acoustic parameter equally important for music and speech prosody--does facilitate the processing of pitch variations not only in music but also in language. Finally, comparison with previous results [Schön, D., Magne, C., & Besson, M. The music of speech: Music training facilitates pitch processing in both music and language. Psychophysiology, 41, 341-349, 2004] points to the influence of semantics on the perception of acoustic prosodic cues.

Neural correlates of the Pythagorean ratio rules

Millennia ago Pythagoras noted a simple but remarkably powerful rule for the aesthetics of tone combinations: pairs of tones--intervals--with simple ratios such as an octave (ratio 2 : 1) or a fifth (ratio 3 : 2) were pleasant sounding (consonant), whereas intervals with complex ratios such as the major seventh (ratio 243 : 128) were harsh (dissonant). These Pythagorean ratio rules are the building blocks of Western classical music; however, their neurophysiologic basis is not known. Using functional MRI we have found the neurophysiologic correlates of the ratio rules. In musicians, the inferior frontal gyrus, superior temporal gyrus, medial frontal gyrus, inferior parietal lobule and anterior cingulate respond with progressively more activation to perfect consonances, imperfect consonances and dissonances. In nonmusicians only the right inferior frontal gyrus follows this pattern.

Effects of music training on the child's brain and cognitive development

Research has revealed structural and functional differences in the brains of adult instrumental musicians compared to those of matched nonmusician controls, with intensity/duration of instrumental training and practice being important predictors of these differences. Nevertheless, the differential contributions of nature and nurture to these differences are not yet clear. The musician-nonmusician comparison is an ideal model for examining whether and, if so, where such functional and structural brain plasticity occurs, because musicians acquire and continuously practice a variety of complex motor, auditory, and multimodal skills (e.g., translating visually perceived musical symbols into motor commands while simultaneously monitoring instrumental output and receiving multisensory feedback). Research has also demonstrated that music training in children results in long-term enhancement of visual-spatial, verbal, and mathematical performance. However, the underlying neural bases of such enhancements and whether the intensity and duration of instrumental training or other factors, such as extracurricular activities, attention, motivation, or instructional methods can contribute to or predict these enhancements are yet unknown. Here we report the initial results from our studies examining the brain and cognitive effects of instrumental music training on young children in a longitudinal study and a cross-sectional comparison in older children. Further, we present a comparison of the results in these children's studies with observations from our cross-sectional studies with adults.

Implicit investigations of tonal knowledge in nonmusician listeners

By mere exposure to musical pieces in everyday life, Western listeners acquire sensitivity to the regularities of the tonal system and to the context dependency of musical sounds. This implicitly acquired tonal knowledge allows nonmusician listeners to perceive relationships among musical events and to develop expectations for future events that then influence the processing of these events. The musical priming paradigm is one method of the indirect investigation of listeners' tonal knowledge. It investigates the influence of a preceding context (with its musical structures and relationships) on the processing of a musical target event, without asking participants for direct evaluations. Behavioral priming data have provided evidence for facilitated processing of musically related events in comparison to unrelated and less-related events. The sensitivity of implicit investigations is further shown by I.R., a patient with severe amusia, showing spared implicit knowledge of music. Finally, the priming paradigm allows us to investigate the neural correlates of musical structure processing. Two fMRI studies reported the implication of inferior frontal regions in musical priming, contrasting related and unrelated events, as well as finer structural manipulations contrasting in-key events.

Emotional processing of harmonic expectancy violations

This study is about whether harmonic expectancy violations can trigger emotional processes, as indexed by physiological and subjective measures.

Shared and distinct neural correlates of singing and speaking

Using a modified sparse temporal sampling fMRI technique, we examined both shared and distinct neural correlates of singing and speaking. In the experimental conditions, 10 right-handed subjects were asked to repeat intoned ("sung") and non-intoned ("spoken") bisyllabic words/phrases that were contrasted with conditions controlling for pitch ("humming") and the basic motor processes associated with vocalization ("vowel production"). Areas of activation common to all tasks included the inferior pre- and post-central gyrus, superior temporal gyrus (STG), and superior temporal sulcus (STS) bilaterally, indicating a large shared network for motor preparation and execution as well as sensory feedback/control for vocal production. The speaking more than vowel-production contrast revealed activation in the inferior frontal gyrus most likely related to motor planning and preparation, in the primary sensorimotor cortex related to motor execution, and the middle and posterior STG/STS related to sensory feedback. The singing more than speaking contrast revealed additional activation in the mid-portions of the STG (more strongly on the right than left) and the most inferior and middle portions of the primary sensorimotor cortex. Our results suggest a bihemispheric network for vocal production regardless of whether the words/phrases were intoned or spoken. Furthermore, singing more than humming ("intoned speaking") showed additional right-lateralized activation of the superior temporal gyrus, inferior central operculum, and inferior frontal gyrus which may offer an explanation for the clinical observation that patients with non-fluent aphasia due to left hemisphere lesions are able to sing the text of a song while they are unable to speak the same words.

The Role of Harmonic Expectancy Violations in Musical Emotions: Evidence from Subjective, Physiological, and Neural Responses

The purpose of the present study was to investigate the effect of harmonic expectancy violations on emotions. Subjective response measures for tension and emotionality, as well as electrodermal activity (EDA) and heart rate (HR), were recorded from 24 subjects (12 musicians and 12 nonmusicians) to observe the effect of expectancy violations on subjective and physiological measures of emotions. In addition, an electro-encephalogram was recorded to observe the neural correlates for detecting these violations. Stimuli consisted of three matched versions of six Bach chorales, which differed only in terms of one chord (harmonically either expected, unexpected or very unexpected). Musicians' and nonmusicians' responses were also compared. Tension, overall subjective emotionality, and EDA increased with an increase in harmonic unexpectedness. Analysis of the event-related potentials revealed an early negativity (EN) for both the unexpected and the very unexpected harmonies, taken to reflect the detection of the unexpected event. The EN in response to very unexpected chords was significantly larger in amplitude than the EN in response to merely unexpected harmonic events. The ENs did not differ in amplitude between the two groups but peaked earlier for musicians than for nonmusicians. Both groups also showed a P3 component in response to the very unexpected harmonies, which was considerably larger for musicians and may reflect the processing of stylistic violations of Western classical music.

Auditory processing during deep propofol sedation and recovery from unconsciousness

OBJECTIVE

Using evoked potentials, this study investigated effects of deep propofol sedation, and effects of recovery from unconsciousness, on the processing of auditory information with stimuli suited to elicit a physical MMN, and a (music-syntactic) ERAN.

METHODS

Levels of sedation were assessed using the Bispectral Index (BIS) and the Modified Observer's Assessment of Alertness and Sedation Scale (MOAAS). EEG-measurements were performed during wakefulness, deep propofol sedation (MOAAS 2-3, mean BIS=68), and a recovery period. Between deep sedation and recovery period, the infusion rate of propofol was increased to achieve unconsciousness (MOAAS 0-1, mean BIS=35); EEG measurements of recovery period were performed after subjects regained consciousness.

RESULTS

During deep sedation, the physical MMN was markedly reduced, but still significant. No ERAN was observed in this level. A clear P3a was elicited during deep sedation by those deviants, which were task-relevant during the awake state. As soon as subjects regained consciousness during the recovery period, a normal MMN was elicited. By contrast, the P3a was absent in the recovery period, and the P3b was markedly reduced.

CONCLUSIONS

Results indicate that the auditory sensory memory (as indexed by the physical MMN) is still active, although strongly reduced, during deep sedation (MOAAS 2-3). The presence of the P3a indicates that attention-related processes are still operating during this level. Processes of syntactic analysis appear to be abolished during deep sedation. After propofol-induced anesthesia, the auditory sensory memory appears to operate normal as soon as subjects regain consciousness, whereas the attention-related processes indexed by P3a and P3b are markedly impaired.

SIGNIFICANCE

Results inform about effects of sedative drugs on auditory and attention-related mechanisms. The findings are important because these mechanisms are prerequisites for auditory awareness, auditory learning and memory, as well as language perception during anesthesia.

Cognitive priming in sung and instrumental music: Activation of inferior frontal cortex

Neural correlates of the processing of musical syntax-like structures have been investigated via expectancy violation due to musically unrelated (i.e., unexpected) events in musical contexts. Previous studies reported the implication of inferior frontal cortex in musical structure processing. However - due to the strong musical manipulations - activations might be explained by sensory deviance detection or repetition priming. Our present study investigated neural correlates of musical structure processing with subtle musical violations in a musical priming paradigm. Instrumental and sung sequences ended on related and less-related musical targets. The material controlled sensory priming components, and differences in target processing required listeners' knowledge on musical structures. Participants were scanned with functional Magnetic Resonance Imaging (fMRI) while performing speeded phoneme and timbre identification judgments on the targets. Behavioral results acquired in the scanner replicated the facilitation effect of related over less-related targets. The blood oxygen level-dependent (BOLD) signal linked to target processing revealed activation of right inferior frontal areas (i.e., inferior frontal gyrus, frontal operculum, anterior insula) that was stronger for less-related than for related targets, and this was independent of the material carrying the musical structures. This outcome points to the implication of inferior frontal cortex in the processing of syntactic relations also for musical material and to its role in the processing and integration of sequential information over time. In addition to inferior frontal activation, increased activation was observed in orbital gyrus, temporal areas (anterior superior temporal gyrus, posterior superior temporal gyrus and sulcus, posterior middle temporal gyrus) and supramarginal gyrus.

Neural control of playing a reversed piano: empirical evidence for an unusual cortical organization of musical functions

Using functional magnetic imaging techniques and neuropsychological tests, we studied a young male musician (C.S.) who performs at a professional level both on a regular piano keyboard and on a reverse keyboard (reversed right to left). The participant was left-handed, had left dominance for language but, remarkably, right dominance for the control of piano playing on both keyboards. With respect to music perception, C.S. showed left-sided activation dominance within the left superior temporal sulcus, which is normally associated with higher order auditory processing and right-sided activations in the secondary sensory cortex extending into the supramarginal gyrus. We suggest that C.S.'s pattern of functional asymmetry, characterized by audio-motor control using a right-sided network, could be a factor in his exceptional piano-playing ability on both the standard and reversed keyboard.

Musical training and language-related brain electrical activity in children

This experiment aimed at testing whether 8 weeks of musical training affect the ability of 8-year-old children to detect pitch changes in language. Twenty nonmusician children listened to linguistic phrases that ended with prosodically congruous words or with weak or strong pitch incongruities. We recorded reaction times, error rates, and event-related brain potentials to the final words. Half of the children followed music training and the other half painting training, and all children were retested following training. For both groups, the weak incongruity was the most difficult to detect, but performance was not significantly different between groups. However, the amplitude of a late positive component was largest to strong incongruities and was reduced after training only in the music group. These results suggest that a relatively short exposure to pitch processing in music exerts some influence on pitch processing in language.

Investigating emotion with music: an fMRI study

The present study used pleasant and unpleasant music to evoke emotion and functional magnetic resonance imaging (fMRI) to determine neural correlates of emotion processing. Unpleasant (permanently dissonant) music contrasted with pleasant (consonant) music showed activations of amygdala, hippocampus, parahippocampal gyrus, and temporal poles. These structures have previously been implicated in the emotional processing of stimuli with (negative) emotional valence; the present data show that a cerebral network comprising these structures can be activated during the perception of auditory (musical) information. Pleasant (contrasted to unpleasant) music showed activations of the inferior frontal gyrus (IFG, inferior Brodmann's area (BA) 44, BA 45, and BA 46), the anterior superior insula, the ventral striatum, Heschl's gyrus, and the Rolandic operculum. IFG activations appear to reflect processes of music-syntactic analysis and working memory operations. Activations of Rolandic opercular areas possibly reflect the activation of mirror-function mechanisms during the perception of the pleasant tunes. Rolandic operculum, anterior superior insula, and ventral striatum may form a motor-related circuitry that serves the formation of (premotor) representations for vocal sound production during the perception of pleasant auditory information. In all of the mentioned structures, except the hippocampus, activations increased over time during the presentation of the musical stimuli, indicating that the effects of emotion processing have temporal dynamics; the temporal dynamics of emotion have so far mainly been neglected in the functional imaging literature.