Stefan Koelsch

Musical syntax is processed in Broca's area: an MEG study

The present experiment was designed to localize the neural substrates that process music-syntactic incongruities, using magnetoencephalography (MEG). Electrically, such processing has been proposed to be indicated by early right-anterior negativity (ERAN), which is elicited by harmonically inappropriate chords occurring within a major-minor tonal context. In the present experiment, such chords elicited an early effect, taken as the magnetic equivalent of the ERAN (termed mERAN). The source of mERAN activity was localized in Brocas area and its right-hemisphere homologue, areas involved in syntactic analysis during auditory language comprehension. We find that these areas are also responsible for an analysis of incoming harmonic sequences, indicating that these regions process syntactic information that is less language-specific than previously believed.

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 Brodmanns area (BA) 44, BA 45, and BA 46), the anterior superior insula, the ventral striatum, Heschls 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. Hum Brain Mapp 2005.

Bach Speaks: A Cortical "Language-Network" Serves the Processing of Music

The aim of the present study was the investigation of neural correlates of music processing with fMRI. Chord sequences were presented to the participants, infrequently containing unexpected musical events. These events activated the areas of Broca and Wernicke, the superior temporal sulcus, Heschls gyrus, both planum polare and planum temporale, as well as the anterior superior insular cortices. Some of these brain structures have previously been shown to be involved in music processing, but the cortical network comprising all these structures has up to now been thought to be domain-specific for language processing. To what extent this network might also be activated by the processing of non-linguistic information has remained unknown. The present fMRI-data reveal that the human brain employs this neuronal network also for the processing of musical information, suggesting that the cortical network known to support language processing is less domain-specific than previously believed.

Brain Indices of Music Processing: Nonmusicians are Musical

Only little systematic research has examined event-related brain potentials (ERPs) elicited by the cognitive processing of music. The present study investigated how music processing is influenced by a preceding musical context, affected by the task relevance of unexpected chords, and influenced by the degree and the probability of violation. Four experiments were conducted in which nonmusicians listened to chord sequences, which infrequently contained a chord violating the sound expectancy of listeners. Integration of in-key chords into the musical context was reflected as a late negative-frontal deflection in the ERPs. This negative deflection declined towards the end of a chord sequence, reflecting normal buildup of musical context. Brain waves elicited by chords with unexpected notes revealed two ERP effects: an early right-hemispheric preponderant-anterior negativity, which was taken to reflect the violation of sound expectancy; and a late bilateral-frontal negativity. The late negativity was larger compared to in-key chords and taken to reflect the higher degree of integration needed for unexpected chords. The early right-anterior negativity (ERAN) was unaffected by the task relevance of unexpected chords. The amplitudes of both early and late negativities were found to be sensitive to the degree of musical expectancy induced by the preceding harmonic context, and to the probability for deviant acoustic events. The employed experimental design opens a new field for the investigation of music processing. Results strengthen the hypothesis of an implicit musical ability of the human brain.

Towards a neural basis of music perception

Music perception involves complex brain functions underlying acoustic analysis, auditory memory, auditory scene analysis, and processing of musical syntax and semantics. Moreover, music perception potentially affects emotion, influences the autonomic nervous system, the hormonal and immune systems, and activates (pre)motor representations. During the past few years, research activities on different aspects of music processing and their neural correlates have rapidly progressed. This article provides an overview of recent developments and a framework for the perceptual side of music processing. This framework lays out a model of the cognitive modules involved in music perception, and incorporates information about the time course of activity of some of these modules, as well as research findings about where in the brain these modules might be located.

Music, language and meaning: Brain signatures of semantic processing

Semantics is a key feature of language, but whether or not music can activate brain mechanisms related to the processing of semantic meaning is not known. We compared processing of semantic meaning in language and music, investigating the semantic priming effect as indexed by behavioral measures and by the N400 component of the event-related brain potential (ERP) measured by electroencephalography (EEG). Human subjects were presented visually with target words after hearing either a spoken sentence or a musical excerpt. Target words that were semantically unrelated to prime sentences elicited a larger N400 than did target words that were preceded by semantically related sentences. In addition, target words that were preceded by semantically unrelated musical primes showed a similar N400 effect, as compared to target words preceded by related musical primes. The N400 priming effect did not differ between language and music with respect to time course, strength or neural generators. Our results indicate that both music and language can prime the meaning of a word, and that music can, as language, determine physiological indices of semantic processing.

Superior pre-attentive auditory processing in musicians

The present study focuses on influences of long-term experience on auditory processing, providing the first evidence for pre-attentively superior auditory processing in musicians. This was revealed by the brains automatic change-detection response, which is reflected electrically as the mismatch negativity (MMN) and generated by the operation of sensoric (echoic) memory, the earliest cognitive memory system. Major chords and single tones were presented to both professional violinists and non-musicians under ignore and attend conditions. Slightly impure chords, presented among perfect major chords elicited a distinct MMN in professional musicians, but not in non-musicians. This demonstrates that compared to non-musicians, musicians are superior in pre-attentively extracting more information out of musically relevant stimuli. Since effects of long-term experience on pre-attentive auditory processing have so far been reported for language-specific phonemes only, results indicate that sensory memory mechanisms can be modulated by training on a more general level.

Universal Recognition of Three Basic Emotions in Music

It has long been debated which aspects of music perception are universal and which are developed only after exposure to a specific musical culture. Here, we report a crosscultural study with participants from a native African population (Mafa) and Western participants, with both groups being naive to the music of the other respective culture. Experiment 1 investigated the ability to recognize three basic emotions (happy, sad, scared/fearful) expressed in Western music. Results show that the Mafas recognized happy, sad, and scared/fearful Western music excerpts above chance, indicating that the expression of these basic emotions in Western music can be recognized universally. Experiment 2 examined how a spectral manipulation of original, naturalistic music affects the perceived pleasantness of music in Western as well as in Mafa listeners. The spectral manipulation modified, among other factors, the sensory dissonance of the music. The data show that both groups preferred original Western music and also original Mafa music over their spectrally manipulated versions. It is likely that the sensory dissonance produced by the spectral manipulation was at least partly responsible for this effect, suggesting that consonance and permanent sensory dissonance universally influence the perceived pleasantness of music.

Functional architecture of verbal and tonal working memory: An FMRI study

This study investigates the functional architecture of working memory (WM) for verbal and tonal information during rehearsal and articulatory suppression. Participants were presented with strings of four sung syllables with the task to remember either the pitches (tonal information) or the syllables (verbal information). Rehearsal of verbal, as well as of tonal information activated a network comprising ventrolateral premotor cortex (encroaching Brocas area), dorsal premotor cortex, the planum temporale, inferior parietal lobe, the anterior insula, subcortical structures (basal ganglia and thalamus), as well as the cerebellum. The topography of activations was virtually identical for the rehearsal of syllables and pitches, showing a remarkable overlap of the WM components for the rehearsal of verbal and tonal information. When the WM task was performed under articulatory suppression, activations in those areas decreased, while additional activations arose in anterior prefrontal areas. These prefrontal areas might contain additional storage components of verbal and tonal WM that are activated when auditory information cannot be rehearsed. As in the rehearsal conditions, the topography of activations under articulatory suppression was nearly identical for the verbal as compared to the tonal task. Results indicate that both the rehearsal of verbal and tonal information, as well as storage of verbal and tonal information relies on strongly overlapping neuronal networks. These networks appear to partly consist of sensorimotor‐related circuits which provide resources for the representation and maintenance of information, and which are remarkably similar for the production of speech and song. Hum Brain Mapp, 2009.

Neural substrates of processing syntax and semantics in music.

Growing evidence indicates that syntax and semantics are basic aspects of music. After the onset of a chord, initial music-syntactic processing can be observed at about 150-400 ms and processing of musical semantics at about 300-500 ms. Processing of musical syntax activates inferior frontolateral cortex, ventrolateral premotor cortex and presumably the anterior part of the superior temporal gyrus. These brain structures have been implicated in sequencing of complex auditory information, identification of structural relationships, and serial prediction. Processing of musical semantics appears to activate posterior temporal regions. The processes and brain structures involved in the perception of syntax and semantics in music have considerable overlap with those involved in language perception, underlining intimate links between music and language in the human brain.