Music-Evoked Emotions-Current Studies

Abstract

The present study is focused on a review of the current state of investigating music-evoked emotions experimentally, theoretically and with respect to their therapeutic potentials. After a concise historical overview and a schematic of the hearing mechanisms, experimental studies on music listeners and on music performers are discussed, starting with the presentation of characteristic musical stimuli and the basic features of tomographic imaging of emotional activation in the brain, such as functional magnetic resonance imaging (fMRI) and positron emission tomography (PET), which offer high spatial resolution in the millimeter range. The progress in correlating activation imaging in the brain to the psychological understanding of music-evoked emotion is demonstrated and some prospects for future research are outlined. Research in psychoneuroendocrinology and molecular markers is reviewed in the context of music-evoked emotions and the results indicate that the research in this area should be intensified. An assessment of studies involving measuring techniques with high temporal resolution down to the 10 ms range, as, e.g., electroencephalography (EEG), event-related brain potentials (ERP), magnetoencephalography (MEG), skin conductance response (SCR), finger temperature, and goose bump development (piloerection) can yield information on the dynamics and kinetics of emotion. Genetic investigations reviewed suggest the heredity transmission of a predilection for music. Theoretical approaches to musical emotion are directed to a unified model for experimental neurological evidence and aesthetic judgment. Finally, the reports on musical therapy are briefly outlined. The study concludes with an outlook on emerging technologies and future research fields.

Keywords: EEG; emotions; fMRI; music; music therapy.

Figure 1

Extract from the aria Quell' usignolo of Geminiano Giacomelli's (1692-1740) opera Merope (1734) sung by Carlo Broschi Farinelli (1705-1782) for Philipp V (1683-1746), king of Spain (Haböck, 1923). Reprinted with permission from Haböck (1923) © 1923 Universal Edition.

Figure 2

Anatomy of the ear. Reprinted with permission from William E. Brownell © 2016. (B) Components of the inner ear. Reprinted with permission from © 2016 Encyclopedia Britannica. (C) Confocal micrographs of rat auditory hair cells. Scale bar: 1 μm. The protein myosin XVa is localized to the stereocilia tips (Rzadzinska et al., 2004). Reprinted with permission from Rzadzinska et al. (2004) © 2016 Bechara Kachar.

Figure 3

This graph shows the context-dependent bigram probabilities for the corpus of Bach chorales. Blue bars show probabilities of chord functions following the tonic (I), green bars following the submediant (vi), and red bars following a dominant (V). The probability for, e.g., a tonic (I) following a dominant (V) is high, the entropy is low (Koelsch, 2014). Reprinted with permission from Koelsch (2014) © 2014 Nature Publishing Group.

Figure 4

(A) Principles of magnetic resonance tomography (Birbaumer and Schmidt, 2010). (a) The patient is moved into the center of the MRI scanner. (b) A strong homogeneous magnetic field aligns the magnetic moments of the protons in in the patient's body. (c) An RF-pulse excites the proton magnetic moments to precession which gives rise to an alternating voltage signal in the detector. (d) After the switching-off the RF-pulse the proton magnetic moments relax to the initial orientation. The relaxation times (see B) are measured. Reprinted with permission from Birbaumer and Schmidt (2010) © 2010 Springer. (B) Nuclear magnetic relaxation times T1 (top) and T2 (bottom) of hydrogen nuclei for various biological materials (Schnier and Mehlhorn, 2013). Reprinted with permission from Schnier and Mehlhorn (2013) © 2013 Phywe Systeme. (C) Spatial encoding of the local magnetic resonance information (Birbaumer and Schmidt, 2010). Due to a slicing (left) and finally a three-dimensional structuring (right) by means of gradient fields, the resonance frequency and the relaxation times can be assigned to a particular pixel. Reprinted with permission from Birbaumer and Schmidt (2010) © 2010 Springer.

Figure 5

(A) Chemical formulae of two compounds doped with the positron emitters ¹⁸F (left. http://de.wikipedia.org/wiki/Fluordesoxyglucose; 19.12.14) and ¹¹C (right; http://www.ncbi.nlm.nih.gov/books/NBK23614/ 19.12.14) for PET scans. (B) Principles of positron emission tomography (PET). Left: A positron is emitted from a radioactive nucleus and annihilated with electrons of the tissue emitting two colinear annihilation photons which are monitored by radiation detectors and checked for coincidence. Right: Multi-detector PET scanner taking images (slices) of the concentration of positron emitting isotopes in the brain and thereby measuring the emotional activity of brain sections (Birbaumer and Schmidt, 2010). Reprinted with permission from Birbaumer and Schmidt (2010) © 2010 Springer.

Figure 6

(A) Neural correlates of music-evoked emotions. A meta-analysis of brain-imaging studies that shows neural correlates of music-evoked emotions. A meta-analysis is a statistical analysis of a lager set of the analyses of earlier data. The meta -analysis indicates clusters of activities derived from numerous studies (for references see Koelsch, 2014) in the amygdala (SF, LB), the hippocampal formation (a), the left caudate nucleus with a maximum in the nucleus accumbens (NAc, b), pre-supplementary motor area (SMA), rostral cingulated zone (RCZ), orbifrontal cortex (OFC), and mediodorsal thalamus (MD, c), as well as in auditory regions (Heschls gyrus HG) and anterior superior temporal gyrus (aSTG, d). Additional limbic and paralimbic brain areas may contribute to music-evoked emotions. For details see Koelsch (2014). Reprinted with permission from Koelsch (2014) © 2014 Nature Publishing Group. (B) Structural formula of dopamine (http://de.wikipedia.org/wiki/Dopamin) downloaded19.12.14.

Figure 7

(A) Main pathways underlying autonomic and muscular responses to music. The cortex (AC) also projects to the orbifrontal cortex (OFC) and the cingulated cortex (projections not shown). Moreover, the amygdala (AMYG), the OFC and the cingulated cortex send numerous projections to the hypothalamus (not shown) and thus also exert influence on the endocrine system. ACC, anterior cingulate cortex; CN, cochlear nuclei; IC, inferior colliculus; M1, primary motor cortex; MCC, middle cingulate cortex; MGB, medial geniculate body; NAc, nucleus accumbens; PMC, premotor cortex; RCZ, rostral cingulated zone; VN, vestibular nuclei (Koelsch, 2014). Reprinted with permission from Koelsch (2014) © 2014 Nature Publishing Group. (B) Hippocampus. Reprinted with permission from Annie Krusznis © 2016.

Figure 8

Joyful instrumental dance-tunes of major-minor tonal music by Dvorak (1955) and Bach (1967) used from commercially available CDs as pleasant stimuli in Koelsch et al. (2006). Reprinted with permission from Bach (1967) © 1967 Bärenreiter.

Figure 9

(A) 5-hydroxytryptamine (serotonin) receptor 2A (5-HT_2A), G protein coupled; diameter of the protein alpha-helix ~0.5 nm https://en.wikipedia.org/wiki/5-HT2A_receptor downloaded 4. 10. 2016. (B) PET images showing decrease in ¹¹C-NMSP binding clusters (arrows) in a subject listening to frightening music: right caudate head, right frontal subgirus, and right anterior cingulated (A); left lateral globus pallidus and left caudate body (B); right anterior cingulated (C); and right superior temporal gyrus, right claustrum, and right amygdala. (D) (Zhang et al., 2012). Reprinted with permission from Zhang et al. (2012) © 2012 SNMMI. (C) PET images showing increase in 11C-NMSP binding clusters (arrows) in a subject listening to frightening music: right frontal lobe and middle frontal gyrus (A); right fusiform gyrus and right middle occipital gyrus (B); right superior occipital gyrus, right middle occipital gyrus (C); and left middle temporal gyrus (D) (Zhang et al., 2012). Reprinted with permission from Zhang et al. (2012) © 2012 SNMMI.

Figure 10

(A) Overt singing. The activation maps show activations of the bilateral sensorimotor cortex and the cerebellum, the bilateral auditory cortex, Broca's and Wernicke's areas, medulla, thalamus, and ventral striatum but also ACC and insula were activated. Coordinates of cuts are given above each slice (Kleber et al., 2007). Reprinted with permission from Kleber et al. (2007) © 2007 Elsevier. (B) Mental rehearsal of singing (imaginary singing). Activation of typical imagery regions such as sensorimotor areas (SMA), premotor cortex areas, thalamus, basal ganglia, and cerebellum. Areas processing emotions showed intense activation (ACC and insula, hippocampus, amygdala, and ventrolateral prefrontal cortex). Coordinates of cuts are given above each slice (Kleber et al., 2007). Reprinted with permission from Kleber et al. (2007) © 2007 Elsevier.

Figure 11

Neuroendocrine and immunological molecular markers released during music- evoked emotion (see Kreutz et al., 2012). The molecular masses are given in kDa = 1.66 × 10⁻²⁴ kg. http://en.wikipedia.org/wiki/Beta-endorphin#mediaviewer/File:Betaendorphin.png; http://de.wikipedia.org/wiki/Cortisol; http://de.wikipedia.org/wiki/Testosteron; http://de.wikipedia.org/wiki/Prolaktin; http://de.wikipedia.org/wiki/Oxytocin; http://en.wikipedia.org/wiki/Immunoglobulin_A downloads 20.12.2014.

Figure 12

Negative surface slow brain potentials on the skalp are generated by extracellular currents (red dashed arrows) which arise due to the electrical activation of apical dendrites by thalamocortical afferences (Birbaumer and Schmidt, 2010). Reprinted with permission from Birbaumer and Schmidt (2010) © 2010 Springer.

Figure 13

(A) Origin of the MEG signal. (a) Coronal section of the human brain with the cortex in dark color. The electrical currents flow roughly perpendicular to the cortex. (b) In the convoluted cortex with the sulci and gyri the currents flow either radially or tangentially (c) or radially (d) in the head. (e) The magnetic fields generated by the tangential currents can be detected outside the head (Vrba and Robinson, 2001). Reprinted with permission from Vrba and Robinson (2001) © 2001 Elsevier. (B) (a) Magnetoencephalography facility containing 150 magnetic field sensors. (b) SQUIDs (superconducting quantum interference devices) and sensors immersed for cooling in liquid helium contained in a Dewar vessel (cross section) (Birbaumer and Schmidt, 2010). Reprinted with permission from Birbaumer and Schmidt (2010) © 2010 Springer. (C) Cortical stimulation by pure and piano tones. Left: Medial–lateral coordinates are shown for single equivalent current dipoles fitted to the field patterns evoked by pure sine tones and piano tones in control subjects. The inset defines the coordinate system of the head. Right: Equivalent current dipoles (ECD) shift toward the sagittal midline along the medial–lateral coordinate as a function of the frequency of the tone. Ant–post, anterior–posterior; med–lat, medial–lateral; inf–sup, inferior–superior (Pantev et al., 1998). Reprinted with permission from Pantev et al. (1998) © 2001 Nature Publishing Group.

Figure 14

(A) The median curve of the skin conductance response (SCR) amplitude around the entrance of the chorus. The first downbeat was set to t = 0 s (Tsai et al., 2014). The two peaks are ascribed to the two closely related phases of listening experience: anticipatory “wanting” and hedonic “liking” of rewards. Reprinted with permission from Tsai et al. (2014) © 2014 Sage. (B) The u-shaped time-dependence of the finger temperatures of the listeners during presentation of the five songs. The end of the first chorus (see full dots) devides each song into two parts with a decrease of the finger temperature in the first part and an increase in the second part (Tsai et al., 2014). Reprinted with permission from Tsai et al. (2014) © 2014 Sage. The symbols ^*** and ^* indicate that the two peaks are significantly larger than the control data.

Figure 15

(A) Time-dependence of the relative piloerection intensity of a single experiment, including a baseline period (30 s), stimulus description (20 s) and stimulus presentation (variable duration). The initial stable level of piloerection intensity indicates no visible piloerection. In this experiment, piloerection occurs shortly after the onset of stimulus presentation; after some time it fades away. The asterisk marks the first detected onset of piloerection. This time is used for the short-term physiological response (Benedek and Kaernbach, 2011). Reprinted with permission from Benedek and Kaernbach (2011) © 2011 Elsevier. (B) Procedure of piloerection quantification without (top row) and with visible piloerection (bottom row). From B (bottom) a two-dimensional spatial Fourier transform is computed (C, shown for the frequency range ±1.13 mm⁻¹) which is converted to a one-dimensional spectrum of spatial frequency. The maximum spectral power in the 0.23–0.75 mm⁻¹ range (D) is considered as a correlate of the piloerection intensity (Benedek et al., 2010). Reprinted with permission from Benedek et al. (2010) © 2010 Wiley. (C) Time dependence of the short-term response of physiological measurements for a time slot of −15 s to +15 s around the first onset of piloerection. Dark bars indicate significant deviations from zero, white bars indicate non-significant deviations. ISCR-integrated skin conductance response, SCL-skin conductance level, HR-heart rate, PVA-pulse volume amplitude, RR-respiration rate, RD- respiration depth (Benedek and Kaernbach, 2011). Reprinted with permission from Benedek and Kaernbach (2011) © 2011 Elsevier.

Figure 16

(A) Mean values and standard errors for listeners' ratings of criteria for aesthetic value of music. (B) Individual ratings of criteria for aesthetic value of music by four subjects (see Juslin, 2013). Reprinted with permission from Juslin (2013) © 2013 Elsevier.

Figure 17

(A) Representative cryo electron micrographs of fusing vesicles (see arrows) in mouse hippocampal synapses at 15 ms (c) and 30 ms (d) after light onset (Watanabe et al., 2013). Reprinted with permission from Watanabe et al. (2013) © 2013 Nature Publishing Group. (B) STED (stimulated emission depletion) microscopy in the molecular layer of the somatosensory cortex of a mouse with EYFP-labeled neurons. (A) Anesthetized mouse under the objective lens. (B) Projected volumes of dendritic and axonal structures reveal (C) temporal dynamics of spine morphology with (D) an approximately four-fold improved spatial resolution compared with diffraction limited imaging. The curve is three-pixel-wide line profile fitted to raw data with a Gaussian. Scale bars, 1 μm (Berning et al., 2012). Reprinted with permission from Berning et al. (2012) © 2012 AAAS.