Manuela M. Marin

Reduced sensitivity to emotional prosody in congenital amusia rekindles the musical protolanguage hypothesis

A number of evolutionary theories assume that music and language have a common origin as an emotional protolanguage that remains evident in overlapping functions and shared neural circuitry. The most basic prediction of this hypothesis is that sensitivity to emotion in speech prosody derives from the capacity to process music. We examined sensitivity to emotion in speech prosody in a sample of individuals with congenital amusia, a neurodevelopmental disorder characterized by deficits in processing acoustic and structural attributes of music. Twelve individuals with congenital amusia and 12 matched control participants judged the emotional expressions of 96 spoken phrases. Phrases were semantically neutral but prosodic cues (tone of voice) communicated each of six emotional states: happy, tender, afraid, irritated, sad, and no emotion. Congenitally amusic individuals were significantly worse than matched controls at decoding emotional prosody, with decoding rates for some emotions up to 20% lower than that of matched controls. They also reported difficulty understanding emotional prosody in their daily lives, suggesting some awareness of this deficit. The findings support speculations that music and language share mechanisms that trigger emotional responses to acoustic attributes, as predicted by theories that propose a common evolutionary link between these domains.

Crossmodal transfer of arousal, but not pleasantness, from the musical to the visual domain.

Arousal and valence (pleasantness) are considered primary dimensions of emotion. However, the degree to which these dimensions interact in emotional processing across sensory modalities is poorly understood. We addressed this issue by applying a crossmodal priming paradigm in which auditory primes (Romantic piano solo music) varying in arousal and/or pleasantness were sequentially paired with visual targets (IAPS pictures). In Experiment 1, the emotion spaces of 120 primes and 120 targets were explored separately in addition to the effects of musical training and gender. Thirty-two participants rated their felt pleasantness and arousal in response to primes and targets on equivalent rating scales as well as their familiarity with the stimuli. Musical training was associated with elevated familiarity ratings for high-arousing music and a trend for elevated arousal ratings, especially in response to unpleasant musical stimuli. Males reported higher arousal than females for pleasant visual stimuli. In Experiment 2, 40 nonmusicians rated their felt arousal and pleasantness in response to 20 visual targets after listening to 80 musical primes. Arousal associated with the musical primes modulated felt arousal in response to visual targets, yet no such transfer of pleasantness was observed between the two modalities. Experiment 3 sought to rule out the possibility of any order effect of the subjective ratings, and responses of 14 nonmusicians replicated results of Experiment 2. This study demonstrates the effectiveness of the crossmodal priming paradigm in basic research on musical emotions.

Perception of musical timbre in congenital amusia: Categorization, discrimination and short-term memory

Congenital amusia is a neurodevelopmental disorder that is characterized primarily by difficulties in the pitch domain. The aim of the present study was to investigate the perception of musical timbre in a group of individuals with congenital amusia by probing discrimination and short-term memory for real-world timbral stimuli as well as examining the ability of these individuals to sort instrumental tones according to their timbral similarity. Thirteen amusic individuals were matched with thirteen non-amusic controls on a range of background variables. The discrimination task included stimuli of two different durations and pairings of instrumental tones that reflected varying distances in a perceptual timbre space. Performance in the discrimination task was at ceiling for both groups. In contrast, amusic individuals scored lower than controls on the short-term timbral memory task. Amusic individuals also performed worse than controls on the sorting task, suggesting differences in the higher-order representation of musical timbre. These findings add to the emerging picture of amusia as a disorder that has consequences for the perception and memory of musical timbre, as well as pitch.

Beyond intensity: Spectral features effectively predict music-induced subjective arousal

Emotions in music are conveyed by a variety of acoustic cues. Notably, the positive association between sound intensity and arousal has particular biological relevance. However, although amplitude normalization is a common procedure used to control for intensity in music psychology research, direct comparisons between emotional ratings of original and amplitude-normalized musical excerpts are lacking. In this study, 30 nonmusicians retrospectively rated the subjective arousal and pleasantness induced by 84 six-second classical music excerpts, and an additional 30 nonmusicians rated the same excerpts normalized for amplitude. Following the cue-redundancy and Brunswik lens models of acoustic communication, we hypothesized that arousal and pleasantness ratings would be similar for both versions of the excerpts, and that arousal could be predicted effectively by other acoustic cues besides intensity. Although the difference in mean arousal and pleasantness ratings between original and amplitude-normalized excerpts correlated significantly with the amplitude adjustment, ratings for both sets of excerpts were highly correlated and shared a similar range of values, thus validating the use of amplitude normalization in music emotion research. Two acoustic parameters, spectral flux and spectral entropy, accounted for 65% of the variance in arousal ratings for both sets, indicating that spectral features can effectively predict arousal. Additionally, we confirmed that amplitude-normalized excerpts were adequately matched for loudness. Overall, the results corroborate our hypotheses and support the cue-redundancy and Brunswik lens models.

Crossing boundaries: toward a general model of neuroaesthetics.

Since its dawn in the early 2000s, neuroaesthetics has been flowering as an independent research field (Nadal and Skov, 2013). Its emergence has mostly been driven by researchers who specialize in the study of visual perception and cognition, and who show interest in visual arts. This strong link between neuroaesthetics and vision science is reflected not only by the fact that the term “neuroaesthetics” was coined by the renowned vision researcher Semir Zeki (Zeki and Nash, 1999), but also by recent reviews on neuroaesthetics focusing primarily on aesthetic experiences induced by paintings, abstract patterns, landscapes, faces, architecture, fashion and design objects (Cinzia and Vittorio, 2009; Cela-Conde et al., 2011; Chatterjee, 2011, 2014; Nadal, 2013; Chatterjee and Vartanian, 2014). Current models of aesthetic experiences and their brain correlates revolve around the visual modality and include moderators of aesthetic experiences (social, cultural and situational context, personality, expertise etc.) (Ramachandran and Hirstein, 1999; Chatterjee, 2004; Tinio, 2013; Leder and Nadal, 2014; Redies, 2015). These models are not exclusively concerned with the study of beauty or preference, although these concepts are of historical importance, but include a wide range of aesthetic emotions, judgements, and behaviors.

The Eye is Listening: Music-Induced Arousal and Individual Differences Predict Pupillary Responses

Pupillary responses are a well-known indicator of emotional arousal but have not yet been systematically investigated in response to music. Here, we measured pupillary dilations evoked by short musical excerpts normalized for intensity and selected for their stylistic uniformity. Thirty participants (15 females) provided subjective ratings of music-induced felt arousal, tension, pleasantness, and familiarity for 80 classical music excerpts. The pupillary responses evoked by these excerpts were measured in another thirty participants (15 females). We probed the role of listener-specific characteristics such as mood, stress reactivity, self-reported role of music in life, liking for the selected excerpts, as well as of subjective responses to music, in pupillary responses. Linear mixed model analyses showed that a greater role of music in life was associated with larger dilations, and that larger dilations were also predicted for excerpts rated as more arousing or tense. However, an interaction between arousal and liking for the excerpts suggested that pupillary responses were modulated less strongly by arousal when the excerpts were particularly liked. An analogous interaction was observed between tension and liking. Additionally, males exhibited larger dilations than females. Overall, these findings suggest a complex interplay between bottom-up and top-down influences on pupillary responses to music.

Berlyne Revisited: Evidence for the Multifaceted Nature of Hedonic Tone in the Appreciation of Paintings and Music

In his seminal book on esthetics, Berlyne (1971) posited an inverted-U relationship between complexity and hedonic tone in arts appreciation, however, converging evidence for his theory is still missing. The disregard of the multidimensionality of complexity may explain some of the divergent results. Here, we argue that definitions of hedonic tone are manifold and systematically examined whether the nature of the relationship between complexity and hedonic tone is determined by the specific measure of hedonic tone. In Experiment 1, we studied three picture categories with similar affective and semantic contents: 96 affective environmental scenes, which were also converted into 96 cartoons, and 96 representational paintings. Complexity varied along the dimension of elements. In a between-subjects design, each stimulus was presented for 5 s to 206 female participants. Subjective ratings of hedonic tone (either beauty, pleasantness or liking), arousal, complexity and familiarity were collected in three conditions per stimulus set. Complexity and arousal were positively associated in all conditions, with the strongest association observed for paintings. For environmental scenes and cartoons, there was no significant association between complexity and hedonic tone, and the three measures of hedonic tone were highly correlated (all rs > 0.85). As predicted, in paintings the measures of hedonic tone were less strongly correlated (all rs > 0.73), and when controlling for familiarity, the association with complexity was significantly positive for beauty (rs = 0.26), weakly negative for pleasantness (rs = -0.16) and not present for liking. Experiment 2 followed a similar approach and 77 female participants, all non-musicians, rated 92 musical excerpts (15 s) in three conditions of hedonic tone (either beauty, pleasantness or liking). Results indicated a strong relationship between complexity and arousal (all rs > 0.85). When controlling for familiarity effects, the relationship between complexity and beauty followed an inverted-U curve, whereas the relationship between complexity and pleasantness was negative (rs = -0.26) and the one between complexity and liking positive (rs = 0.29). We relate our results to Berlyne’s theory and the latest findings in neuroaesthetics, proposing that future studies need to acknowledge the multifaceted nature of hedonic tone in esthetic experiences of artforms.

Evolutionary considerations on complex emotions and music-induced emotions: Comment on “The quartet theory of human emotions: An integrative and neurofunctional model” by S. Koelsch et al.

Recent efforts to uncover the neural underpinnings of emotional experiences have provided a foundation for novel neurophysiological theories of emotions, adding to the existing body of psychophysiological, motivational, and evolutionary theories. Besides explicitly modeling human-specific emotions and considering the interactions between emotions and language, Koelsch et al.’s original contribution to this challenging endeavor is to identify four brain areas as distinct “affect systems” which differ in terms of emotional qualia and evolutionary pathways [1]. Here, we comment on some features of this promising Quartet Theory of Emotions, focusing particularly on evolutionary and biological aspects related to the four affect systems and their relation to prevailing emotion theories, as well as on the role of music-induced emotions. The Quartet Theory’s emphasis on human emotions is a welcome feature. Nevertheless, we find the claim that complex social and moral emotions are uniquely human to be questionable in the face of recent literature reporting on a broad repertoire of complex emotions in animals [2,3]. Moreover, despite differences in the relative size of its various areas, the orbitofrontal cortex of monkeys and humans appears to have a similar architecture and connectivity with other parts of the brain [4]. However, current empirical evidence for a Theory of Mind in non-human primates remains conflicting [5]. Future research might consider differences between animals and humans on the basis of Haidt’s classification of moral emotions [6], which distinguishes between “Other-Condemning Emotions” (such as anger, contempt and disgust), “Self-Conscious Emotions” (shame and guilt), “Other-Suffering Emotions” (distress and empathy), and “Other-Praising Emotions” (gratitude). A further step would be the integration of basic and complex emotions in animals and humans under a single theoretical framework, acknowledging that social emotions are likely more developed and prevalent in higher primates and especially in humans. This approach would be in line with evolutionary theories of emotion asserting that complex emotions encountered in social settings derive from interactions between basic emotions [7].

Misattribution of musical arousal increases sexual attraction towards opposite-sex faces in females

Several theories about the origins of music have emphasized its biological and social functions, including in courtship. Music may act as a courtship display due to its capacity to vary in complexity and emotional content. Support for music’s reproductive function comes from the recent finding that only women in the fertile phase of the reproductive cycle prefer composers of complex melodies to composers of simple ones as short-term sexual partners, which is also in line with the ovulatory shift hypothesis. However, the precise mechanisms by which music may influence sexual attraction are unknown, specifically how music may interact with visual attractiveness cues and affect perception and behaviour in both genders. Using a crossmodal priming paradigm, we examined whether listening to music influences ratings of facial attractiveness and dating desirability of opposite-sex faces. We also tested whether misattribution of arousal or pleasantness underlies these effects, and explored whether sex differences and menstrual cycle phase may be moderators. Our sample comprised 64 women in the fertile or infertile phase (no hormonal contraception use) and 32 men, carefully matched for mood, relationship status, and musical preferences. Musical primes (25 s) varied in arousal and pleasantness, and targets were photos of faces with neutral expressions (2 s). Group-wise analyses indicated that women, but not men, gave significantly higher ratings of facial attractiveness and dating desirability after having listened to music than in the silent control condition. High-arousing, complex music yielded the largest effects, suggesting that music may affect human courtship behaviour through induced arousal, which calls for further studies on the mechanisms by which music affects sexual attraction in real-life social contexts.