A stimulus set of musical intervals of varying degrees of valence via the simultaneous manipulation of consonance and timbre
Consonance is considered to be a measure of pleasantness (e.g., Koelsch et al., 2006) but as yet researchers have not reached a consensus on how one defines consonance (e.g., Cazden, 1980; Parncutt & Hair, 2011; Tenney, 1988). Most often consonant musical intervals have been defined based on the simplicity of the ratio of the fundamental frequencies of notes (e.g., Gosselin et al., 2006; Trainor et al., 1998) or their harmonic content (e.g., McDermott et al., 2010). In the present set of stimuli, we manipulated consonance and specific acoustic properties so as to create sounds that elicited different degrees of valence. Specifically, we simultaneously manipulated the consonance/dissonance of musical intervals associated with musical rules (i.e., the simplicity of ratios of fundamental frequencies of tones) and the timbre of notes (i.e., the frequency components of tones). Thus, we created musical sounds that typically (i.e., according to musical rules) are consonant but are being perceived as unpleasant due to their harmonic content.
The development of this stimulus set was inspired by Tenney’s (1988) historical definitions of the concepts of consonance and dissonance -particularly the polyphonic and the psychoacoustic concepts- and was based on Sethares’ (2005) work demonstrating how one can create musical scales based on synthetic timbres so as to modulate ratings of pleasantness in musical intervals (e.g., change well known intervals of western music that are considered to be consonant to be perceived as highly unpleasant).
This stimulus set has been behaviorally validated in terms of valence (i.e., pleasantness/unpleasantness; Papavasileiou & Vatakis, in preparation; 2014) and ultimately can be used for the study of emotion with music as current literature is usually using complex music pieces with multiple levels of potential confounds (e.g., multiple acoustical parameters modified, memories associated with the music piece). The defining characteristic of this stimulus set that distinguishes it from other auditory stimuli used in research, is the implementation of two different consonance definitions, while the stimuli remain very simple and well defined in terms of their physical properties (e.g., power spectra; see ‘Stimulus Description’ file for more details).
References
Cazden, N. (1980). The definition of consonance and dissonance. International Review of the Aesthetics and Sociology of Music, 11(2), 123-168.
Gosselin, N., Samson, S., Adolphs, R., Noulhiane, M., Roy, M., Hasboun, D., & Peretz, I. (2006). Emotional responses to unpleasant music correlates with damage to the parahippocampal cortex. Brain, 129(10), 2585-2592.
Koelsch, S., Fritz, T., Müller, K., & Friederici, A. D. (2006). Investigating emotion with music: an fMRI study. Human Brain Mapping, 27(3), 239-250.
McDermott, J. H., Lehr, A. J., & Oxenham, A. J. (2010). Individual differences reveal the basis of consonance. Current Biology, 20(11), 1035-1041.
Papavasileiou, P., & Vatakis, A. (in preparation). Musical consonance and emotional valence: The role of timbre, musical interval, and stimulus duration.
Papavasiliou, P., & Vatakis, A. (2014). Emotional responses to musical intervals with specific acoustical properties and the effect of the induced emotions in duration perception. Procedia - Social and Behavioral Sciences, 126, 237-238.
Parncutt, R., & Hair, G. (2011). Consonance and dissonance in music theory and psychology: Disentangling dissonant dichotomies. Journal of Interdisciplinary Music Studies, 5(2), 119-166.
Sethares, W. A. (2005). Tuning, timbre, spectrum, scale (Vol. 2). London: Springer.
Tenney, J. (1988). A history of consonance and dissonance. New York: Excelsior.
Trainor, L. J., & Heinmiller, B. M. (1998). The development of evaluative responses to music: Infants prefer to listen to consonance over dissonance. Infant Behavior and Development, 21(1), 77-88.
