How do listeners react to different urban soundscapes? An fMRI study of perception and emotion

The present study investigated the neural correlates of the perceptual and affective responses to urban sound environments using functional magnetic resonance imaging (fMRI). Sixteen participants were scanned whilst passively listening to a set of recordings made in urban spaces. In total, there were 150 recordings, each containing multiple sound sources. Soundscapes were matched in overall sound level (71 dB, A weighted), but differed in their ratings of pleasantness measured on a 5-point scale. As expected, listening to urban soundscapes evoked a significant response in a number of auditory brain regions (inferior colliculus, medial geniculate body, and auditory cortex). Those soundscapes evoking a strong emotional response (either pleasant or unpleasant) activated the amygdala, one of the main emotional centers in the brain. The perceived emotional valence of the soundscape also modulated the auditory response to the sounds. Our results confirm that the subjective metric has physiological validity, and that soundscapes with the same level can have dramatically different effects on the brain.