title: Human screams occupy a privileged niche in the communication soundscape.
abstract: Screaming is arguably one of the most relevant communication signals for survival in humans. Despite their practical relevance and their theoretical significance as innate [1] and virtually universal [2, 3] vocalizations, what makes screams a unique signal and how they are processed is not known. Here, we use acoustic analyses, psychophysical experiments, and neuroimaging to isolate those features that confer to screams their alarming nature, and we track their processing in the human brain. Using the modulation power spectrum (MPS [4, 5]), a recently developed, neurally informed characterization of sounds, we demonstrate that human screams cluster within restricted portion of the acoustic space (between ∼30 and 150 Hz modulation rates) that corresponds to a well-known perceptual attribute, roughness. In contrast to the received view that roughness is irrelevant for communication [6], our data reveal that the acoustic space occupied by the rough vocal regime is segregated from other signals, including speech, a pre-requisite to avoid false alarms in normal vocal communication. We show that roughness is present in natural alarm signals as well as in artificial alarms and that the presence of roughness in sounds boosts their detection in various tasks. Using fMRI, we show that acoustic roughness engages subcortical structures critical to rapidly appraise danger. Altogether, these data demonstrate that screams occupy a privileged acoustic niche that, being separated from other communication signals, ensures their biological and ultimately social efficiency.
authors.affiliation: Department of Clinical Neurosciences, University Hospital (HUG) and University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva, Switzerland; Department of Psychology, New York University, 6 Washington Place, New York, NY 10003, USA. Electronic address: luc.h.arnal@gmail.com.
authors.forename: Luc H
authors.initials: LH
authors.lastname: Arnal
authors.affiliation: Department of Psychology, New York University, 6 Washington Place, New York, NY 10003, USA.
authors.forename: Adeen
authors.initials: A
authors.lastname: Flinker
authors.affiliation: Department of Clinical Neurosciences, University Hospital (HUG) and University of Geneva, Rue Gabrielle-Perret-Gentil 4, 1211 Geneva, Switzerland.
authors.forename: Andreas
authors.initials: A
authors.lastname: Kleinschmidt
authors.affiliation: Department of Neuroscience, University of Geneva, Biotech Campus, 9 Chemin des Mines, 1211 Geneva, Switzerland.
authors.forename: Anne-Lise
authors.initials: AL
authors.lastname: Giraud
authors.affiliation: Department of Psychology, New York University, 6 Washington Place, New York, NY 10003, USA; Max Planck Institute for Empirical Aesthetics, Grüneburgweg 14, 60322 Frankfurt am Main, Germany. Electronic address: david.poeppel@nyu.edu.
authors.forename: David
authors.initials: D
authors.lastname: Poeppel
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D013016:Sound; D013061:Speech Acoustics; D013065:Speech Intelligibility; D013067:Speech Perception; D055815:Young Adult