Original Research ARTICLE
Preliminary evidence of pre-attentive distinctions of frequency-modulated tones that convey affect
- 1 Neuropsychiatry Section, Department of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
- 2 Program in Cognitive Neuroscience and Schizophrenia, Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, USA
- 3 Program in Cognitive Neuroscience, The City College of the City University of New York, New York, NY, USA
- 4 Department of Psychiatry, NYU School of Medicine, New York, NY, USA
Recognizing emotion is an evolutionary imperative. An early stage of auditory scene analysis involves the perceptual grouping of acoustic features, which can be based on both temporal coincidence and spectral features such as perceived pitch. Perceived pitch, or fundamental frequency (F0), is an especially salient cue for differentiating affective intent through speech intonation (prosody). We hypothesized that: (1) simple frequency-modulated tone abstractions, based on the parameters of actual prosodic stimuli, would be reliably classified as representing differing emotional categories; and (2) that such differences would yield significant mismatch negativities (MMNs) – an index of pre-attentive deviance detection within the auditory environment. We constructed a set of FM tones that approximated the F0 mean and variation of reliably recognized happy and neutral prosodic stimuli. These stimuli were presented to 13 subjects using a passive listening oddball paradigm. We additionally included stimuli with no frequency modulation (FM) and FM tones with identical carrier frequencies but differing modulation depths as control conditions. Following electrophysiological recording, subjects were asked to identify the sounds they heard as happy, sad, angry, or neutral. We observed that FM tones abstracted from happy and no-expression speech stimuli elicited MMNs. Post hoc behavioral testing revealed that subjects reliably identified the FM tones in a consistent manner. Finally, we also observed that FM tones and no-FM tones elicited equivalent MMNs. MMNs to FM tones that differentiate affect suggests that these abstractions may be sufficient to characterize prosodic distinctions, and that these distinctions can be represented in pre-attentive auditory sensory memory.
Keywords: mismatch negativity, MMN, frequency modulation, auditory, cortex, emotion, speech
Citation: Leitman DI, Sehatpour P, Garidis C, Gomez-Ramirez M and Javitt DC (2011) Preliminary evidence of pre-attentive distinctions of frequency-modulated tones that convey affect. Front. Hum. Neurosci. 5:96. doi: 10.3389/fnhum.2011.00096
Received: 25 March 2011;
Accepted: 19 August 2011;
Published online: 03 October 2011.
Edited by:Hans-Jochen Heinze, University of Magdeburg, Germany
Reviewed by:Micah M. Murray, Université de Lausanne, Switzerland
Claude Alain, Rotman Research Institute, Canada
Copyright: © 2011 Leitman, Sehatpour, Garidis, Gomez-Ramirez and Javitt. This is an open-access article subject to a non-exclusive license between the authors and Frontiers Media SA, which permits use, distribution and reproduction in other forums, provided the original authors and source are credited and other Frontiers conditions are complied with.
*Correspondence: David I. Leitman, Neuropsychiatry Program, Brain Behavior Laboratory, Department of Psychiatry, University of Pennsylvania, Gates Pavilion 10th floor, 3400 Spruce Street, Philadelphia, PA 19104-4283, USA. e-mail: email@example.com