title: Characterizing perceptual properties of a binaurally modulated stimulus.
abstract: The majority of everyday listening situations involve a complex mixture of multiple sound sources. Assuming a spectro-temporally sparse target signal, e.g., speech, the binaural cues in these complex listening environments do not simply result from a single sound source, but are often rapidly switching between the most dominant sources at any given moment. To investigate the perception of rapidly switching interaural time difference (ITD) cues, a noise stimulus that periodically alternates between two different values of ITD was created. This stimulus appears to evoke a purely binaural percept of modulation, which is the focus of the studies presented here. Results indicate that listeners can reliably discriminate this ITD-switching stimulus from a stimulus composed of stationary ITD cues. Frequency discrimination of this ITD-switching stimulus was tested in a separate experiment, which showed that listeners are generally able to discriminate a 50% change in modulation frequency for reference rates below 16 Hz. The final study investigated if modulation masking exists between the monaural and binaural auditory pathways. Although a statistically significant increase in modulation detection thresholds was observed when both types of modulations were presented together, the increase was relatively small, indicating only a weak interaction.
authors.affiliation: Acoustics Group, Forschungszentrum Neurosensorik, Cluster of Excellence Hearing4all, Universität Oldenburg, 26111 Oldenburg, Germany.
authors.forename: Darrin K
authors.initials: DK
authors.lastname: Reed
authors.affiliation: Acoustics Group, Forschungszentrum Neurosensorik, Cluster of Excellence Hearing4all, Universität Oldenburg, 26111 Oldenburg, Germany.
authors.forename: Steven
authors.initials: S
authors.lastname: van de Par