Poster B87, Sunday, March 25, 8:00-10:00 am, Exhibit Hall C
The subtle impact of oscillatory phase on auditory detection
Yue Sun1, Oded Ghitza1,2, David Poeppel1,3; 1Max Planck Institute for Empirical Aesthetics, Frankfurt am Main, Germany, 2Boston University, Boston, USA, 3New York University, New York, USA
Acoustic rhythms are a fundamental feature in our acoustic environment, including in speech and music (Ding et al., 2017). It has been proposed that auditory processing profits from the entrainment of cortical neural oscillations to the rhythmicity of the acoustic input, which aligns optimal oscillatory phase with critical auditory events (Schroeder & Lakatos., 2009). However, to what extent oscillatory phase influences the efficiency of auditory processing is still a subject of controversy (VanRullen, 2014). Here we examined the robustness of phase-modulated decoding, using an auditory detection paradigm adapted from a recent study (Hickok et al., 2015). Participants were asked to detect a 1-kHz tone embedded in background noise following an acoustic entrainment signal modulated at 3 Hz. The target tone was presented at various positions aligned with different phases of the preceding entrainment. While the original study showed that the detectability of the tone, presented at a near-threshold intensity, was strongly modulated at the frequency of preceding entrainment and consistently aligned with its phase, a similar effect was found in our study only when the tone was presented 6 dB above participants’ individual thresholds. Meanwhile, when the tone was presented at a near-threshold intensity, the detection accuracy was no longer modulated at the frequency of the entrainment signal but at a lower frequency, around 1.5 Hz. Our findings demonstrate the subtlety of phase-modulated detection in audition and its sensitivity to experimental protocol and task difficulty.
Topic Area: PERCEPTION & ACTION: Audition