title: Perceptual Temporal Asymmetry Associated with Distinct ON and OFF Responses to Time-Varying Sounds with Rising versus Falling Intensity: A Magnetoencephalography Study.
abstract: This magnetoencephalography (MEG) study investigated evoked ON and OFF responses to ramped and damped sounds in normal-hearing human adults. Two pairs of stimuli that differed in spectral complexity were used in a passive listening task; each pair contained identical acoustical properties except for the intensity envelope. Behavioral duration judgment was conducted in separate sessions, which replicated the perceptual bias in favour of the ramped sounds and the effect of spectral complexity on perceived duration asymmetry. MEG results showed similar cortical sites for the ON and OFF responses. There was a dominant ON response with stronger phase-locking factor (PLF) in the alpha (8-14 Hz) and theta (4-8 Hz) bands for the damped sounds. In contrast, the OFF response for sounds with rising intensity was associated with stronger PLF in the gamma band (30-70 Hz). Exploratory correlation analysis showed that the OFF response in the left auditory cortex was a good predictor of the perceived temporal asymmetry for the spectrally simpler pair. The results indicate distinct asymmetry in ON and OFF responses and neural oscillation patterns associated with the dynamic intensity changes, which provides important preliminary data for future studies to examine how the auditory system develops such an asymmetry as a function of age and learning experience and whether the absence of asymmetry or abnormal ON and OFF responses can be taken as a biomarker for certain neurological conditions associated with auditory processing deficits.
authors.affiliation: Department of Speech-Language-Hearing Sciences, University of Minnesota, Minneapolis, MN 55455, USA. zhanglab@umn.edu.|Center for Neurobehavioral Development, University of Minnesota, Minneapolis, MN 55455, USA. zhanglab@umn.edu.|Speech-Language-Hearing Center, School of Foreign Languages, Shanghai Jiao Tong University, Shanghai 200240, China. zhanglab@umn.edu.
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: English Department & Institute for Language, Cognition and Brain Sciences, School of Foreign Studies, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, China. bch@mail.xjtu.edu.cn.
authors.forename: Bing
authors.initials: B
authors.lastname: Cheng
authors.affiliation: Department of Speech-Language-Hearing Sciences, University of Minnesota, Minneapolis, MN 55455, USA. koern030@umn.edu.
authors.forename: Tess K
authors.initials: TK
authors.lastname: Koerner
authors.affiliation: Department of Speech-Language-Hearing Sciences, University of Minnesota, Minneapolis, MN 55455, USA. schla001@umn.edu.
authors.forename: Robert S
authors.initials: RS
authors.lastname: Schlauch
authors.affiliation: School of Science and Engineering, Tokyo Denki University, Ishizaka, Hatoyama, Hiki-gun, Saitama, 350-0394, Japan. ktanaka@mail.dendai.ac.jp.
authors.forename: Keita
authors.initials: K
authors.lastname: Tanaka
authors.affiliation: School of Information Environment, Tokyo Denki University, 2-1200, Muzai-gakuendai, Inzai-shi, Chiba 270-1382, Japan. kawakatu@asrl.dendai.ac.jp.
authors.forename: Masaki
authors.initials: M
authors.lastname: Kawakatsu
authors.affiliation: School of Information Environment, Tokyo Denki University, 2-1200, Muzai-gakuendai, Inzai-shi, Chiba 270-1382, Japan. nemoto@sie.dendai.ac.jp.
authors.forename: Iku
authors.initials: I
authors.lastname: Nemoto
authors.affiliation: Institute for Learning and Brain Sciences, University of Washington, Seattle, Washington 98195, USA. imada@u.washington.edu.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Imada
keywords: MEG; auditory OFF response; auditory ON response; equivalent current dipole (ECD); minimum norm estimation (MNE); phase locking factor (PLF); temporal asymmetry index (TAI)