- Explaining the high voice superiority effect in polyphonic music: Evidence from cortical evoked potentials and peripheral auditory models.
- Trainor LJ1, Marie C2, Bruce IC3, Bidelman GM4.Author information 1Department of Psychology, Neuroscience & Behaviour, McMaster University, Hamilton, ON, Canada; McMaster Institute for Music and the Mind, Hamilton, ON, Canada; Rotman Research Institute, Baycrest Centre, Toronto, ON, Canada. Electronic address: email@example.comDepartment of Psychology, Neuroscience & Behaviour, McMaster University, Hamilton, ON, Canada; McMaster Institute for Music and the Mind, Hamilton, ON, Canada.3McMaster Institute for Music and the Mind, Hamilton, ON, Canada; Department of Electrical and Computer Engineering, McMaster University, Hamilton, ON, Canada.4Institute for Intelligent Systems, University of Memphis, Memphis, TN, USA; School of Communication Sciences & Disorders, University of Memphis, Memphis, TN, USA.AbstractNatural auditory environments contain multiple simultaneously-sounding objects and the auditory system must parse the incoming complex sound wave they collectively create into parts that represent each of these individual objects. Music often similarly requires processing of more than one voice or stream at the same time, and behavioral studies demonstrate that human listeners show a systematic perceptual bias in processing the highest voice in multi-voiced music. Here, we review studies utilizing event-related brain potentials (ERPs), which support the notions that (1) separate memory traces are formed for two simultaneous voices (even without conscious awareness) in auditory cortex and (2) adults show more robust encoding (i.e., larger ERP responses) to deviant pitches in the higher than in the lower voice, indicating better encoding of the former. Furthermore, infants also show this high-voice superiority effect, suggesting that the perceptual dominance observed across studies might result from neurophysiological characteristics of the peripheral auditory system. Although musically untrained adults show smaller responses in general than musically trained adults, both groups similarly show a more robust cortical representation of the higher than of the lower voice. Finally, years of experience playing a bass-range instrument reduces but does not reverse the high voice superiority effect, indicating that although it can be modified, it is not highly neuroplastic. Results of new modeling experiments examined the possibility that characteristics of middle-ear filtering and cochlear dynamics (e.g., suppression) reflected in auditory nerve firing patterns might account for the higher-voice superiority effect. Simulations show that both place and temporal AN coding schemes well-predict a high-voice superiority across a wide range of interval spacings and registers. Collectively, we infer an innate, peripheral origin for the higher-voice superiority observed in human ERP and psychophysical music listening studies. This article is part of a Special Issue entitled <Music: A window into the hearing brain>.
- Hearing research.Hear Res.2014 Feb;308:60-70. doi: 10.1016/j.heares.2013.07.014. Epub 2013 Aug 3.
- Natural auditory environments contain multiple simultaneously-sounding objects and the auditory system must parse the incoming complex sound wave they collectively create into parts that represent each of these individual objects. Music often similarly requires processing of more than one voice or s
- PMID 23916754
- National-level differences in the adoption of environmental health technologies: a cross-border comparison from Benin and Togo.
- Wendland KJ, Pattanayak SK, Sills EO.Author information Department of Conservation Social Sciences, University of Idaho, Moscow, ID 83844, USA, Stanford School of Public Policy; Nicholas School of the Environment; Global Health Institute, Duke University, Durham, NC 27708, USA and Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, NC 27695-8008, USA.AbstractEnvironmental health problems such as malaria, respiratory infections, diarrhoea and malnutrition pose very high burdens on the poor rural people in much of the tropics. Recent research on key interventions-the adoption and use of relatively cheap and effective environmental health technologies-has focused primarily on the influence of demand-side household-level drivers. Relatively few studies of the promotion and use of these technologies have considered the role of contextual factors such as governance, the enabling environment and national policies because of the challenges of cross-country comparisons. We exploit a natural experimental setting by comparing household adoption across the Benin-Togo national border that splits the Tamberma Valley in West Africa. Households across the border share the same culture, ethnicity, weather, physiographic features, livelihoods and infrastructure; however, they are located in countries at virtually opposite ends of the institutional spectrum of democratic elections, voice and accountability, effective governance and corruption. Binary choice models and rigorous non-parametric matching estimators confirm that households in Benin are more likely than households in Togo to plant soybeans, build improved cookstoves and purchase mosquito nets, ceteris paribus. Although we cannot identify the exact mechanism for the large and significant national-level differences in technology adoption, our findings suggest that contextual institutional factors can be more important than household characteristics for technology adoption.
- Health policy and planning.Health Policy Plan.2014 Jan 15. [Epub ahead of print]
- Environmental health problems such as malaria, respiratory infections, diarrhoea and malnutrition pose very high burdens on the poor rural people in much of the tropics. Recent research on key interventions-the adoption and use of relatively cheap and effective environmental health technologies-has
- PMID 24436179