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Lori J. Leibold
Address:
Center for Hearing Research Boys Town National Research Hospital 555 North 30th Street Omaha, Nebraska 68131 USA
Email:
lori.leibold@boystown.org
Emily Buss
Address:
Department of Otolaryngology/Head and Neck Surgery University of North Carolina at Chapel Hill 170 Manning Drive Campus Box 7070 Chapel Hill, North Carolina 27599 USA
Email:
ebuss@med.unc.edu
Lauren Calandruccio
Address:
Department of Psychological Sciences Case Western Reserve University Cleveland Hearing and Speech Center 11635 Euclid Avenue Cleveland, Ohio 44106 USA
Email:
lauren.calandruccio@case.edu
https://doi.org/10.1121/AT.2019.15.1.38
Too Young for the Cocktail Party?
One reason why children and cocktail parties do not mix.
There are many reasons why children and cocktail parties do not mix. One less obvious reason is that children struggle to hear and understand speech when mul- tiple people are talking at the same time. Cherry (1953) was not likely thinking about children when he coined the “cocktail party problem” over 60 years ago, referring to the speech perception difficulties individuals often face in social en- vironments with multiple sources of competing sound. Subsequent research has largely focused on trying to understand how adults recognize what one person is saying when other people are talking at the same time (reviewed by Bronkhorst, 2000; McDermott, 2009). However, modern classrooms pose many of the same challenges as a cocktail party, with multiple simultaneous talkers and dynamic listening conditions (Brill et al., 2018). In contrast to the cocktail party, however, failure to recognize speech in a classroom can have important consequences for a child’s educational achievement and social development. These concerns have prompted several laboratories, including ours, to study development of the ability to recognize speech in multisource backgrounds. This article summarizes findings from the smaller number of studies that have examined the cocktail party prob- lem in children, providing evidence that children are at an even greater disadvan- tage than adults in complex acoustic environments that contain multiple sources of competing sounds.
For much of the school day, children are tasked with listening to their teacher in the context of sounds produced by a range of different sound sources in the class- room. Under these conditions, we would call the teacher’s voice the target and the background sounds would be the maskers. All sounds in the environment, in- cluding the target and the maskers, combine in the air before reaching the child’s ears. This combination of acoustic waveforms is often referred to as an auditory scene. An example of an auditory scene is illustrated in Figure 1, where sounds in- clude the relatively steady noise produced by a projector as well as more dynamic sounds, such as speech produced by classmates who are talking at the same time as their teacher. To hear and understand the teacher, the spectral and temporal characteristics of this mixture of incoming sounds must be accurately represented by the outer ear, middle ear, cochlea, and auditory nerve. This processing is often referred to as peripheral encoding. Auditory perception is critically dependent on the peripheral encoding of sound and the fidelity with which this information is transmitted to the brain. Processing within the central auditory system is then needed to identify and group the acoustic waveforms that were generated by the teacher from those that were generated by the other sources (sound source segre- gation) and then allocate attention to the auditory “object” corresponding to the teacher’s voice while discounting competing sounds (selective auditory attention). Auditory scene analysis also relies on cognitive processes, such as memory, as well as listening experience and linguistic knowledge. Collectively, these processes are often referred to as auditory scene analysis (e.g., Bregman, 1990; Darwin and Hukin, 1999).
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volume 15, issue 1 | Spring 2019 | Acoustics Today | 37