Speaker: Kristina DeRoy Milvae, Au.D., Ph.D., CCC-A

Title: Unexpected listening effort demands from asymmetric hearing

Abstract: Listening in complex acoustic environments is difficult and effortful.  Binaural hearing leads to improved speech understanding in these environments, but improvement is limited in listeners with bilateral cochlear implants.  Ear asymmetry may also play a role in limiting binaural hearing benefits in this population.  Additionally, the binaural benefits to listening effort are not yet clear.  A simplification of a complex acoustic environment is a dichotic listening paradigm, with target and interfering speech presented to separate ears.  In a series of experiments, the spectral resolution of the signals at the two ears was manipulated to examine how target and interfering speech clarity impacts performance and listening effort (indexed via pupillometry) in cochlear-implant simulations.  The impact of functional asymmetry was also examined in listeners with bilateral cochlear implants.  Asymmetries in spectral resolution affected performance; attending to a good ear and ignoring a poor ear increased speech understanding in comparison to the reverse.  Spectral resolution affected listening effort in unexpected ways; the benefit from a clearer target was outweighed by the effort required to ignore a clearer interferer.  A good ear is effortful to ignore.