Optimizing How Scientists Test Hearing Accuracy
Because acoustic testing can be incredibly time-consuming and exhausting for human participants, identifying a methodology that yields accurate data in the shortest amount of time is highly valuable for auditory science. Mark Stellmack, faculty, and collaborators sought to do just that.
In a recent article published in the Journal of the Acoustical Society of America, entitled “Comparison among four psychophysical procedures used to assess sound localization,” Stellmack and collaborators sought to evaluate and compare the efficiency and reliability of four different psychophysical testing methods used by researchers to measure how accurately humans can identify where a sound is coming from in space (i.e., sound localization). They tested the absolute localization task, a baseline method where a sound is played from a speaker and the participant points directly to where they perceive it to be, and three alternative forced-choice variations, where participants listened to sequential sounds to discern a difference or identify a target direction based on strict structural options (e.g., indicating whether a second sound was to the left or right of the first).
Their findings showed that the absolute localization task was far more efficient than forced-choice tests, requiring fewer trial repetitions to establish an accurate baseline measure of sound localization. In comparison, while forced-choice measurements took longer to set a baseline, they demonstrated slightly higher sensitivity in detecting faint changes in spatial awareness.
This study from Stellmack and collaborators importantly maps a logistical trade-off for auditory researchers, providing a practical guide for design choices in hearing research. By establishing the strengths and time constraints of each method, audiologists and neuroscientists can optimize their testing protocols, enabling more efficient diagnostic testing for individuals with typical hearing, hearing loss, or spatial processing difficulties.
Mark Stellmack, PhD, associate teaching professor in the Department of Psychology at the University of Minnesota.
