Proposing a Low-Cost, Transportable Horizontal Binaural Test Using Headphones

Binaural hearing plays a significant role in auditory perception, spatial awareness, and sound source differentiation. Studies have linked cognitive decline, traumatic brain injuries, and neurodegenerative disease with decline in binaural performance, and quantification thereof may provide key information related to early onset of such diseases. Current horizontal binaural tests require multiple external speakers and an anechoic chamber, preventing broad clinical deployment, especially in remote communities. Furthermore, they use design parameters that differ widely. We hereby aim to develop a portable, easy-to-perform binaural hearing performance test, as well as identifying the ideal design parameters used in current literature, including audio prompt type, frequency, duration, and modality (speaker vs. headphone). Results indicate that a voice-form audio, with a sampling frequency of 1 kHz combined with a 4-second duration yields the best outcomes. Moreover, comparisons between speaker modality tests and our proposed headphone modality test using a Head Related Transfer Function (HRTF) reveal a high level of agreement between performances. Notably, the proposed headphone test mitigates sources of bias such as informed guessing due to visual cues, memorization of source locations, and movement of the head during tests. The findings establish the potential of a low-cost, easily accessible binaural performance test applicable across diverse settings. This research contributes insights into the design and implementation of binaural tests, with implications for fields such as audiology and neuroscience.