SYDNEY, March 2 (Xinhua) -- Australian researchers on Saturday said they have discovered a way to assess human hearing ability by tracking heart rates, pointing to better analysis of communication and language development.
The researchers from the Bionics Institute medical research facility in Victorian state capital Melbourne measured heart rate with a brain imaging method called functional near-infrared spectroscopy, which records the brain's response to sounds and cardiac information such as heart rate, according to a statement on Saturday.
They were able to confirm that sound levels "directly affect heart rate." They played a range of sounds with different volumes and monitored the participant's cardiac response, with the results showing that heart rate was "directly affected by sound levels", according to the institute.
When lower level sounds were played, a significantly lowered heart rate was recorded; for higher level sounds, an increased heart rate occurred, the researchers found.
The objective methods of measuring hearing are crucial for babies and other people who are unable to communicate what they hear to their audiologist, said Dr Mehrnaz Shoushtarian, the lead author on the latest findings published in scientific journal PLOS One.
Early detection of hearing loss is vital for babies born with a hearing impairment, according to the institute. Identifying and treating hearing loss early is "imperative for good language development, with life-long consequences for social, educational and employment opportunities, and quality of life," it said.
The effect of sounds on heart rate is a vital finding that contributes toward the development of a novel objective hearing assessment system which combines heart rate information with brain responses, to enhance the accuracy and effectiveness of hearing assessment in infants, according to the researchers.