About five percent of the world population living with deafness various intensities. Experts from the world health organization reported that about half of these cases could have been prevented with timely diagnosis and prevention.
In a situation when people, for whatever reasons, loses his sense of hearing or has a congenital hearing problem, time usually works against him. So, in order to detect hearing loss it is important before the age of one year. Later the treatment of disorders of hearing and deafness is ineffective.
Despite great advances in the diagnosis of hearing loss, the modern high-tech sophisticated methods are not available for many professionals and, as a consequence, their patients.
So, currently, the most common way of testing of hearing acuity remains the standard audiometry. The study relies entirely on the ability of a person to click on submit or any other signal in response to audible sounds of different frequencies (typically from 250 to 8000 Hz).
And then the obvious becomes the main imperfection of the method. Such a task is not suitable for babies and young children. In addition, adults who have had a stroke, paralyzed and suffering from some mental illness will also not be able to fulfill it.
a Potential solution to this problem was invented by the experts almost by accident. More than two decades ago, scientists from the University of Oregon conducted a study involving relatives of owls common barn owl.
the Experiments had no direct relation to the study of hearing. In the process, one of the young professionals Avinash Singh Bala (Bala Avinash Singh) drew attention to an interesting feature of the birds: every time the birds hear some unexpected sound, their pupils dilate.
the Monitoring of barn owl led scientists to the idea of creating a “pupillary” auditorythe first test.Photo Of Stevie B/Wikimedia Commons.
“Remember, then we thought, what if this works for humans? In this case, we would get a great way to assess hearing in people who for whatever reason can’t respond by pressing a button, raising your hand or saying that he heard the signal,” says lead author of the new scientific work the Ball to a press release from the University.
All of the following years, the biologist was looking for ways to develop a reliable method of “pupil” diagnosis of hearing loss in humans (and in their free research time).
And finally, after numerous not very successful attempts, Bala and his colleagues proved that the eye is not just a mirror of the soul, but also a “window” into the world of sounds.
In their new promising experiment involved 31 people. The average age of volunteers was 24 years old. The study simultaneously conducted in the traditional hearing test and monitor the response of the eye.
while the volunteers looked at a point on the screen, it lost the audio signal. The sounds were reproduced with a random delay of a few seconds, to exclude the possibility that participants will be able to predict the time of occurrence of the signal.
the pupil Size was monitored for three seconds: one second before sound playback and two more after termination.
At this time, the point on the screen, which was looking for volunteers, followed by a question mark. When he appeared, participants pressed one of two buttons, making it clear, they heard the sound or not.
Stage test with a question mark was introduced for a reason. The fact that the physical force required to press the button, itself, can affect pupil size. Therefore, the participants pressed her after scientists tracked the behavior of the eyes in response to the audio signal.
the Experiment showed that the pupils of the participants expanded on average 250 milliseconds after the tone. According to the researchers, the reaction rate indicates a clear causal SVyahzee. That is, the eyes of the participants reacted to the sound.
“We found that our proposed method is as sensitive as the standard test with the push of a button,” reports the lead author of the experiment.
currently, Bala and his colleagues are collaborating with psychologists and pediatricians. Scientists intend to test the effectiveness of the developed approach on a sample involving infants and young children.
the results of the experiments published in a special edition of the Journal of the Association for Research in Otolaryngology free.
By the way, earlier authors “News.Science” (nauka.vesti.ru) told about the relationship of the gene responsible for the vision, with senile deafness and temporary blindness, permanently aggravated hearing animals. We wrote about the amazing synchronization of the movements of the eyes and eardrums.