Hearing is an important sensory function for human beings. As children grow up, they develop an ability to communicate in an extremely complex and detailed manner. Our advanced communication is one of the defining factors of human beings. Hearing is determined by the normal functioning of the organs involved in the process of hearing. Sound waves pass through the air and enter the ear through the ear canal. These waves are reflected into the ear by the outer cartilage structure. Inside the ear, there is a membrane that responds to the sounds by vibrating. These vibrations are picked up by the inner ear and are transmitted in the form of electrical signals to the brain. In the brain, the sounds are processed.
A normal hearing test conducted on an adult or on an older child is conducted in a sound proof room with the use of headphones to play sounds to each individual ear. The subject is supposed to respond to the operator when he or she hears the sounds. This type of hearing test can easily be conducted with an individual who is capable of understanding and responding. The same cannot be applied to infants and young children. Therefore the hearing test for 2 year olds will be different when compared to the test conducted on an older person.
Parents may enroll their child in a hearing test when they find that the child does not respond to vocal stimulation. This lack of response could include occasions when the child appears not to hear his or her parent calling.
The hearing test for 2 year olds will involve the use of electrodes that are designed to pick up electrical activity in the nerves and the brain. This type of hearing test for 2 year old children can pick up the transfer of signals to the hearing center in the brain. This test can also pick up the response of the brain to these sounds. When there is proper response of the nerves and brain, the hearing test for 2 year old is said to be successful. This type of test is the same as the hearing test for infants. In both tests the parents will be allowed to accompany the child so that the child behaves as if everything is normal.
When it comes to the hearing test for 4 year old, this may be conducted in a similar way to an adult test or an infant, depending on the judgment of the doctor.