WHAT IS HEARING:
The process of collecting the sound waves in the atmosphere from our ear to the perception of character and meaning in the centers of the brain is called hearing.

WHAT IS SOUND:
Sound energy is a vibration. It is a mechanical vibration wave emitted in a medium composed of matter. According to a clinician, sound is the stimulus of hearing.

WHAT IS SOUND FREQUENCY:
The number of vibrations that occur in one second is called the sound frequency. The sound frequency unit is Hertz (Hz). As the frequency increases, the sound becomes high (thinner). Low-frequency sounds generate pes (thick) sounds. The human ear can hear sounds between 16 and 20000 Hz. The subsonic sounds with less than 16 vibrations per second and the ones over 20000 are called ultrasonic sounds.

WHAT IS THE VIOLENCE OF VOICE:
The height of the sound heard by the ear is called the intensity of the sound. The unit of violence is decibel (dB). Decibel is the smallest volume of sound that the human ear can hear.
Whisper sound 30 dB
Speech sound 40-60 dB
Shouting sound 80-90 dB
Flight departure 120-140 dB
Rifle explosion (close distance) 130 dB

WHAT IS ODYOMETRIC EXAMINATION:
The evaluation of hearing and evaluation of hearing functions are called audiometric examination. The devices used in these measurements are called audiometers.

Hearing occurs in two ways;
1- By air (air conduction)
2- Bone conduction
In a normal hearing ear, airborne hearing is more than two times higher than bone without hearing.

HEARING LOSSES KEY TYPE:
Hearing losses are divided into three:
1- Conductive hearing loss: There is a pathology in the transmission of the sound to the inner ear. This may be due to a lesion in the outer and middle ear.
2- Sensorianeural type of hearing loss: hearing loss due to any disturbance in the inner ear or in the 8th nerve (hearing and balance nerve) transmission.
3- Mixed hearing loss: It is both conduction and sensorianeural hearing loss.

HEARING LOSS RISES WHAT ARE:
0-20 dB hearing loss, Very mild hearing loss
20-40 dB hearing loss, Mild hearing loss
40-60 dB hearing loss, Moderate hearing loss
60-80 dB hearing loss, Significant hearing loss
80-100 dB hearing loss, Advanced hearing loss
Hearing loss near 100 dB and above Total

WHAT ARE ODYOMETRIC EXAMINATION METHODS:
1- Tonal Audiometry:

A-Tonal Threshold Audiometry: A subjective method that detects hearing threshold by giving pure tone sounds.
B- Supralimeter Audiometry: Investigates hearing disorders in the hearing area between the minimal equalization threshold and the maximal hearing threshold.

2- Vocal Audiometry (speech audiometry): Audiometric evaluation using human voice as a sound stimulus is called speech audiometry.

3- Lens Audiometry:
A- Impedance audiometry
B- Electroencephalographic Audiometry (ERA)
C- Electrocoquilization (ECochG)
D- Brainstem evoked response audiometry (BERA)

4- Children's Audiometry (Infantile Audiometry):

WHAT IS RECRUITMENT:
It means the intolerance of the person to the sound heights.

WHAT IS RECRUITMENT AVAILABLE IN THE HEARING LOSSS:
In the case of cochlear hearing loss, the hearing area becomes narrower and there is a recruitment.

WHEN BABY IS HEARING HEADS:
Before the birth of the mother's abdomen, the auditory organ begins to function.

WHAT IS EMPEDANCE ODYOMETRY:
Middle ear, 8th nerve (N. Statoacusticus), 7th Nerve (N. Facialis) and brainstem hearing paths that provide information about, the patient does not require a prerequisite to be co-operative in the baby and children easily can show an objective audiometry method.

WHAT IS TIMPANOMETRY:
The middle ear elasticity is measured according to the pressure change in the external ear canal.

WHAT MEASURES WITH ACOUSTIC EMPEDANSMETER:
Middle ear pressure
Flexibility of middle ear
Air pressure changes in the external ear canal
Whether there is an acoustic reflex
Acoustic reflex thresholds
Acoustic reflex adaptations
Eustachian tube function
Separation of Tensor's tympani and stapes muscles separately
The effects of middle ear air pressure changes on the transmission of sound are measured.

WHAT IS ACOUSTIC REFLEX?
It is the response of the stapes muscle in the middle ear to acoustic stimuli. Acoustic reflex is taken in both ears, which should be warned if the ear is stimulated.

WHAT IS IPSILATERAL AND CONDUCTIVE REFLEX?
An ipsilateral reflex is used to measure the reflex in one ear and to give the stimulus to one ear and to measure the reflex in the opposite ear.

WHAT IS THE CLINICAL IMPORTANCE OF THE TIMPANOMETRY:
It shows us the variability of the commonality system. For example; presence of fluid in the middle ear (SOM), disconnection or fixation in the ossicular chain, eustachian tube dysfunction and otitis media.

WHEN SHOULD ACOUSTIC REFLEX
Middle ear pathology in the measured ear
7. Nerve (N.facialis) pathology
Moderate conduction hearing loss
Extremely cochlear hearing loss
8. Nervous (N. Statoacusticus) pathology
Disturbance in the brain stem acoustic reflex tract
Normal tympanogram in one person, normal impedance measurements, presence of bilateral acoustic reflex shows NORMAL HEARING
Although middle ear pressure is normal, the absence of acoustic reflex suggests HEARING LOSS.
In practice, acoustic reflex is the most used area in infants. A zero-year-old baby has a normal tympanogram and normal middle ear pressure, but if there is no acoustic reflex, this child has a PROBLEM OF HEARING. These tests are very important for early detection of hearing loss in infants.

WHAT IS THE INDICATIONS OF HEARING AID IN CHILDREN:
In children with hearing loss, children should be given the chance of hearing if medicine or surgical treatment is not possible.
Normal hearing threshold 0-20 dB is accepted. If the child has hearing loss above 20 dB, the child's speech, understanding and learning ability will be adversely affected. In this case, the hearing aid indication for children over 21 dB has been started.

Many studies have shown that mild hearing loss in children with middle ear problems for a long time affects the intellectual development of children. Normal developmental IQ = 104.5 was found in children and IQ = 92.4 in children with mild hearing loss. In addition, in children with mild hearing loss, articulation deficiency was observed. In such a case, the necessity of using hearing aids is indisputable.

WHEN DOES CHILDREN LEARN TO LEARN SPEAKING:
Children begin to learn to speak in the first months of life. Babbling and Lalling, which are the cornerstones of the speech, have the condition of having a normal hearing so that they can pass the stages. For this reason, amplification (normalization of hearing with the device) is necessary to the child as soon as possible.

WHAT IS THE CHILDREN?
This age; It is 3.5-4 years old. If there are no children until three and a half - four years of age, the chances of success in education decrease after this age. Until this age, the sensory, psychomotor, intellectual development must be completed.
Misconceptions such as the use of hearing aids after 6-7 years of age among many physicians are common. This extremely flawed application is an erroneous orientation.

EACH HEARING LOSS ALLOWED HEARING EQUIPMENT:
No, the hearing threshold of the patient is determined before selecting the hearing aid. The sound gain of each hearing aid is different. According to the degree of hearing loss, which hearing aid is suitable is determined after some tests. Control by computer. A hearing aid that is not properly selected will also destroy the existing hearing. Therefore, device selection and adaptation should be done in qualified hands. For example; If you do not give appropriate glasses to a patient with visual impairment, the patient's vision will be impaired. Hearing aids should also be selected within this principle.

CHILDREN WITH HEARING LOSS WHAT DOES THE TIME BEEN DONE?
For example, an average of 70 dB hearing loss and medical and surgical treatment is not possible for a child, 3.5-4 years of age (if the hearing aid is applied) lives as a normal person. If the same child is not amplified, he will continue his life as deaf-mute.

WHAT ARE THE REFLEXES WHICH COME TO THE VOICE WARNING IN CHILDREN WITH NORMAL HEARING

A-ELEMENT REFLEXS
a- (APR) Auropalpepral Reflex: Closure of the eyes against sounds in infants
b-Moro Reflex: Bounce reaction against sounds
c-Respiratory arrest or deepening of inspiration

B-ORIENTATION REACTION:
Turn right into sound

C-WAKE REACTION:
Sleeping child awakening

D-ATTITUDE CHANGE REACTION:
Agitating child calm or crying of calm child

RISK GROUP BABIES FOR HEARING LOSS
Patients with a history of hereditary hearing loss
Intrauterine infections such as rubella

ENT anomalies
Babies weighing less than 1500 g
Increased neurotoxic level of bilirubin
Hypoxia during labor.