Brainstem Evoked Response Audiometry

BERA (Brainstem Evoked Response Audiometry) is an electro-physiological test procedure to measure the responses of brain waves stimulated by a clicking sound to identify the central auditory or hearing pathways of the brainstem.

The brainstem evoked response audiometry (BERA) aids is an objective test in evaluating the hearing threshold. It also helps in diagnosing retrocochlear lesions in children with suspected hearing loss or pathological speech development.

This procedure involves the study of electrical activities and responses of the brain to the sound and is beneficial for measuring the hearing ability of both adults and children.

The ear consists of three different parts including the outer, middle and inner ear. The outer ear involves the visible part called auricle or pinna and external auditory canal. The middle ear is formed by the eardrum or tympanic membrane and tympanic cavity containing three small bones named hammer, anvil and stirrup or collectively known as ossicles. The inner ear contains cochlea and vestibular system or organ of balance. The sound waves reach the outer ear and vibrate the eardrum. The vibration gets transmitted to middle ear and from there to inner ear. In the inner ear an important structure called cochlea converts the sound waves into electrical signals and sends to the brain. The brain decodes and interprets these signals and perceive as music, message, loud or quiet speech.

In BERA electrodes are placed to the skin of the head and behind the ear which measure the receiving sound waves in the form of electrical signals capacity of the brain. A special head phone also can be used through which clicking sounds can be sent to the inner ear. Any impairment in the transmission of the signals indicates a problem associated with hearing.

The advantages of the BERA (Brainstem Evoked Response Audiometry) test include early diagnosis of hearing impairment, identification of causes of hearing impairment.