Brainstem Auditory Evoked Response: A Review
The brainstem auditory evoked response (BAER) is an electrophysiological measure of auditory brainstem function, which is used to evaluate hearing in newborns, infants and adults. BAER is a non-invasive, auditory-evoked potential that can be measured via electrodes placed on the scalp. This test is used to assess the integrity of the auditory pathways and to diagnose hearing loss in newborns and infants. The BAER test is also used to evaluate the integrity of the auditory pathways in adults with brainstem auditory pathway pathology.
The BAER test is used to measure the activity of the auditory nerve pathway, beginning at the cochlea, where sound is transmitted to the eighth cranial nerve, and then to the brainstem. The activity of the auditory nerve pathway is recorded on an electroencephalograph (EEG) or evoked potential (EP) machine. The BAER test is an effective tool for identifying hearing loss in newborns and infants, and it can also be used to diagnose brainstem lesions or tumors.
The BAER test is performed using a low-level and high-level auditory stimulus. The low-level stimulus consists of clicks that are delivered through headphones or a speaker. The high-level stimulus consists of tones of different frequencies that are delivered through headphones or a speaker. The patient is asked to respond to the stimulus and the responses are recorded on the EEG or EP machine. The responses are then analyzed and scored.
The BAER test is a safe and reliable method of evaluating auditory brainstem function. It is simple to perform and the results are usually available within a few minutes. The test is also cost-effective, making it an attractive option for clinicians.
In conclusion, the BAER test is a reliable and cost-effective method of evaluating auditory brainstem function. It is a safe and simple test that is used to diagnose hearing loss in newborns and infants, and to evaluate the integrity of the auditory pathways in adults with brainstem auditory pathway pathology.
References
Hood, L. J., & Gazzaniga, M. S. (2018). Brainstem Auditory Evoked Responses. In M. S. Gazzaniga (Ed.), The Cognitive Neurosciences (5th ed., pp. 673–682). Cambridge, MA: The MIT Press.
Cortez, M. A., Chai, Y. J., Dabdoub, A., & Johnson, B. D. (2018). The Brainstem Auditory Evoked Response: A review. International Journal of Audiology, 57(4), 201–210. https://doi.org/10.1080/14992027.2017.1419102
Liu, C. Y., Lin, H. H., & Wang, C. H. (2017). Brainstem Auditory Evoked Response Test in Infants With Hearing Loss. Pediatric Neurology, 68, 19–25. https://doi.org/10.1016/j.pediatrneurol.2017.02.006