The hearing test known as the brainstem auditory evoked response (BAER) detects electrical activity in the animal's ear and hearing pathways in the brain in much the same way that an antenna detects radio signals or an EKG detects electrical activity of the animal's heart. The BAER is a non-invasive test that our veterinary pathology specialists use to detect inherited or acquired deafness. It is performed by placing very small electrodes under the skin of the scalp and small foam insert headphones into the ears. A computer produces noises that are directed into the ear and then the hearing response is collected by the computer resulting in a determination of hearing. The test usually takes 10-15 minutes and sedation or anesthesia is rarely needed.