Normative Study of Brain Stem Auditory Evoked Potentials in Young Adults

ABSTRACT Brain Stem Auditory Evoked Potentials (BAEP) are potentials recorded from ear and vertex in response to brief auditory stimulation to asses conduction through the auditory pathway upto the level of midbrain. BAEP comprises of five or more waves within ten milliseconds of the stimulus and three interpeak latencies. Each individual wave and interpeak latencies provides information about an area of auditory pathway starting with cochlear nerve to the level of inferior colliculi. Recently these potentials have been widely studied in audiology, neurology, neonatology and anaesthesiology. These potentials tend to vary with various ethnic groups. Since India has a widely diverse ethnic population, this study was undertaken to prepare normative data pertaining to local population and normalize the results with variables such as gender and anthropometric measures like head size which could have an effect on these recordings. In this randomized study, 100 normal subjects (50 males and 50 females) were selected. BAEP was recorded using EMG RMS PK II machine. Head measurements were taken with a measuring tape. The results were analyzed by descriptive methods. Males showed greater head measures and greater wave and interpeak latencies than female subjects with a significant p value of less than 0.001. All wave and interpeak latencies were greater in males than in females which could be because of bigger head size measurements in males