Comparison of source localization for the P30m, P50m, and N100m peaks

Introduction N100m is the most prominent peak of the auditory evoked magnetic field (AEF) for tone burst stimulus and has been termed the long latency component. The source of the N100m is considered to be located in the primary auditory cortices along the bilateral superior temporal planes [1]. However, recent studies have suggested a possible contribution of the higher functional areas to N100m generation [2]. P50m is a deflection occurring before N100m in the AEF for tone burst stimulus. P50m is often called the middle latency component of the AEF. P30m is also called the middle latency component of the AEF, and is best elicited with different stimulus procedures such as clicks [3-5]. Both P30m and P50m have smaller amplitudes than N100m. These peaks are believed to originate in or near the primary auditory cortex [3,5-8], and previous magnetoencephalography (MEG) studies suggested that their sources are located more anterior to the N100m source [4-7]. However, these studies hav