All participants had normal or corrected-to-normal vision. Hearing acuity was assessed using standard audiometric procedures, requiring all participants to have an ear difference of less than 10 dB and a hearing loss no greater than 25 dB at 500, 1000, or 2000 Hz. The ethnic composition in both groups was representative for the New York region, with an approximately equal number of participants in each racial category (patients vs. controls: White 8/9, Black 6/5, Asian 1/1, Native-American 1/1, more than one race 1/2, unknown 3/2). Five participants in each group had also been included in a different working memory ERP study (Kayser et al., 2006). The experimental protocol had been approved by the institutional review board and was undertaken with the understanding and written consent of each participant.
