Percentage of rats that showed any seizure behavior summed across all noise intensities (100, 105, and 110 dB) for females and males (A and C). Running fits followed by clonus for females and males (B and D). Percentage of rats that showed clonus seizure at 100, 105, and 110 dB noise intensity. n = 9 for controls and 8 for PCB-exposed group for both males and females. F, females, M, males. * indicates that the 6 mg/kg PCB exposure group significantly differed from the control group (P < .05).