informed that the novel sounds would be presented, and if they asked questions about their presence, they were reminded to respond only to the target tones. Target tones were 300 ms in duration and the 48 unique novel sounds ranged in duration from 100 to 400 ms (mean = 301.4 ms, S.D. = 71.8). All stimuli were presented binaurally at 75 dB SPL over TDH-49 headphones. Target (500 or 350 Hz) and response hand (right or left) for a given block were counterbalanced within subjects in each group. Further details concerning the novelty task are given elsewhere (Friedman et al., 1993).
