1346 MARATOS, MOGG, BRADLEY position of T2 in the RSVP stream, relative to the T1 position). Each of the seven lag positions corresponded to a stimulus onset asynchrony (SOA) between T1 and T2 of 257 ms (Lag 2), 385.5 ms (Lag 3), 514 ms (Lag 4), 642.5 ms (Lag 5), 771 ms (Lag 6), 1028 ms (Lag 8) and 1156.5 ms (Lag 9). The design of the experiment was such that, for each of these lag conditions, there were ten trials for every T1 T2 Trial Type (i.e., threat, positive and neutral trials). The single-target trials were the same as the double-target trials, with the exception that only one target was presented (i.e., the T1 was replaced by a distractor stimulus). Thus, the target stimulus on single-target trials was presented under the same conditions as the T2 on double-target trials (i.e., in all equivalent serial positions in the RSVP stream). Finally, to ensure that not all T1 stimuli were neutral and that not all emotional stimuli were paired with a neutral stimulus, four further trial types were included: (1) threat T1 neutral T2 (80 trials); (2) positive T1 neutral T2 (80 trials); (3) threat T1 positive T2 (40 trials); and (4) positive T1 threat T2 (40 trials). For each of these trial types, the number of trials at each lag position was balanced so that there was an equal number of trials in each lag position, as described earlier for the experimental trials. RESULTS Single-target (control) trials On single-target trials (with no T1 target), the mean percentage of trials on which both the number and type of target were correctly identified was 86%. An analysis of variance (ANOVA) of these correct responses was carried out with Face Type (threat, positive, neutral) and Serial Position (early, mid, late)2 as independent variables. This revealed only a significant main effect of face type, F(2, 38) 5.62, pB.01, h2p .23. Pair-wise Bonferroni corrected comparisons revealed poorer performance on trials with positive faces (M 82%, SD 16) compared with threat faces (M 87%, SD 13) and neutral faces (M 89%, SD 8). Of importance, the mean error rate for trials with threat targets did not significantly differ from those with neutral targets. A supplementary analysis was also carried out to compare performance accuracy for the two exemplars of neutral faces (neutral1 vs. neutral2); this analysis showed no significant results, t(19) 0.66, p .5, so the data from these two exemplars were collapsed into a single neutral face category. 2 Targets presented at serial positions 7 10, 11 14 and 15 18 formed the early, mid and late serial position levels, respectively. The data were collapsed from 12 positions into these three categories to reduce floor effects in the analyses.