Table 1.
Summary of group membership (left) and illustration of the flow of participants through the study (right).
Fig 1.
Note: A: Flanker task—participant must respond with a key press to indicate the direction of the central arrow. B: Shoot/don’t-shoot task—participant must respond with a key press (left/right) to ’shoot’ if the person in the image is holding a weapon. The image on the right is just illustrative—real pictures were used for the experimental task. C: Training task—participant indicates whether there is a weapon present in any of the images using a key press. The images shown are illustrative, Sykes-McQueen threat assessment targets were used in the real task. The red distractor slows response times and has to be inhibited. D: Active control task—No distractor is present but the rest of the task is identical to the training task.
Fig 2.
Illustration of signal detection metrics.
Note: A: The four possible combinations of signals (presence or absence of a threat) and responses (shoot or don’t shoot). B-C: D-prime and beta in relation to various distributions of signal (weapon present or absent) and noise. The greyed portion of the figure represents trials where a response was made. In panel B, the participant has a large d-prime value, indicating they were able to perceive a clear difference between the signal and the noise. Beta value is shifted right indicating a conservative response strategy (more ’misses’ but very few ’false alarms’). In panel C, d-prime is smaller showing that sensitivity is reduced, but the response strategy is still conservative, so the participant still has few `false alarms’, but a lot more ’misses’. In panel D, d-prime is again large, but this time the response bias is more liberal so there are many more ’false alarms’ but few ’misses’.
Fig 3.
The figure shows a schematic representation of the flow of participants through the trial.
Fig 4.
Plot showing improvement of training performance over time (means and SDs) with corresponding reduction in reaction times (inset).
Table 2.
ANOVA results for manipulation check.
Fig 5.
Box and whisker plots with overlaid data points for performance on the flanker test.
Note: A smaller RT difference shows that the distractors were having a reduced effect, i.e., better inhibition. **p < .01.
Fig 6.
Box and whisker plots with overlaid data points for performance on the shoot/don’t-shoot (SDS) test.
Table 3.
Correlation coefficients (Spearman’s Rho) for the relationships between ‘training gain’ and improvement on the transfer tests.