How unintentional cues can bias threat assessments during shoot/don't-shoot simulations.

OBJECTIVE: Identify whether contextual information may unintentionally alter decision-making during lethal force training. BACKGROUND: Lethal force decisions inherently involve a threat assessment, where an individual learns to identify a threat and use force commensurate to the situation. This decision is ultimately subject to numerous cognitive influences, particularly during training where artificial factors may bias decision-making. METHOD: Participants made threat assessments for tasks that presented hostile stimuli (pointing guns) and non-hostile stimuli (holding cell phones). Experiment 1 identified issues in target design by applying scoring rings as cues to targets, whereas Experiment 2 used bullet holes to assess cues due to target reuse. Experiment 3 applied these cues equally to hostile and non-hostile stimuli to prevent a predictive relationship from forming. RESULTS: Significant cueing effects were observed in both Experiments 1 and 2. For Experiment 3, response times were not impacted by the invalid cues as participants could no longer reliably use the cue to distinguish between hostile and non-hostile stimuli. CONCLUSION: Stimulus-related factors can unintentionally create predictive relationships during lethal force training. These predictive factors are problematic because they allow participants to make threat assessments during training in a way that would never be realistic in the field. APPLICATION: Modifications should be made to hostile and non-hostile targets in equal measure to avoid creating an unintentionally predictive relationship that identifies hostile targets. In practice, scoring rings and bullet holes should be added to non-hostile stimuli to better parallel hostile stimuli.

Immediate pre-learning stress enhances baseline startle response and fear acquisition in a fear-potentiated startle paradigm.

Extensive work has shown that stress time-dependently influences hippocampus-dependent learning and memory. In particular, stress that is administered immediately before learning enhances long-term memory, while stress that is temporally separated from learning impairs long-term memory. We have extended these findings by examining the impact of immediate, pre-learning stress on an amygdala-dependent fear conditioning task. One hundred and forty-one healthy participants underwent a stress (socially evaluated cold pressor test) or control manipulation immediately before completing differential fear conditioning in a fear-potentiated startle paradigm. Participants then completed extinction and extinction memory testing sessions 24 and 48 h later, respectively. Stress administered immediately before acquisition increased baseline startle responses and enhanced fear learning, as evidenced by greater fear-potentiated startle to the CS + . Although no group differences were observed during extinction training on Day 2, stressed participants exhibited evidence of impaired extinction processes on Day 3, an effect that was driven by group differences in acquisition. Importantly, stressed participants' cortisol responses to the stressor on Day 1 were positively associated with CS discrimination on Days 2 and 3. These findings suggest that stress immediately before fear conditioning strengthens fear memory formation and produces a more enduring fear memory, perhaps via corticosteroid activity. Such a paradigm could be useful for understanding factors that influence traumatic memory formation.