Investigation of police decision making using combined EEG and virtual reality methods

  • Nicholas Andrew Alexander

Student thesis: Doctoral ThesisDoctor of Philosophy


Police officers in the UK are granted additional powers to allow them to protect life and property crime. Of these powers, the sanction to use stopping, potentially lethal, force given to Authorised Firearms Officers (AFO) is arguably the most salient. Each decision made by an AFO to discharge their firearm or not has great impact and so it is important we research the cognitive processes that lead to such a decision.One challenge of researching these cognitive processes is eliciting ecologically valid behaviour while maintaining internal validity. We approached this challenge by developing combined electroencephalography (EEG) and virtual reality research methods. Using these methods, we produced scenarios that reflected features of AFO training. First, we tested simple versions of the scenarios on a novice population. Following this, we increased the complexity of the scenarios and collected data from both AFOs and novices.We found that participants were fastest when responding to threatening scenarios. Further, AFOs had consistently faster response times than novices. In line with similar ‘Go/No-Go’ paradigms, we found greater increases in pre-response frontal-midline theta when participants did not shoot versus when they did. Comparisons of EEG between AFOs and novices revealed greater pre-response increases in frontal-midline theta and central delta when they equipped a firearm. Greater differences in delta activity were also observed between different levels of threat in the AFO group.Together, these findings suggest that differences in performance between experts and novices may be due to their greater attention towards threat. Further investigation of expert decision making should build on our use of naturalistic stimuli and expert participants to ensure that findings are ecologically valid.With increasing accessibility of modern game engines and virtual reality technology, this approach will be beneficial to researchers in many fields where ecological validity is required.
Date of Award2020
Original languageEnglish
SupervisorKlaus Kessler (Supervisor) & Matthew J. Brookes (Supervisor)


  • electroencephalography (EEG)
  • expertise
  • shoot/don’t-shoot
  • head-mounted display;
  • naturalistic imaging.

Cite this