Applied Neuroscience Branch
Non-Invasive Brain Stimulation Team
Air Force Research Laboratory (AFRL)
Sponsored by Northwestern University and the Air Force Center of Excellence
With increases in reliance on remotely piloted vehicles and automation, a growing number of military jobs are beginning to resemble traditional office settings and require a new, nontraditional skill set. In the Air Force, much of the mission emphasis has shifted to surveillance, intelligence, and reconnaissance (largely conducted by remotely piloted aircraft) due to the seemingly insatiable demand for such sorties. Remotely piloted aircraft operators and the supporting image analysts have long shifts (up to 12 hours a day, 6 days a week) to try to keep up with demand.
Looking for targets over a long period of time is both tedious and effortful requiring intense sustained attention/vigilance. Unfortunately, the ability to find such targets degrades over time, a phenomenon known as the vigilance decrement. Likewise, acute and chronic fatigue stress can further reduce performance. Given that misidentifying or not detecting the targets can potentially put lives at risk, investigating new methods of reducing the performance declines has been an area of interest for the Air Force.
Over the past several years, we have examined the efficacy of transcranial direct current stimulation (tDCS) to modulate attention, accelerate learning, and mitigate the effects of fatigue. We have discovered that tDCS has a large effect on target detection accuracy in a variety of vigilance tasks and this effect is repeatable and not dependent on the particular vigilance task. Specifically, tDCS extends vigilance performance by at least two fold. Likewise, we have found that small changes in the position of the anode did not significantly influence the performance outcomes. We have also found that tDCS significantly reduces the effects of fatigue on vigilance performance and that the effect lasts three times longer than caffeine. Likewise, there are beneficial effects on training, specifically for imageanalysts. Analysts receiving tDCS during training performed 25% better on their tests than analysts receiving sham tDCS. This effect has since been replicated at two different laboratories and appears to be robust and reliable. It is likely these effects may have been caused by improvements in attention. Greater attention during training often leads to improved retention following training. Taken together, tDCS has shown great promise for improving aspects of cognition that are important for existing and emerging military jobs. Determining the longevity of the effect and the effects of chronic stimulation remain critical research questions to tackle before such an intervention can be considered for deployment.
Dr. Andy McKinley is the leader of the Non-Invasive Brain Stimulation (NIBS) Team in the Cognitive Performance Optimization Section, Applied Neuroscience Branch, Warfighter Interface Division, Human Effectiveness Directorate at Wright-Patterson Air Force Base. Dr. McKinley's research focuses on developing and evaluating non-invasive brain stimulation techniques and paradigms to enhance cognitive performance in Air Force environments. Dr. McKinley is also performing basic science (6.1) to uncover the neural mechanisms of transcranial stimulation to better understand how the technology provides performance enhancement. Likewise, he is advancing the technology design through the modeling and development of new tDCS electrodes that improve safety and comfort for the user.
Dr. McKinley also has extensive experience modeling cognitive performance and human physiology under high acceleration (i.e. high -G) stress (dissertation topic) and has worked on many projects relating to human factors including display design and multisensory integration. Dr. McKinley has 45 peer-reviewed journal articles, book chapters, technical reports, and conference proceedings in these areas. He has served on multiple NATO International Panels and is currently leading an International multi-service Project Agreement.