title: Field assessment and enhancement of cognitive performance: development of an ambulatory vigilance monitor.
abstract: BACKGROUND
  Limited opportunities to study human cognitive performance in non-laboratory, ambulatory situations exist. However, advances in technology make it possible to extend behavioral assessments to the field. One of the first devices to measure human behavior in the field was the wrist-worn actigraph. This device acquires minute-by-minute information on an individual's physical activity and can distinguish sleep from waking, the most basic aspect of behavior.
  
  
  METHODS
  Our laboratory developed a series of wrist-worn devices, not much larger than a watch, which assess reaction time, vigilance and memory. The devices concurrently assess motor activity with greater temporal resolution than standard actigraphs. They also continuously monitor multiple environmental variables including temperature, humidity, sound, and light.
  
  
  RESULTS
  These monitors have been employed during training and simulated military operations to collect behavioral and environmental information that would typically be unavailable under such circumstances. Development of the vigilance monitor, and how each successive version extended capabilities of the device are described. Data from several studies are presented, including studies conducted in harsh field environments during a simulated infantry assault, an officer training course.
  
  
  CONCLUSIONS
  The monitors simultaneously documented environmental conditions, patterns of sleep and activity and effects of nutritional manipulations on cognitive performance. They provide a new method to relate cognitive performance to real world environmental conditions and assess effects of various interventions on human behavior in the field. They can also monitor cognitive performance in real time, and if it is degraded, attempt to intervene to maintain
authors.affiliation: Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine, Natick, MA 01760, USA. harris.lieberman@na.amedd.army.mil
authors.forename: Harris R
authors.initials: HR
authors.lastname: Lieberman
authors.forename: F Matthew
authors.initials: FM
authors.lastname: Kramer
authors.forename: Scott J
authors.initials: SJ
authors.lastname: Montain
authors.forename: Philip
authors.initials: P
authors.lastname: Niro
mesh_terms: D001288:Attention / Q000502:physiology*; D003071:Cognition / Q000502:physiology*; D004867:Equipment Design; D006801:Humans; D008568:Memory / Q000502:physiology; D008889:Military Personnel; D008991:Monitoring, Physiologic / Q000295:instrumentation*; D011930:Reaction Time / Q000502:physiology; D012815:Signal Processing, Computer-Assisted