Twelve experienced navigators participated in an experiment to determine the effects of alcohol, caffeine, and an alcohol+caffeine mixture on performance during the following tasks: visual search, the search and location of items on a navigational chart (chart search) and the solving of maritime navigational problems. Alcohol (75 ml) produced impairment in performance on visual search (p less than 0.05) and navigational problem-solving (p less than 0.01). Caffeine was found to enhance performance on visual search (p less than 0.05) but not on the chart search, although a significant correlation was found between performance on the two tests (p less than 0.05). Caffeine was not found to improve the accuracy of navigational problem-solving (p greater than 0.05). Neither alcohol nor caffeine had any significant effect on the speed of problem-solving (p greater than 0.05). (A)
Samenvatting