Improving driving performance while fatigued. Can a secondary task—such as a word association task—

improve your performance when driving while fatigued?

This was the question of interest in a Human Factors

(May 2014) study. The researchers used a driving simulator to obtain their data. Each of 40 college students was assigned to drive a long distance in the simulator.

However, the student-drivers were divided into four groups of 10 drivers each. Group 1 performed the verbal task continuously (continuous verbal condition); Group 2 performed the task only at the end of the drive (late verbal condition); Group 3 did not perform the task at all (no verbal condition); and Group 4 listened to a program on the car radio (radio show condition). At the end of the simulated drive, drivers were asked to recall billboards that they saw along the way. The percentage of billboards recalled by each student-driver is provided in the next table. Use the information in the accompanying SPSS printout to determine if the mean recall percentage differs for student-drivers in the four groups. Test using a = .01.

Data for Exercise 10.38 Continuous Radio Verbal Late Verbal No Verbal Show 14 57 64 37 89985 63 64 83 10 66 54 29 18 59 37 95 60 60 52 39 43 58 56 4 92 73 36 85 78 47 47 73 645848448 87 62 14 59 50 SPSS Output for Exercise 10.38 RECALL ANOVA Sum of Squares df Mean Square F Sig. Between Groups 5921.700 3 1973.900 5.388 .004 Within Groups 13189.400 36 366.372 Total 19111.100 39