References  

Inattentional Blindness in Simulated Driving Environments!Justin M. Ericson1, Melissa R. Beck1, Scott A. Parr2, & Brian Wolshon2!

Louisiana State University: Psychology1; Civil and Environmental Engineering2!

Gulf Coast Center for Evacuation and Transportation Resiliency!

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Track 1!

Track 2!

Changes in Steering (deg)!

Steering Deviations!

Results  

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RT

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Brake RT!Sparse Clutter!

Dense Clutter!

Method  •  Realtime Technologies Inc. driving simulator!

Sparse Clutter Example! Dense Clutter Example!

•  Participants (n = 156)!•  LSU students with state issued drivers licenses!

•  Procedure – 3 runs!•  1 Pre-trial run with no localized clutter or tracking!•  1 Run without pedestrian entering road!•  1 Test run with the unexpected pedestrian entering the road!

•  H1: Higher tracking loads (more vehicles) will impair reactions to an unexpected pedestrian.!

•  H2: Densely cluttered environments will impair reactions to an unexpected pedestrian!

•  Roadway!•  Two S-Curves!•  2 intersections without crossing traffic and no stops for

participant!•  Tracked Vehicles!•  Red cars changing lanes in front of participant!•  33.54 mph!

H1: Tracking Load - F(1,151) = 5.92, p = .02, ηp2 = .04 !

H2: Clutter - F(1,151) = 4.40, p = .01, ηp2 = .05 !

H1: Tracking Load - F(1,134) = 5.08, p = .03, ηp2 = .04 !

Right  Turn  Le-  Turn  

•  Tracking Load!•  1 of 2 cars vs. 2 of 4 cars!

•  Clutter!•  Sparse vs. Dense!

•  Response to Unexpected Pedestrian!•  Braking measures!•  Change in Velocity!•  Brake RT!

•  Steering Deviations!

Independent Variables! Dependent Variables!

Background  

Unexpected Pedestrian!•  Always between the 2

intersections!•  Ran into road at same location

in all conditions!•  Data presented comes from

the Test Run only!

Hypotheses  

Conclusions  

* Participants who did not brake were removed from RT analysis!

•  Distracted Drivers will adjust driving habits to accommodate secondary tasks (e.g. cell phones, radio, or GPS) (Young & Regan, 2007).!•  Reduce speed!•  Greater headway!•  Allocate attention to other duties (e.g. checking mirrors, traffic

patterns, etc.)!•  Distractions are not limited to within the vehicle, as distractions

outside the vehicle can also attract attention (Land & Lee, 2004).!•  Distractions requiring attentional resources outside the vehicle can

lead to Inattentional Blindness: the inability to detect or delayed detection of information presented directly in front of the observer (Simons & Chabris, 1998; Hyman et al., 2009).!

•  Attentional resources used while driving!•  Target/Vehicle tracking load (Lochner & Trick, 2011)!•  Object tracking utilizes attentional resources that prevent

completion of other tasks (Tombu & Seiffert, 2008).!•  Visual clutter in the environment!•  Environmental complexity can cause participants to miss

critical information (Stinchcombe & Gagnon, 2010).!•  Increasing visual clutter slows reaction times (RT) (Beck et al.,

2010).!•  How do these loads on attention affect detection of critical objects

(e.g., a pedestrian entering the roadway)?!

•  H1: !•  Tracking load increases braking RT and steering deviations to the

pedestrian.!•  Drivers may over compensate with steering deviations due to

slower braking.!•  H2: !•  Densely cluttered environments cause an overall smaller change

in velocity, indicating the tendency to brake less.!

Email: jerics1@lsu.edu Web: http://justinmericson.wix.com/justinericson !

Beck, M.R., Lohrenz, M.C., & Trafton, J.G. (2010). Measuring Search Efficiency in Complex Visual Search Tasks: Global and Local Clutter. Journal of Experimental Psychology: Applied, 16(3),238-250.!

Hyman, I. E., Jr, Boss, S. M., Wise, B. M., McKenzie, K. E., & Caggiano, J. M. (2009). Did you see the unicycling clown? Inattentional blindness while walking and talking on a cell phone. Applied Cognitive Psychology, 24(5), 597–607. doi:10.1002/acp.1638!

Land, M. F., & Lee, D. N. (1994). Where we look when we steer. Nature, 369, 742-744.!Lochner, M. & Trick, L. (2011). Attentional tracking of multiple vehicles in a highway driving scenario. Proceeding s of the Sixth International Symposium on

Human Factors in Driver Assessment, Training and Vehicle Design. drivingassessment.uiowa.edu !Simons, D., & Chabris, C. (1999). Gorillas in our midst: Sustained inattentional blindness for dynamic events. Perception, 28, 1059-1074!Stinchcombe, A., & Gagnon, S. (2010). Driving in dangerous territory: Complexity and road-characteristics influence attentional demand. Transportation

Research Part F: Psychology and Behaviour, 13(6), 388–396. Elsevier Ltd. doi:10.1016/j.trf.2010.06.008!Tombu, M., & Seiffert, A. E. (2008). Attentional costs in multiple-object tracking. Cognition, 108(1), 1–25. doi:10.1016/j.cognition.2007.12.014!Young, K. & Regan, M. (2007). Driver distraction: A review of the literature. In: I.J. Faulks, M. Regan, M. Stevenson, J. Brown, A. Porter & J.D. Irwin (Eds.).

Distracted driving. Sydney, NSW: Australasian College of Road Safety. Pages 379-405!

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