Traffic Sign Conspicuity: The Effects of Clutter,Luminance,and Age

Abstract

The effects of visual clutter, luminance, and aging on traffic sign conspicuity were examined in two experiments. Experiment 1a evaluated clutter using subjective judgments from 28 older and younger observers. Participants categorized daytime and nighttime traffic scenes into high or low clutter. Using these categorized scenes, in Experiment 1b a new sample of 28 younger and older participants visually searched for traffic signs. Reaction time and eye movement data were analyzed. Results suggested that aging and clutter affect con-spicuity. Moreover, older adults had poorer performance on target-absent trials. No luminance effect or any age by clutter interactions were obtained. Expertise gained through many years of driving may dampen clutter effects experienced by older adults. The nonlinear relationship between fixation frequency and fixation duration is discussed in relation to similar findings in experimental visual search. Results suggest that age differences found in processing simple visual stimuli may not generalize to more naturalistic scenes.

Get full access to this article

View all access options for this article.

References

Dollinger

S. C.

Hoyer

W. J.

(1996). Age and skill differences in the processing demands of visual inspection. Applied Cognitive Psychology, 10 (3), 225–239.

Jenkins

S. E.

Cole

B. L.

(1984). Daytime conspicuity of road traffic control devices (Rep. No. AIR 386-1). Melbourne: Australian Road Research Board.

Kline

D. W.

Scialfa

C. T.

(1997). Sensory and perceptual functioning: Basic research and human factors implications. In Fisk

A.D.

Rogers

W. A.

(Eds.), Handbook of human factors and the older adult (pp. 27–54). San Diego: Academic Press.

Moer

R. C.

(1998). Manual on traffic signs. [On-line]. Available: members.aol.com/rcmoeur.

Plude

D. J.

Doussard-Roosevelt

J. A.

(1989). Aging, selective attention, and feature integration. Psychology & Aging, 4, 98–115.

Schieber

Goodspeed

C. H.

IV (1997). Nighttime con-spicuity of highway signs as a function of sign brightness, background complexity and age of observer. Proceedings of the Human Factors and Ergonomics Society 41st Annual Meeting (pp. 1362–1366). Santa Monica, CA: Human Factors and Ergonomics Society.

Scialfa

C. T.

Joffe

K. M.

(1998). Response times and eye movements in feature and conjunction search as a function of target eccentricity. Perception & Psychophysics, 60 (6), 1067–1082.

Scialfa

C. T.

Joffe

K. M.

(1997). Age differences in feature and conjunction search: Implications for theories of visual search and generalized slowing. Aging, Neuro-psychology, and Cognition, 4 (3), 227–246.

Scialfa

C. T.

Thomas

D. M.

Joffe

K. M.

(1994). Age differences in the useful field of view: An eye movement analysis. Optometry and Vision Science, 71 (12), 736–742.

10.

Shoptaugh

C. F.

Whitaker

L. A.

(1984). Verbal response times to directional traffic signs embedded in photographic street scenes. Human Factors, 26 (2), 235–244.

11.

Sivak

Olson

P. L.

Pastalan

L. A.

(1981). Effect of drivers' age on nighttime legibility of highway signs. Human Factors, 23 (1), 59–64.

12.

Theeuwes

(1996). Visual search at intersections: An eye-movement analysis. In Gale

A. G.

Brown

I. D.

Haslegrave

C. M.

Taylor

S. P.

(Eds.), Vision in Vehicles-V (pp. 125–134). North-Holland: Elsevier Sciences.

13.

Winer

B. J.

(1962). Statistical principles in experimental design. New York: McGraw-Hill.

14.

Zelinsky

G. J.

Sheinberg

D. L.

(1997). Eye movements during parallel-serial visual search. Journal of Experimental Psychology: Human Perception & Performance, 23 (1), 244–262.