Effects of absolute luminance and luminance contrast on visual search in low mesopic environments
Diverse adaptive visual processing mechanisms allow us to complete visual search tasks in a wide visual photopic range (>0.6 cd/m2). Whether search strategies or mechanisms known from this range extend below, in the mesopic and scotopic luminance spectra (<0.6 cd/m2), has yet to be addressed. Based on a study that addressed simple target discrimination in luminance environments using contrast-dependent behavioral efficiency functions, we assessed visual search in more complex-feature and conjunction-search paradigms. The results verify the previously reported deficiency windows defined by an interaction of base luminance and luminance contrast for more complex visual-search tasks. Based on significant regression analyses, a more precise definition of the magnitude of contribution of different contrast parameters. Characterized feature search patterns had approximately a 2.5:1 ratio of contribution from the Michelson contrast property relative to Weber contrast, whereas the ratio was approximately 1:1 in a serial-search condition. The results implicate near-complete magnocellular isolation in a visual-search paradigm that has yet to be demonstrated. Our analyses provide a new method of characterizing visual search and the first insight in its underlying mechanisms in luminance environments in the low mesopic and scotopic spectra.
Keywordsvisual search Color and Light: Contrast Color and Light: Lightness/Brightness
The authors would like to acknowledge funding support from the German Academic Exchange Service (DAAD) and the Cognitive Systems and Processes (COSYP) research center at Jacobs University Bremen.
- Goodman, T., Forbes, A., & Walkey, H. (2006). A practical model for mesopic photometry. Paper presented at the XVIII Imeko World Congress, Metrology for a Sustainable Development, Rio de Janeiro, Brazil.Google Scholar
- Kandel, E. R., & Wurtz, R. H. (2000). Constructing the visual image. In E. R. Kandel, J. H. Schwartz, & T. M. Jessell (Eds.), Principles of neural science (4th ed., pp. 492–506). Toronto, Canada: McGraw-Hill.Google Scholar
- Wolfe, J.M. (1994). Guided Search 2.0 A revised model of visual search. Psychonomic Bulletin & Review 1(2), 202–238.Google Scholar
- Wolfe, J. M. (1998). Visual search. In H. Pashler (Ed.), Attention. London, UK: University College London Press.Google Scholar
- Zele, A. J., Maynard, M. L., Joyce, D. S., & Cao, D. (2014). Effect of rod–cone interactions on mesopic visual performance mediated by chromatic and luminance pathways. Journal of the Optical Society of America A: Optics, Image Science, and Vision, 31(4), A7–A14.CrossRefPubMedPubMedCentralGoogle Scholar