TY  - JOUR
A1  - Cajar, Anke
A1  - Engbert, Ralf
A1  - Laubrock, Jochen
T1  - How spatial frequencies and color drive object search in real-world scenes
BT  - a new eye-movement corpus
JF  - Journal of vision
N2  - When studying how people search for objects in scenes, the inhomogeneity of the visual field is often ignored. Due to physiological limitations, peripheral vision is blurred and mainly uses coarse-grained information (i.e., low spatial frequencies) for selecting saccade targets, whereas high-acuity central vision uses fine-grained information (i.e., high spatial frequencies) for analysis of details. Here we investigated how spatial frequencies and color affect object search in real-world scenes. Using gaze-contingent filters, we attenuated high or low frequencies in central or peripheral vision while viewers searched color or grayscale scenes. Results showed that peripheral filters and central high-pass filters hardly affected search accuracy, whereas accuracy dropped drastically with central low-pass filters. Peripheral filtering increased the time to localize the target by decreasing saccade amplitudes and increasing number and duration of fixations. The use of coarse-grained information in the periphery was limited to color scenes. Central filtering increased the time to verify target identity instead, especially with low-pass filters. We conclude that peripheral vision is critical for object localization and central vision is critical for object identification. Visual guidance during peripheral object localization is dominated by low-frequency color information, whereas high-frequency information, relatively independent of color, is most important for object identification in central vision.
KW  - scene viewing
KW  - eye movements
KW  - object search
KW  - central and peripheral
KW  - vision
KW  - spatial frequencies
KW  - color
KW  - gaze-contingent displays
Y1  - 2020
U6  - https://doi.org/10.1167/jov.20.7.8
SN  - 1534-7362
VL  - 20
IS  - 7
PB  - Association for Research in Vision and Opthalmology
CY  - Rockville
ER  -