Flicker sensitivity under conditions of chromatic adaptation

Abstract

Purpose. The temporal sensitivity of pi-mechanisms (chromatic and luminance) and the role of local and global adaptational processes were evaluated. Methods. Two-color incremeii thresholds were measured to evaluate Ihe pi-1 (BlueonYeEow), pi-4 (Yellow-on-Yellow) and pi-5 (Red-on-White) mechanisms over 4.2 log units of background luminance ( max 580 cd/m2). Sinusoidal flicker within a 2-sec cosine envelope was presented as a 1 °spot, 10° nasal (right eye) on a 15x30° background. Flicker modulated about an increment ranging from 0.6 to 2.3 log units above detection threshold. Three observers w ere tested with dilated pupils. Thresholds were determined with a staircase terminating after 6 rever..