Detection of colour change in moving objects: temporal order judgment and reaction time analysis.
The time needed to detect changes in the colouration of a single moving stimulus becomes shorter with its increasing velocity (Kreegipuu et al, 2006 Vision Research 46 1848-1855). We examined the ability to detect colour change in moving chromatic bars or sinusoidal gratings through temporal order judgment (TOJ) and reaction time (RT) tasks to test whether the effect of velocity found in a previous study is universal and holds for different tasks and stimuli. The results demonstrate that the TOJ and simple RT to the colour change of a moving grating are insensitive to stimulus velocity. Therefore, we conclude that the process of comparison of the two internal representations of external events does not have access to temporal information precise enough to estimate the exact time when something enters our subjective awareness. The motion effect on colour-change perception seems to be confined to a single stimulus that moves across the visual field, to events that contain some spatial predictability, and to tasks that reflect the time of the change relatively directly.
Murd
Carolina
C
Institute of Psychology and the Estonian Center of Behavioral and Health Sciences, University of Tartu, Tiigi 78, Tartu 50410, Estonia. Carolina.Murd@ut.ee
Kreegipuu
Kairi
K
Allik
Jüri
J
D000328:Adult; D000704:Analysis of Variance; D003118:Color Perception / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D011930:Reaction Time / Q000502:physiology; D055815:Young Adult