Evidence for a priming-based asymmetry in color identification

ABSTRACT

Performance asymmetries in colour discrimination (or detection) between visual fields (VFs) are typically examined using mean or median reaction times and have tended to yield either a left VF advantage for all colours (i.e., lower reaction times) or no difference for any colour, although a right VF advantage has also been reported. We used a novel colour identification task in which participants simply identified the colour of a laterally presented rectangle (i.e., red or blue). A measure of priming effects – but not mean or median reaction times – revealed a VF × colour interaction across a pilot study and two experiments; priming for red versus blue stimuli was greater in the left VF and priming for blue stimuli was greater in the right versus left VF. Two plausible psychological explanations of this interaction are offered, including the potential generation of approach and avoidance motivations and different emotional responses to blue versus red stimuli. Future work will be needed, but the current findings indicate that the left and right hemispheres are differentially primed by different colours – the right hemisphere is primed to a greater extent by red stimuli, and the left hemisphere is primed more by blue stimuli.

KEYWORDS:

• Color identification
• asymmetry
• priming
• approach/avoidance
• valence hypothesis

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1 It was important to control for variance related to participants “error rate” in Experiment 2 even though this variable only accounted for significant variance in one out of twelve conditions (Gray presented over a blue background in RVF/LH, r(27) = .42, p < .04). This allowed us to remove variance related to poor performance, which removed random noise from the data that may have been due to lower effort on the task, although there was no clear pattern to the influence of error rate on priming magnitude; without this variable included in the analysis, the interaction term was completely obscured, F < 1. The greater potential difficulty of the task in Experiment 2 may explain why it was necessary to account for error variance in this study but not Experiment 1, but this is not clear. It is likely, though, that the results of Experiment 1 would have been even stronger if we were able to account for this variance. Eye tracking equipment should be used in future studies to remove error trials, but this was not possible in the current experiments due to a lack of eye tracking equipment.