In the present study, we investigated whether luminance
and the side of response execution are associated,
showing a SNARC-like effect (faster responses with the left
hand for dark stimuli, and vice versa for light stimuli).
A total of 30 participants were tested in two experiments. In
Experiment 1, the association between space and the luminance
of chromatic stimuli was directly tested (brightness
discrimination). In Experiment 2, the same spatial association
was tested indirectly (hue discrimination). The results showed
that participants responded faster with their left hand to hues
with lower luminance, and with their right hand to hues with
higher luminance, in either the direct or the indirect task. The
consistency of this association in both tasks demonstrates the
automaticity of the SNARC-like effect for luminance.
