It seems like there are a lot of commenters claiming to be able to do the same thing who didn't read the abstract:
"...various indirect mechanisms possibly mediating this phenomenon were tested: accommodation, brightness, increases in arousal by increased mental effort. None of these behavioral tests could support an indirect strategy as the mode of action"
"...various indirect mechanisms possibly mediating this phenomenon were tested: accommodation, brightness, increases in arousal by increased mental effort. None of these behavioral tests could support an indirect strategy as the mode of action"