Summary and Critique by Claude Bingham
The researchers, Lufityanto, Donkin, and Pearson, sought to test just how much influence intuition can exert on decision-making accuracy, specifically emotionally-based intuition. Previous research had shown that the amount of nonconscious information plays a role in accuracy.
They coupled a random-dot-motion exercise with emotionally changed images that were shown nonconsciously to test participants via flash suppression. Using two control groups, and four experimental groups, they found there could be a link between intuition and unrelated categorical decision-making.
33% of the participants in the first experiment was exclude because they were not able to improve at tracking the random dot motions over time, their final sample size became 16, 7 males and 9 females. The control group was 10 subjects, 5 males and 5 females, who had previous psychophysical experience in lab settings.
When shown both negative and positive images that were consciously suppressed but intact, participants had an approximately 3% increase in accuracy, than when the image was scrambled. This was most clear when participants had not become used to the motion exercise.
The second experiment also had a sample size of 16, 6 males and 10 females. When adjusted for negative images vs positive images, the test participants showed no change in performance. Participants responded better to intact images than scrambled images; they showed higher confidence about decisions, faster reaction times, and higher accuracy.
The third experiment, which had 5 male and 11 female participants, showed similar increased accuracy and response when images were shown with a corresponding directional motion. When the researchers switched the direction, accuracy went back to neutral.
The final experiment, 22 participants (9 males, 13 females), sought to test how nonconscious information is tied to consciously available information. The results showed intact images were still linked to higher accuracy and using Skin Conductance Response, the researchers found participants were responding consciously to difficult random dot motions in concert with the nonconscious images.
This was a very technical research experiment with rigorous procedures to protect result integrity. Still, I feel there are holes in the test, such as individual participant reactions to particular emotional images may be the reverse of expected. Additionally, I am not sure a seemingly random situation, like random dot movements are an accurate approximation of non-random real-life situations that require people to use intuition, such as the movements of fellow drivers in traffic. Still, this experiment does show that subconsciously, our brains do make decision-related information processing outside of, and in addition to consciously available information.
Full research experiment available here: http://www.pearsonlab.org/images/human_intuition.pdf