paired with the other four symbols to create 8 new pairs for a total of 96 trials, and no feedback is given during the test. The results were tallied according to the proportions of trials in which symbol A was chosen over other symbols or symbol B was avoided when paired with other symbols. Performance on ‘’Choose A’’ pairs was used as a measure of positive-reinforcement learning, whereas performance on ‘’Avoid B’’ pairs reflected negative-reinforcement learning.
