Disentangling competence from performance in behavioral measures of learning: A lesson for cognitive neuroscience

In cognitive neuroscience, the momentary learning performance and the underlying competence on a behavioral task are typically not distinguished, which can lead to unreliable measures of brain-behavior relationships. Here we aimed to disentangle competence from performance by examining two groups with different (speed or accuracy) instructions in the learning phase and with the same instruction (focusing on both) in the testing phase. Healthy young adults performed an implicit probabilistic learning task in two sessions. In the learning phase, the two groups showed similar learning measured by reaction times; however, only the group with speed instruction showed learning measured by accuracy. In the testing phase, a similar level of knowledge was found in both measures. Overall, multiple sessions with different instructions enabled the separation of competence from performance. Additionally, reaction time measures seemed to be more resistant to speed/accuracy instructions. These findings can help create better experimental designs for cognitive neuroscience studies.