Probabilistic Selection Task TASK

Unreviewed

The probabilistic selection task assesses whether participants learn better from positive or negative reinforcement. The subject is instructed to choose between abstract stimuli via key press. The task is composed of two phases. During the first phase, subjects learn to associate 6 abstract visual stimuli with different reward probabilities (e.g., stim 1= 80%, stim 2 = 70%, stim 3= 60%, stim 4= 40%, stim 5 = 30%, stim 6= 20%). In phase 1, the various stimuli are always presented in pairs, where the sum of the two reward probabilities associated with each stimuli equal 100%. For example, stim 1 will always be paired with stim 6 (80%+20%=100%). Subjects eventually learn that for each pair, choosing one stimuli over the other results in more reward (80%>20%). The subject is tested on this association in phase two. During phase two, the subject must decide between novel combinations of stimuli. Each stimuli is presented with the remaining four stimuli that it was not paired with in phase 1. For example, stim1 (80%) can be paired with either stim2(70%), stim3(60%), stim4(40%), or stim5(30%), but not with itself or with the stimuli it was associated with during phase 1, stim6 (20%). Subjects are instructed to win as many points as possible. There is no feedback given during the second phase.

Definition contributed by Anonymous
neurovault