Abstract: People can generate anticipations from the environmental events and comparing them with the actual results constantly, by evaluating outcomes of feedback information to facilitate the performance of the behavior. Outcome evaluation, the process of evaluation that people act on their own or through external feedback results, is an important cognitive function of human. In event-related potential (ERP) research on the outcome evaluation or feedback processing, feedback-related negativity (FRN) and P300 were important components particularly induced by evaluating performance outcomes in adult subjects. Adopting a paradigm of lottery gambling task and manipulating the reward-related certainty, the present study investigated the cognitive and neural electrophysiological processes of outcome anticipation and evaluation in young adolescents, and compared the results with adults’, which as the control group.
Event-related brain potentials (ERPs) were measured when 15 healthy right-handed junior high school students did a lottery-gambling task. The participants were told that the red ball would immediately stop on the box it was passing by once they press the button. The red ball stopping on the green part indicates their gain, whereas, the gray part indicates their loss in the trail. We mainly analyzed ERPs elicited by the gain and loss feedback outcomes following two certainty conditions.
The results showed that: Feedback Related Negativity which reflects the automatic rapid outcome evaluation showed not significant differences between adolescents and adults, whether in the high or low certainty condition. whereas, P300 which reflects the controlled elaborately outcome evaluation of the functional significance of feedback stimulus was sensitive both to groups and certainty conditions, which showed a significant interaction. Simple effects analysis showed that, in the high-certainty condition, the difference between amplitude of P300 elicited by gain and loss were significant in adolescents; however, there were not significant differences in adults for the P300 amplitude between gain and loss.
These results revealed that the young adolescents had showed different trends in the development of abilities to automatic rapid and controlled elaborate of outcome evaluations and functional significance of feedback simulation. The ability of adolescents to evaluate feedback stimulation rapidly was close to the level of adults, but their ability to controlled elaborate outcome evaluation of the functional significance of feedback stimulation was developmentally underactive.

Key words: young adolescents, outcome prediction, outcome evaluation, FRN, P300