Artículo de revista
Size and probability of rewards modulate the feedback error-related negativity associated with wins but not losses in a monetarily rewarded gambling task
Fecha
2010Registro en:
NeuroImage 51 (2010) 1194–1204
doi:10.1016/j.neuroimage.2010.03.031
Autor
San Martín, René
Manes, Facundo
Hurtado, Esteban
Isla, Pablo
Ibáñez, Agustín
Institución
Resumen
Feedback error-related negativity (fERN) has been referred to as a negative deflection in the event related
potential (ERP), which distinguishes between wins and losses in terms of expected and unexpected
outcomes. Some studies refer to the “expected outcome” as the probability to win vs. to lose, and others as
expected size of rewards. We still do not know much about whether these alternative interpretations of
“expected outcome” affect the fERN in a different manner, nor do we know the effect of their interaction in
an expected value fashion. We set a gambling task with four game categories; two had the same expected
value, while the other two categories were equivalent to the first ones, but alternatively in the size or
probability of the offered rewards. Results show that fERN preceded by a P200, and followed by a Pe-like
wave differentiates between losing in the category with a higher expected value and the rest of the
experimental conditions. fERN differentiates between wins and losses, but changes in the size and
probability of rewards impact the fERN amplitude only in win conditions. Results also show greater positivity
following win feedback when the size and/or probability of the outcome rewards were higher, so that the
higher the expected value the greater the positivity following win feedback. Our findings support the notion
that both the probability and size of the offered rewards modulate the motivational value for the win
feedback, this being also true for their interaction in an expected value fashion.