The impact of TMS-enhanced cognitive control on forgiveness processes

Cognitive control is thought to be necessary for forgiveness processes.

To examine this correlation, highly impulsive participants, who often fail to inhibit feelings of revenge, received activating theta burst stimulation (TBS) of a classical cognitive control region of the brain, the right dorsolateral prefrontal cortex (rDLPFC). For testing forgiveness ability participants received verum TBS versus sham TBS in a randomized, double-blinded, within-subjects design. In both sessions, they first learned that there are fair and unfair opponents in an ultimatum game, and subsequently played a dictator game with reversed roles with the option to revenge or forgive the opponents from the previous game.

Contrary to our hypothesis, activating TBS did not increase forgiving behavior toward unfair opponents. However, it increased the generosity toward previously fair opponents.

As an explanation it is discussed that the TBS can only affect "cold" emotions such as greed, but not the "hot" emotions such as anger.