The impact of TMS-enhanced cognitive control on forgiveness processes

Forgive or complain: Interpersonal distance modulates reactive attitudes and neural responses toward wrongdoers

While the effect of interpersonal distance on forgiveness has been investigated over the past few years, it remains unclear whether this facilitating effect holds even when measured implicitly. Meanwhile, though cognitive control and the corresponding prefrontal cortex play a prominent role in forgiveness processing, the neural mechanism underlying forgiveness toward varied wrongdoers is largely unexplored. Here, forty-two participants initially underwent noise offense either from their friend or stranger, followed by a word identification test to examine their implicit attitude, during which they were presented with word-name combinations and required to categorize forgive- or complain-label words while ignoring the names of their friends or strangers below. A shorter reaction time reflects more congruence with one's implicit attitude. Electroencephalogram was recorded during the word identification test. Behaviorally, while individuals reacted faster to forgive-friend relative to complain-friend pairings, no such reaction bias was found for the stranger-wrongdoer, which suggests that individuals were more inclined to forgive someone close. Regarding the EEG/ERP results, forgive-friend elicited lower alpha oscillation and more negative frontal alpha asymmetry (FAA) value than complain-friend combinations, suggesting increased and dominant activity in the right prefrontal network during forgiveness toward friends. Whereas complain- relative to forgive-stranger combinations elicited larger P3 amplitudes, suggesting a neural encoding bias to information associated with complaints about stranger-wrongdoer. These multimodal findings provide evidence for the benefits of closeness in forgiveness and shed light on the neural mechanisms underlying forgiveness toward different types of wrongdoers.

Connectome-based predictive modeling of trait forgiveness

Forgiveness is a positive, prosocial manner of reacting to transgressions and is strongly associated with mental health and well-being. Despite recent studies exploring the neural mechanisms underlying forgiveness, a model capable of predicting trait forgiveness at the individual level has not been developed. Herein, we applied a machine-learning approach, connectome-based predictive modeling (CPM), with whole-brain resting-state functional connectivity (rsFC) to predict individual differences in trait forgiveness in a training set (dataset 1, N = 100, 35 men, 17-24 years). As a result, CPM successfully predicted individual trait forgiveness based on whole-brain rsFC, especially via the functional connectivity of the limbic, prefrontal and temporal areas, which are key contributors to the prediction model comprising regions previously implicated in forgiveness. These regions include the retrosplenial cortex, temporal pole, dorsolateral prefrontal cortex (PFC), dorsal anterior cingulate cortex, precuneus and dorsal posterior cingulate cortex. Importantly, this predictive model could be successfully generalized to an independent sample (dataset 2, N = 71, 17 men, 16-25 years). These findings highlight the important roles of the limbic system, PFC and temporal region in trait forgiveness prediction and represent the initial steps toward establishing an individualized prediction model of forgiveness.

The impact of TMS-enhanced cognitive control on forgiveness processes

BACKGROUND

Cognitive control is thought to be necessary for forgiveness processes.

MATERIALS AND METHODS

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.

RESULTS

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

CONCLUSION

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.