The neural foundation of moral decision-making

The nature of moral judgments has received considerable attention
not only in philosophy and psychology but lately in neuroscience as
well. There are two major paradigms that consider moral judgments
either mainly rational, or as emotional-/ intuition-based
processes. Relatively recent neuroimaging studies revealed however
that both rational and emotional processes may support moral
judgments. In line with these results, this doctoral thesis focused
on ways that could better elucidate the supporting cognitive and/
or emotional processes of moral judgments. In a first study, moral
judgments were compared to esthetic judgments by employing a
whole-brain analysis. This idea was based on the philosophical and
the psychological frameworks of moral sense theory and social
intuitionist model respectively. Both models view moral judgments
akin to esthetic judgments, as decision-making processes based on
emotions/ subjective feelings. The fMRI data suggest a common
denominator between the judgment modalities - a network involved in
both cognitive and emotion processing. However, moral judgments
seem to rely on an additional social component. In a second fMRI
study, the two main paradigms of moral research were investigated.
A main difference between the paradigms is the perspective the
participants have towards the moral stimuli (i.e. first- or
third-perspective). The fMRI data revealed that neural differences
may emerge, and that they may be related to the so-called
“actor-observer bias”, a tendency to attribute one’s own behavior
to the situation, and the behaviors of others to their inner
characteristics. Several hypotheses are put forth, which try to
explain the complex neural mechanisms of moral decision-making.