The regulation of emotions is an ongoing internal process and often a challenge. Current related neural models concern the intended control of reactions towards external events, mediated by prefrontal cortex regions upon basal emotion processing as in the amygdala. Cognitive strategies to regulate emotions in the context of affective disorders or stress reduction, increasingly applied in clinical practice, are also related to mindfulness techniques. We questioned their effects on neural emotion processing and investigated brain activity during purely internal mental self-referential processes of making current emotions and self-related cognitions aware. Thirty healthy subjects performed a task comprising periods of cognitive self-reflection, of introspection for actual own emotions and feelings, and of a neutral condition, while they were scanned with functional magnetic resonance imaging. Brain activations of twenty-seven subjects during emotion-introspection and self-reflection, and also a conjunction of both, were compared with the neutral condition. The conditions of self-reflection and emotion-introspection showed distinguishable activations in medial and ventrolateral prefrontal areas, in parietal regions and in the amygdala. Notably, amygdala activity decreased during emotion-introspection and increased compared to 'neutral' during self-reflection. The results indicate that already the self-referential mental state of making the actual emotional state aware is capable of attenuating emotional arousal. This extends current theories of emotion regulation and has implications for the application of mindfulness techniques as a component of psychotherapeutic strategies in affective disorders and also for possible everyday emotion regulation.