Deric Bownds has an excellent post about a proposed neurological mechanism for mellowing as we age. This study to me represents an example of good work that can be done using brain imaging. (Although we pointed to an article critical of fMRI last week, this was by no means meant to suggest that fMRI research can't be valuable. Smooth Pebbles has a good list of other valuable fMRI studies.)
Here's how Bownds describes the study:
They used fMRI (function Magnetic Resonance Imaging) or ERP (Event related potentials recorded on the surface of the scalp) to examine the activity of the medial prefrontal cortex (MPFC) that is central in inhibiting or enhancing emotional functions. Subject also rated their own reactions to photographs shown during the measurements of fearful, happy, or neural faces. A shift in responses to positive versus negative emotion over age was seen in both recognition and brain function. Recognition of negative emotion (fear, shown in red in right part of figure) showed a significant decline as a function of increasing age, whereas recognition for positive emotion (happiness) increased.
Research such as this adds another data point: converging evidence which supports other, cognitive research, all pointing to an explanation of the phenomenon of mellowing with age. One of the ways in which fMRI can be at its best is when it helps piece together the puzzles that other research uncovers.