The neural correlates of happiness: A review of PET and fMRI studies using autobiographical recall methods.

Although very difficult to define, happiness is becoming a core concept within contemporary psychology and affective neuroscience. In the last two decades, the increased use of neuroimaging techniques has facilitated empirical study of the neural correlates of happiness. This area of research utilizes procedures that induce positive emotion and mood, and autobiographical recall is one of the most widely used and effective approaches. In this article, we review eight positron emission tomography and seven functional magnetic resonance imaging studies that have investigated happiness by using autobiographical recall to induce emotion. Regardless of the neuroimaging technique used, the studies conducted so far have shown that remembering happy events is primarily associated with the activation of many areas, including anterior cingulate cortex, prefrontal cortex, and insula. Importantly, these areas are also found to be connected with other basic emotions, such as sadness and anger. In the conclusion, we integrate these findings, discussing important limitations of the extant literature and suggesting new research directions.