Amplitude of low-frequency fluctuations in happiness: A resting-state fMRI study

Abstract

Happiness is a universal pursuit; however, not everyone is equipped with the same ability to be happy. Therefore, it is important to investigate the individual differences that affect happiness. Little attention has been devoted to understanding the neural basis of individual differences in happiness. We thus used the amplitude of low-frequency fluctuations (ALFF) in resting-state functional magnetic resonance imaging (fMRI) to study the relationship between happiness and spontaneous brain activity in 159 healthy participants. The results showed that ALFF values for the frontal, parietal and parts of subcortical areas were associated with happiness. Specifically, the ALFF values in the left and right orbitofrontal cortex, left dorsolateral prefrontal cortex, and right caudate positively predicted happiness. Furthermore, these areas were significantly correlated with participants emotional states. By contrast, the ALFF values in the right middle cingulate gyrus, superior parietal lobule, and bilateral precuneus negatively predicted happiness, and were not only correlated with emotions, but also with rumination. These findings indicate that there may be underlying systematic differences in self-reflection, reward processing, emotion, and emotional regulation between happy and unhappy individuals.