Regional homogeneity of intrinsic brain activity in happy and unhappy individuals.
BACKGROUND
Why are some people happier than others? This question has intrigued many researchers. However, limited work has addressed this question within a neuroscientific framework.


METHODS
The present study investigated the neural correlates of trait happiness using the resting-state functional magnetic resonance imaging (rs-fMRI) approach. Specifically, regional homogeneity (ReHo) was examined on two groups of young adults: happy and unhappy individuals (N = 25 per group).


RESULTS
Decreased ReHo in unhappy relative to happy individuals was observed within prefrontal cortex, medial temporal lobe, superior temporal lobe, and retrosplenial cortex. In contrast, increased ReHo in unhappy relative to happy individuals was observed within the dorsolateral prefrontal cortex, middle cingulate gyrus, putamen, and thalamus. In addition, the ReHo within the left thalamus was negatively correlated with Chinese Happiness Inventory (CHI) score within the happy group.


CONCLUSIONS
As an exploratory study, we examined how general trait happiness is reflected in the regional homogeneity of intrinsic brain activity in a relatively small sample. Examining other types of happiness in a larger sample using a multitude of intrinsic brain activity indices are warranted for future work.


CONCLUSIONS
The local synchronization of BOLD signal is altered in unhappy individuals. The regions implicated in this alteration partly overlapped with previously identified default mode network, emotional circuitry, and rewarding system, suggesting that these systems may be involved in happiness.
Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing, China ; Faculty of Psychology, Southwest University, Chongqing, China.
Yangmei
Y
Luo
Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing, China ; Faculty of Psychology, Southwest University, Chongqing, China.
Xiting
X
Huang
Center for the Developing Brain, Child Mind Institute, New York, New York, United States of America.
Zhen
Z
Yang
Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing, China ; Faculty of Psychology, Southwest University, Chongqing, China.
Baolin
B
Li
Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing, China ; Faculty of Psychology, Southwest University, Chongqing, China.
Jie
J
Liu
Key Laboratory of Cognition and Personality (SWU), Ministry of Education, Chongqing, China ; Faculty of Psychology, Southwest University, Chongqing, China.
Dongtao
D
Wei
D001921:Brain / Q000502:physiology*; D016022:Case-Control Studies; D006240:Happiness; D006801:Humans; D009483:Neuropsychological Tests