title: Randomness of resting-state brain oscillations encodes Gray's personality trait.
abstract: Randomness of functional Magnetic Resonance Imaging (fMRI) resting-state time-series has recently been used as a biomarker for numerous disorders including Alzheimer's and Parkinson's disease as well as autism. To date, however, it remains unknown whether and to what degree personality traits are associated with the randomness of resting-state temporal dynamics. To investigate this question, we estimated the Hurst exponent - a measure of the randomness of a time-series - during resting-state fMRI in brain areas previously associated with trait Impulsivity as defined in Gray's Reinforcement Sensitivity Theory of Personality in 15 healthy individuals. The Hurst exponent in the ventral striatum as well as in the orbitofrontal cortex (OFC) was significantly associated with the measure of Gray's trait Impulsivity. Specifically, more random resting-state neural dynamics corresponded to higher Impulsivity scores both in the ventral striatum (r(15)=-.71; p=.003) and the OFC (r(15)=-.81; p<.001). In summary, we provide evidence for an association between individual differences in Gray's Impulsivity and randomness in key areas of the reward system which have previously been associated with this personality trait. Based on evidence from fMRI and electroencephalographical studies, we suggest that this association might arise from resting-state fluctuations constraining task-related neural responsiveness. Thereby, we outline a potential mechanism linking randomness of resting-state dynamics and personality.
authors: Department of Cognitive Psychology II, Johann Wolfgang Goethe University Frankfurt/Main, Germany. TimHahn@gmx.net
authors: Tim
authors: T
authors: Hahn
authors: Thomas
authors: T
authors: Dresler
authors: Ann-Christine
authors: AC
authors: Ehlis
authors: Martin
authors: M
authors: Pyka
authors: Alica C
authors: AC
authors: Dieler
authors: Claudia
authors: C
authors: Saathoff
authors: Peter M
authors: PM
authors: Jakob
authors: Klaus-Peter
authors: KP
authors: Lesch
authors: Andreas J
authors: AJ
authors: Fallgatter
mesh_terms: D000328:Adult; D001683:Biological Clocks; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods; D003627:Data Interpretation, Statistical; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D007175:Impulsive Behavior / Q000175:diagnosis* / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009415:Nerve Net / Q000503:physiopathology; D010552:Personality Assessment; D015203:Reproducibility of Results; D012146:Rest; D012680:Sensitivity and Specificity; D055815:Young Adult