Personality Traits and Striatal Dopamine Synthesis Capacity in Healthy Subjects

• Published in: The American journal of psychiatry Vol. 160; no. 5; pp. 904 - 910
• Main Authors: Laakso, Aki, Wallius, Esa, Kajander, Jaana, Bergman, Jörgen, Eskola, Olli, Solin, Olof, Ilonen, Tuula, Salokangas, Raimo K.R., Syvälahti, Erkka, Hietala, Jarmo
• Format: Journal Article
• Language: English
• Published: Washington, DC American Psychiatric Publishing 01.05.2003; American Psychiatric Association
• Subjects: Adult; Age Factors; Anxiety; Behavior; Biological and medical sciences; Brain imaging; Caudate Nucleus - diagnostic imaging; Caudate Nucleus - metabolism; Caudate Nucleus - physiology; Corpus Striatum - diagnostic imaging; Corpus Striatum - metabolism; Corpus Striatum - physiology; Dopamine; Dopamine - biosynthesis; Dopamine - physiology; Female; Fluorodeoxyglucose F18; Functional Laterality - physiology; Fundamental and applied biological sciences. Psychology; Humans; Irritable Mood - physiology; Linear Models; Male; Middle Aged; Neurochemicals; Neurology; Personality; Personality - classification; Personality - physiology; Personality Assessment - statistics & numerical data; Personality Disorders - diagnosis; Personality Disorders - diagnostic imaging; Personality Disorders - physiopathology; Personality traits; Personality. Affectivity; Psychiatry; Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Putamen - diagnostic imaging; Putamen - physiology; Putamen - physiopathology; Sex Factors; Social Desirability; Tomography, Emission-Computed; Radionuclide study; Human; Healthy subject; Presynaptic transmission; Central nervous system; Personality; Putamen; Deviance conformity; Biological fixation; Caudate nucleus; Extraversion introversion; Occipital cortex; Young adult; Adult; Anxiety; Comparative study; Aggressiveness; Brain (vertebrata); Positron; Emission tomography
• ISSN: 0002-953X; 1535-7228
• DOI: 10.1176/appi.ajp.160.5.904

OBJECTIVE: Neuroimaging and genetic studies suggest that individual differences in the brain dopaminergic system contribute to the normal variability of human personality (e.g., social detachment and novelty seeking). The authors studied whether presynaptic dopamine function is also associated with personality traits. METHOD: Presynaptic dopamine synthesis capacity in the brain was measured with positron emission tomography and [18F]fluorodopa in 33 healthy adults, and personality traits were assessed with the Karolinska Scales of Personality. Associations were studied by using a linear regression model controlling for the effects of age and gender on both variables. RESULTS: High scores on two of the anxiety-related personality scales, somatic anxiety and muscular tension, and on one aggressivity-related scale, irritability, were significantly associated with low [18F]fluorodopa uptake in the caudate. No statistically significant associations were observed between [18F]fluorodopa uptake and the detachment scale or scales related to novelty-seeking behavior (impulsiveness and monotony avoidance). CONCLUSIONS: The results suggest a role for the dopaminergic system in the regulation of anxiety in healthy subjects. Together with previous studies, they also indicate differential involvement of various components of the dopaminergic system in normal and pathological personality traits.