No abstract

The functional linkage between platelet MAO activity and psychopathology was explored by analyzing temperamental correlates in 40 male subjects by means of scales from the Eysenck Personality Questionnaire (EPQ), the Zuckerman Sensation Seeking Inventory, and the Karolinska Scales of Personality (KSP). Linear correlations were found with two sensation seeking scales, replicating earlier findings. However, nonlinear correlations predominated. Subjects with intermediate platelet MAO activity had higher scores in conformity scales and lower scores in anxiety and hostility scales than low and high MAO subgroups. Low MAO subjects showed a pattern of higher scores in KSP Impulsiveness, EPQ Neuroticism, and KSP Somatic Anxiety and Irritability and lower scores in KSP Socialization, in line with personality profiles found in alcoholics, psychopaths, and suicide attempters who also tend to have low platelet MAO activity. High MAO subjects scored lower in sensation seeking and conformity scales and higher in KSP Psychasthenia, Muscular Tension and Suspicion scales, consistent with clinical links between high platelet MAO activity and anxiety and paranoia.

Fifty-eight normal adolescent Swedish boys, aged 16, provided two sets of blood samples for plasma testosterone assays as well as data on a number of personality inventories and rating scales assessing aggression, inpulsiveness, lack of frustration tolerance, extraversion, and anxiety. Physical variables such as pubertal stage, height, weight, chest circumference, and physical strength were measured. There was a significant association (r = 0.44) between plasma testosterone levels and self-reports of physical and verbal aggression, mainly reflecting responsiveness to provocation and threat. Lack of frustration tolerance was also related to testosterone levels. About 40% of the variance in perfectly reliable testosterone measurements could be predicted from equally reliable Physical + Verbal Aggression and Lack of Frustration Tolerance scales. Pubertal stage was correlated with testosterone (r = 0.44), but the above-mentioned relationships could not be accounted for by pubertal stage as a third common variable. Previous hypotheses relating testosterone to strong body build and antisocial behavior, respectively, received only weak or no support.