Psychophysiological traits of men with several genotypes in polymorphic locus Val158Met COMT and different levels of aggressiveness

Background. The catechol-O-methyl transferase gene influences the reuptake of monoamines (dopamine, serotonin, noradrenaline) from the synaptic space. The structural peculiarities of this gene are linked with the duration of stay of neurotransmitters in the synaptic gap and the emergence and duration of emotional reactions, which may considerably affect a person’s level of aggressiveness; these peculiarities may manifest as psychophysiological characteristics. Objective and design. This study investigated the amplitude, spatio-temporal traits and sources of evoked brain activity in men with several genotypes in the polymorphic locus Val158Met in the COMT (Catechol-O-methyl transferase) gene, levels of aggressiveness using the Buss-Darkee inventory, proneness to various types of deviant and addictive behaviors in accordance with the methods of A.N. Oryol and the preferred strategies of behavior during conflict in accordance with the methods of Kenneth Thomas. Statistical processing of psychodiagnostic data included dispersive (ANOVA) and discriminative analyses. Results. This study found significant differences in the parameters of evoked brain activity components in responses to emotionally charged stimuli (“aggression”, “positive”, “tolerance”, “extremism, terrorism”) compared with neutral images. Student’s t-test (Holms- corrected for multiple comparisons) was used to analyze the EEG-VEP data. Conclusion. This study confirmed the hypothesis of differences in spatio-temporal and amplitude parameters of evoked brain potentials in young men exhibiting differing levels of aggressiveness. The sources of evoked brain activity determined using sLORETA (Standardized Low-resolution Brain Electromagnetic Tomography) were different between carriers of different genotypes

Psychological and Genetic Differences Among Representatives of Various Ethnic Groups Living in South Russia

Introduction. This paper (a) presents the study of psychological differences in manifestations of aggressive attitudes and personal characteristics among representatives of various ethnic groups living in South Russia and (b) concentrates on genetic differences in the COMT Val158Met polymorphism within the study sample. This is the first study that (a) has assessed manifestations of aggressive attitudes and personal characteristics in healthy representatives of various ethnic groups with different COMT genotypes and (b) has offered normative data for the Wagner Hand Test obtained from an investigation in a sample of South Russian individual participants. Methods. The study used the following techniques: (a) the Spielberger–Hanin anxiety test, (b) the questionnaire of formal-dynamic characteristics of personality by Rusalov, and (c) the Wagner Hand Test (in Kurbatova’s modification). Genetic analysis included the method for DNA extraction from buccal epithelial cells and the polymerase chain reaction (PCR) method. The psychological study involved university students (n = 163; mean age, 18.9 years); the psychogenetic study involved residents of Crimea (n = 76; 57 women and 19 men). Results. The representatives of Russian and Tatar ethnic groups with the Met/Met COMT genotype had significantly higher total scores of aggression and direction, higher level of trait anxiety, and low motor ergicity. Tatar girls from the Val/Val COMT genotype group had high scores in the exhibitionism scale. The Val/Met COMT genotype in Russian girls was associated with manifestations of tension (anxiety) and ‘pathology’ as a total index of ‘personal maladjustment’ and the ‘tendency to escape from reality’. Discussion. The obtained results can be applied to the practice of individualized socio-pedagogical impacts on representatives of various ethnic groups with the genotypes associated with maladaptive personality traits