Lara Cuevas

Incremental effect for antisocial personality disorder genetic risk combining 5-HTTLPR and 5-HTTVNTR polymorphisms

As the serotonin transporter gene (SLC6A4 or 5-HTT) is a key regulator of central serotonergic activity, several association studies between Antisocial Personality Disorder (APD) and the SLC6A4 polymorphisms have been conducted in the last decade. In the present study, the role of both 5-HTTLPR and 5-HTTVNTR polymorphisms of the SLC6A4 gene in APD is investigated. A sample of 147 male inmates was analyzed. APD was assessed by Alujas Antisocial Personality Disorder Scale, a measure that correlates 0.73 with the dimensional score of DSM-IV APD and 0.62 with factor II of the Psychopathy Checklist-Revised. Inmates presenting both 5-HTTLPR S/S+S/L and 5-HTTVNTR 12/12 had a higher risk of being classified in the APD group (Odds ratio=3.48). The results also showed that the genotype and haplotype distribution was more dissimilar when extreme groups were compared with odds ratios up to 6.50. Our results supported that, in addition to the widely investigated 5-HTTLPR polymorphism, the 5-HTTVNTR polymorphism might be an interesting candidate for association studies with APD. Results also suggested that previous failures to replicate the association between serotonin transporter gene polymorphisms and APD, or similar phenotypes, could have been due to an under-representation of extremely high APD subjects in the samples analyzed.

Is Openness to Experience an Independent Personality Dimension

The Openness to Experience personality dimension has been challenged for its lack of independence from other personality constructs. In order to test whether Openness is an independent trait, we applied the following psychometric tests to a sample of 1006 nonpsychology university students: NEO-PI-R, EPQ-RS, ZKPQ-III-R, and SSS-V. Results suggest that most of the Openness variance remains to be explained. Therefore, this domain can be considered independent within the personality area, although Extraversion and, above all, Sensation Seeking presented significant relationships with the Openness scales. Each NEO-PI-R Openness facet shows a different pattern of relationships with other personality constructs proposed by the Five-Fac- tor, Eysencks, and Zuckermans theories. Those relationships are discussed.

Testing the Indifferentiation Hypothesis during Childhood, Adolescence, and Adulthood.

The general (g) factor is the most general and relevant cognitive ability. This factor is considered to be one of the most important predictors of academic achievement and of many other socially relevant behavioral outcomes. In the last decades, many researchers have investigated the possible changes in the relevance of the g factor from childhood to adulthood. The indifferentiation hypothesis states that the variance attributed to the g factor and the main cognitive abilities will not change over the life span. In the present study, the authors tested that hypothesis in childhood, adolescence, and adulthood by using 2 different cognitive batteries (Test of Educational Ability [TEA; S. A. TEA, 1999], Wechsler Adult Intelligence Scales [WAIS; D. Wechsler, 1955]), which they administered in 2 different countries-Spain (TEA) and the United States (WAIS). The ages of the participants (N = 2,384) ranged from 8 to 54 years. Results showed that the number of factors extracted and the relevance were the same for every age group in both batteries, as predicted by the indifferentiation hypothesis. The authors discuss implications of intelligence assessment.

Exploratory and confirmatory factorial structure of the MCMI-III Personality Disorders: Overlapping versus non-overlapping scales

Background and Objectives: The aim of this study was to explore the factorial structure of the 14 Personality Disorder (PDs) scales of the MCMI-III for the overlapping and non-overlapping scales, independently. Previous exploratory studies using different factor extraction procedures inform that the structure of MCMI-III personality disorders has between 2 and 4 factors. Methods: The present study used a large sample of 674 non-clinical subjects divided at random in two groups: a) calibration, and b) validation. In the calibration group, principal component analysis with orthogonal rotation was carried out, obtaining 2, 3 and 4 factors for the overlapping and non-overlapping scales independently. In the validation group, the three models were compared using confirmatory factorial analysis techniques. Results and Conclusions: The exploratory and confirmatory results indicate that the 4-factor solution is the most plausible. Although the congruence coefficients between non-overlapping and overlapping scales in the 4-factor solution were higher, confirmatory factor analysis showed that models designed from overlapping scales did not fit well to data.