Gene-sex interaction in Hypercompetitive Attitude suggests beneficial effect of the DRD4 7-repeat allele in adaptation.

Twin studies provide evidence for the heritability of social attitudes, e.g. competitiveness, however, there are no psychogenetic association results linking competitive attitudes to genetic polymorphisms. Candidate gene studies report association with competitiveness-related phenotypes, risk taking for example was linked with the 7-repeat allele of the dopamine D4 receptor gene. This polymorphism has been studied extensively with novelty seeking and certain psychiatric disorders, as it plays a crucial role in molecular genetic mechanisms driving behavioral responses to the environment, especially modulating behavior through the reward circuitry. In the present study, we examined association of the DRD4 48-bp VNTR and competitiveness using self-report data from 399 non-related Caucasians. We found an interesting gene-sex interaction: 7-carrier males were more hypercompetitive as compared to non-carriers, while 7-carrier females were less hypercompetitive as compared to non-carriers. This finding remained significant after Bonferroni correction for multiple testing. Interestingly, among females we observed a significant positive correlation between hypercompetitiveness and mood characteristic variables, however, no such relationship could be detected in males. In 7-carrier females the association of hypercompetitiveness and anxiety or depression was more robust as compared to non-carrier females. These results highlight the importance of cultural influences in interpreting gene-sex interaction effects. Our results underlies interaction between genes and the environment; suggesting that the 7-repeat allele plays an important role in adaptivity, enabling sex-specific behavior to social expectations.

Individual differences in flow proneness are linked to a dopamine D2 receptor gene variant.

Flow is a special mental state characterized by deep concentration that occurs during the performance of optimally challenging tasks. In prior studies, proneness to experience flow has been found to be moderately heritable. In the present study, we investigated whether individual differences in flow proneness are related to a polymorphism of the dopamine D2 receptor coding gene (DRD2 C957T rs6277). This polymorphism affects striatal D2 receptor availability, a factor that has been shown to be related to flow proneness. To our knowledge, this is the first study to investigate the association between this trait and a specific gene variant. In a sample of 236 healthy Hungarian adults, we found that CC homozygotes report higher flow proneness than do T allele carriers, but only during mandatory activities (i.e., studying and working), not during leisure time. We discuss implications of this result, e.g., the potential mediators of the relationship.

A Genetic Variant (COMT) Coding Dopaminergic Activity Predicts Personality Traits in Healthy Elderly.

Association studies between the NEO five factor personality inventory and COMT rs4680 have focused on young adults and the results have been inconsistent. However, personality and cortical changes with age may put older adults in a more sensitive range for detecting a relationship. The present study examined associations of COMT rs4680 and personality in older adults. Genetic association analyses were carried out between the NEO and the targeted COMT rs4680 in a large, well-characterized sample of healthy, cognitively normal older adults (N = 616, mean age = 69.26 years). Three significant associations were found: participants with GG genotype showed lower mean scores on Neuroticism (p = 0.039) and higher scores on Agreeableness (p = 0.020) and Conscientiousness (p = 0.006) than participants with AA or AG genotypes. These results suggest that older adults with higher COMT enzymatic activity (GG), therefore lower dopamine level, have lower Neuroticism scores, and higher Agreeableness and Conscientiousness scores. This is consistent with a recent model of phasic and tonic dopamine release suggesting that even though GG genotype is associated with lower tonic dopamine release, the phasic release of dopamine might be optimal for a more adaptive personality profile.

[Neurocognitive endophenotypes in psychiatric genetics]. / Neurokognitív endofenotípusok a pszichiátriai genetikában.

Psychiatric genetics aims to map genetic factors of psychiatric disorders with complex inheritance. The most commonly used phenotype is the categorical variable of the presence or absence of a disease (case-control model). However, the biological background of various psychiatric disease categories often overlaps. Thus, the use of endophenotypes based on specific biological mechanisms seems to be a more efficient approach in genetic association studies. Results confirm that categorical variables as phenotypes are statistically not so sensitive in identification of a genetic association as well-chosen endophenotypes. Current literature advocates a growing significance of analyzing dimensional neurocognitive endophenotypes in genetic association studies, as well as in developing diagnostic category systems with biological backgrounds.

Lateral asymmetry of emotional arousal as a biomarker of attributional style during darts competitions.

According to the Multiple Arousal Theory, electrodermal activity (EDA) is not uniform across the body. However, the psychological meaning of a left or right-sided EDA dominance is still not clear. We explored EDA lateral asymmetry as a psychophysiological marker of optimistic and pessimistic attributional style regarding success and failure in a darts competition. Bilateral EDA pattern of 230 throws of a competing pair was measured by Obimon EDA including accelerometer measurements of movements. First, we confirmed that lateral asymmetry can be measured reliably based on EDA data from both wrists. Second, we assessed attributional styles related to lateral asymmetry based on 80 individual throws. We recorded participants' expectations regarding their upcoming performance, and their attribution of success and failure based on Seligman's definition as optimist (internal cause attributed to success, or external cause ascribed to failure) or pessimist. The ratio of optimist and pessimist attributions was significantly different for throws with right or left-sided EDA dominance (p = 0.001). Optimistic attribution characterized 84% of right dominant, while pessimist 63% of left-dominant EDA during throws. We replicated these findings on 50 throws from 10 more individuals (p = 0.034). All individuals were right-handed. We conclude that wrist EDA can be reliably measured during physical movements, such as in a darts game. Lateral EDA asymmetry is a consistent psychophysiological marker of the attitude toward success and failure in a competitive setting, suggesting that lateral asymmetry of emotional arousal may serve as a novel psychophysiological biomarker for attribution style. Results underlie the psychophysiological relevance of bilateral arousal assessment and provide evidence-based verification for the Multiple Arousal Theory.

[Association between mood characteristics and polymorphisms of glial cell line-derived neurotrophic factor (GNDF) in patients with depression]. / A hangulati dimenziók és a glia-eredetü növekedési faktort kódoló gén polimorfizmusainak összefüggése depresszióval diagnosztizált mintán.

Glial cell line-derived neurotrophic factor (GNDF) plays an important role in the development and synaptic plasticity of dopaminergic neurons, thus it could be an important therapeutic factor in Parkinson's disease. Results from candidate gene studies of GDNF in psychiatric disorders are contradictory. Moreover, the possible association between GDNF polymorphisms and major- or bipolar depression has not been studied to date. Recently, our research group has published an association between two GDNF polymorphisms (rs3812047, rs3096140) and the individual variability of anxiety measured by the Hospital Anxiety and Depression Scale (HADS) on a non-clinical sample. In the present study we further analyzed this association on a sample with major- and bipolar depression: we used data from 183 MDD, 116 BP, and 1172 control subjects and tested effect of GDNF rs3812047 and rs3096140 polymorphisms on mood disorders. The case control design did not show significant differences in the genotype distribution of BP or MDD versus control patients. However, in the bipolar group subjects with rs3812047 A allele showed a significantly higher anxiety and depression mean score then subjects with G allele (p=0.043). This result supports our previous findings demonstrated on a non-clinical sample. Interestingly we found an opposite effect of the rs3812047 using data from MDD patients: subjects with the G allele had higher depression scores (p=0.012). An interaction effect of patient subgroups and genetic variants of the rs3812047 was observed for both HADS subscales (anxiety: p=0.029; depression: 0.004). In summary, we confirmed the previously published association between the rs3812047 A allele and mood characteristics on the bipolar sample, and an effect in the opposite direction was detected in the patient group with major depression.

Selected rapporteur summaries from the XX World Congress of Psychiatric Genetics, Hamburg, Germany, October 14-18, 2012.

The XXth World Congress of Psychiatric Genetics (WCPG), sponsored by The International Society of Psychiatric Genetics (ISPG) took place in Hamburg, Germany on October 14-18, 2012. Approximately 600 participants gathered to discuss the latest findings in this rapidly advancing field. The following report was written by student travel awardees. Each was assigned sessions as rapporteurs. This manuscript represents topics covered in most, but not all, oral presentations during the conference, and some of the major notable new findings reported at this 2012 WCPG.

Severity of behavioral addiction symptoms among young adults using non-prescribed sedatives/hypnotics.

Introduction: Young adulthood is considered a critical period in terms of non-medical use of sedatives/hypnotics (NMUSH) as well as different types of behavioral addictions (BAs). However, the relationship between these behaviors has received scarce attention among young adult samples. Therefore, the aim of the present study was to investigate the association between NMUSH and symptoms of distinct BAs among young adults. Materials and methods: Analyses were conducted based on the data of two large sample studies (including a representative sample) carried out with young adult samples. The following BAs were assessed: problematic internet use, problematic video gaming, problematic social media use, problem gambling, exercise addiction, eating disorders, compulsive buying behavior, problematic mobile phone use, work addiction, and hair pulling. Symptoms of distinct BAs were analyzed in three groups formed based on the NMUSH: non-users, lifetime users, and current users. Results: The symptoms of problematic internet use, problematic social media use, problem gambling, exercise addiction, eating disorders, compulsive buying behavior and work addiction were significantly more severe among lifetime and/or current non-medical sedative and hypnotic users, compared to the non-user participants. The symptoms of problematic mobile phone use were the most severe in the non-user group. Conclusions: The results suggest co-occurrence between NMUSH and distinct BAs among young adults. These findings draw attention to the need for preventive interventions for this high-risk population.

[Changes in cognitive function in patients with diabetes mellitus]. / A kognitív funkciók változásai cukorbetegségben.

Patients with diabetes are approximately 1.5 times more likely to experience cognitive decline than individuals without diabetes mellitus. Most of the data suggest that patients with diabetes have reduced performance in numerous domains of cognitive function. In patients with type 1 diabetes, specific and global deficits involving speed of psychomotor efficiency, information processing, mental flexibility, attention, and visual perception seem to be present, while in patients with type 2 diabetes an increase in memory deficits, a reduction in psychomotor speed, and reduced frontal lobe (executive) functions have been found. The complex pathophysiology of changes in the central nervous system in diabetes has not yet been fully elucidated. It is important to consider the patient's age at the onset of diabetes, the glycemic control status, and the presence of diabetic complications. Neurological consequences of diabetes appear parallel to those observed in the aging brain. Neuroimaging studies highlight several structural cerebral changes, cortical and subcortical atrophy, beside increased leukoaraiosis that occurs in association with diabetes. There is supporting evidence from many hypotheses to explain the pathophysiology of cognitive decline associated with diabetes. The main hypotheses pointing to the potential, implied mechanisms involve hyperglycemia, hypoglycemia, microvascular disease, insulin resistance, hyperinsulinism, hyperphosphorylation of tau protein, and amyloid-ß deposition.

FOXN3 and GDNF Polymorphisms as Common Genetic Factors of Substance Use and Addictive Behaviors.

Epidemiological and phenomenological studies suggest shared underpinnings between multiple addictive behaviors. The present genetic association study was conducted as part of the Psychological and Genetic Factors of Addictions study (n = 3003) and aimed to investigate genetic overlaps between different substance use, addictive, and other compulsive behaviors. Association analyses targeted 32 single-nucleotide polymorphisms, potentially addictive substances (alcohol, tobacco, cannabis, and other drugs), and potentially addictive or compulsive behaviors (internet use, gaming, social networking site use, gambling, exercise, hair-pulling, and eating). Analyses revealed 29 nominally significant associations, from which, nine survived an FDRbl correction. Four associations were observed between FOXN3 rs759364 and potentially addictive behaviors: rs759364 showed an association with the frequency of alcohol consumption and mean scores of scales assessing internet addiction, gaming disorder, and exercise addiction. Significant associations were found between GDNF rs1549250, rs2973033, CNR1 rs806380, DRD2/ANKK1 rs1800497 variants, and the "lifetime other drugs" variable. These suggested that genetic factors may contribute similarly to specific substance use and addictive behaviors. Specifically, FOXN3 rs759364 and GDNF rs1549250 and rs2973033 may constitute genetic risk factors for multiple addictive behaviors. Due to limitations (e.g., convenience sampling, lack of structured scales for substance use), further studies are needed. Functional correlates and mechanisms underlying these relationships should also be investigated.

Development and validation of the Reward Deficiency Syndrome Questionnaire (RDSQ-29).

BACKGROUND: The reward deficiency syndrome (RDS) integrates psychological, neurological, and genetic factors of addictive, impulsive, and compulsive behaviors. However, to date, no instrument has been validated to assess the RDS construct. AIMS: The present study developed and tested a tool to assess RDS. METHODS: Data were collected on two college and university samples. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were performed on Sample 1 (N = 1726), and confirmatory analysis was conducted on an independent sample (N = 253). Impulsivity and sensation-seeking were assessed. RESULTS: Based on EFAs, a 29-item Reward Deficiency Syndrome Questionnaire (RDSQ-29) was developed, containing four subscales (lack of sexual satisfaction, activity, social concerns, and risk-seeking behavior). CFA indicated good fit (comparative fit index (CFI) = 0.941; Tucker-Lewis index (TLI) = 0.933; root mean square error of approximation (RMSEA) = 0.068). Construct validity analysis showed strong relationship between sensation-seeking and the RDS scale. CONCLUSION: The RDSQ-29 is an adequate scale assessing psychological and behavioral aspects of RDS. The RDSQ-29 assesses psychological and behavioral characteristics that may contribute to addictions generally.

Hungarian validation of the Buss-Perry Aggression Questionnaire-Is the short form more adequate?

OBJECTIVE: We aim to provide a publicly available Hungarian version of the BPAQ; compare the BPAQ factors to other personality traits; and compare both the original BPAQ factor structure provided by Buss and Perry (J. Pers. Soc. Psychol., 63, 1992, 452), the revised BPAQ-SF factor structure by Bryant and Smith (J. Res. Pers., 35, 2001, 138), and the BAQ by Webster et al. (Aggress. Behav., 40, 2014, 120). METHODS: The validation of the Hungarian version of the BPAQ was carried out on a Hungarian university sample (N = 841). There were three main focuses of data analysis: descriptive statistics, correlations, and confirmatory factor analyses. RESULTS: CFA-related statistics showed an adequate fit for the BPAQ 4 factors; however, contrary to prior validations of BPAQ, we were not able to clearly define the verbal aggression factor. We found that the shorter form of the BPAQ has a better model fit on our sample than the original form, while the model fit of the BAQ was in-between these. BPAQ scales showed low to moderate relationship with the Barratt Impulsivity Scale and Hospital Anxiety and Depression Scale. CONCLUSION: Both the BPAQ and the BPAQ-SF, also the BAQ provide acceptable model fitting on a Hungarian sample of university students. While most of BPAQ items provided adequate loadings on their hypothesized factors, two items (21 and 27) did not. We argue this is the result of conceptual inaccuracy of the original items.

Bilateral comparison of traditional and alternate electrodermal measurement sites.

Advances in mobile and wireless technology have expanded the scope of electrodermal research. Since traditional electrodermal measurement sites are not always suitable for laboratory research and are rarely appropriate for ambulatory measurements, there is a need to explore and contrast alternate measurement locations. We evaluated bilateral electrodermal activity (EDA) from five measurement sites (fingers, feet, wrists, shoulders, and calves). In a counterbalanced, randomized, within-subjects design study, participants (N = 115) engaged in a 4-min-long breathing exercise and were exposed to emotionally laden and neutral stimuli. High within-subject correlations were found between the EDA measured from fingers bilaterally (r = .89), between the left fingers and both feet (r = .72). Moderate correlations were found between EDA measured from the left fingers and wrists (r = .30 and r = .33), low correlations between the left fingers and the shoulders (r = -.03 and r = -.06) or calves (r = .05 and r = .14). Response latency was the shortest on the fingers while it was the longest on the lower body. Short response windows would miss some of the responses from the palmar surfaces and a substantial number from other evaluated locations. The fingers and the feet are the most reliable locations to measure from, followed by the wrists. We suggest setting site-specific response windows for different measurement locations. An investigation of repeatability showed that within-subject correlations, response frequencies, response amplitudes show a similar pattern from the first measurement time to a later one.

Co-occurrences of substance use and other potentially addictive behaviors: Epidemiological results from the Psychological and Genetic Factors of the Addictive Behaviors (PGA) Study.

BACKGROUND AND AIMS: Changes in the nomenclature of addictions suggest a significant shift in the conceptualization of addictions, where non-substance related behaviors can also be classified as addictions. A large amount of data provides empirical evidence that there are overlaps of different types of addictive behaviors in etiology, phenomenology, and in the underlying psychological and biological mechanisms. Our aim was to investigate the co-occurrences of a wide range of substance use and behavioral addictions. METHODS: The present epidemiological analysis was carried out as part of the Psychological and Genetic Factors of the Addictive Behaviors (PGA) Study, where data were collected from 3,003 adolescents and young adults (42.6% males; mean age 21 years). Addictions to psychoactive substances and behaviors were rigorously assessed. RESULTS: Data is provided on lifetime occurrences of the assessed substance uses, their co-occurrences, the prevalence estimates of specific behavioral addictions, and co-occurrences of different substance use and potentially addictive behaviors. Associations were found between (i) smoking and problematic Internet use, exercising, eating disorders, and gambling (ii) alcohol consumption and problematic Internet use, problematic online gaming, gambling, and eating disorders, and (iii) cannabis use and problematic online gaming and gambling. CONCLUSIONS: The results suggest a large overlap between the occurrence of these addictions and behaviors and underlies the importance of investigating the possible common psychological, genetic and neural pathways. These data further support concepts such as the Reward Deficiency Syndrome and the component model of addictions that propose a common phenomenological and etiological background of different addictive and related behaviors.

[Association between nicotine dependence and the -521 promoter polymorfism of the dopamine D4 receptor in patients with major depression]. / A nikotin dependencia és a dopamin D4-ES receptor -521 CT promoter polimorfizmusának asszociációja major depressziós betegcsoportban.

Investigating initiation of smoking behavior and factors involved in developing nicotine dependence is an important health issue worldwide. Various environmental, psychological and genetic risk factors are studies in the background of this complex behavior. The self-medication hypothesis may account for the increased prevalence of smoking behavior and more pronounced nicotine dependence among psychiatric patients. The present study investigates smoking habit and dependence measures in 133 Caucasian patients diagnosed with major depression. Investigated categorical endophenotypes included of smoking behavior included non-smokers who never smoked (1), non-smokers who smoked previously (2), occasional present smokers (3), and regular present smokers (4). Dimensional endophenotypes of nicotine addiction have been characterized by Hungarian adaptations of the Hooked on Nicotine Checklist and the Fagerström Test for Nicotine Dependence. Polymorphic regions of the dopaminergic system have been included as candidate genetic factors including the repeat polymorphism in the III. Exon of the DRD4 (DRD4 VNTR), two promoter SNPs of this gene (-521 CT and -616CG), as well as the repeat polymorphism of the dopamine transporter (DAT VNTR) polymorphism and the Val/Met polymorphism of the catechol-O-methyltransferase (COMT) gene. No significant difference was found between the genotype distributions in the four categories of smoking behavior. However, a significant association is reported with nicotine addiction of patients with major depression using the dimensional approach: patients with the C allele showed lower average scores on the Nicotine Checklist (CC or CT: mean score = 6.8 +/- 3.4) as compared to those without the C allele (IT: mean score = 10.l +/- 2.5), these differences were significant (p = 0.003).

Association of GDNF and CNTNAP2 gene variants with gambling.

BACKGROUND AND AIMS: Some form of gambling can be observed in nearly every society, as the gratification felt upon winning in uncertain conditions is universal. A culturally distinct form of gambling, associated with a traditional sporting event of archery known as "teer," is innate to the province of Meghalaya, India. The objective of this study was to find genetic variants underlying this unique form of behavioral addiction. To better understand game-based gambling, we studied genetic variants related to dopaminergic pathways and other genes previously linked to various psychological disorders. METHODS: This study was carried out on a sample of 196 Indo-Aryan adults from Shillong, Meghalaya. Genotyping of glial cell line-derived neurotrophic factor (GDNF) polymorphisms was carried out using real-time PCR. We further investigated 32 single nucleotide polymorphisms located in the 3' UTR of additional genes of interest using an OpenArray® real-time PCR platform. RESULTS: Case-control analysis revealed a significant association between GDNF variant rs2973033 (p = .00864, χ2 = 13.132, df = 2) and contactin-associated protein-like 2 (CNTNAP2) variant rs2530311 (p = .0448, χ2 = 13.132, df = 2) with gambling. DISCUSSION AND CONCLUSIONS: Association of the GDNF gene with gambling could be attributed to its involvement in the development and survival of dopaminergic neurons. Our result is in good agreement with previous data indicating the role of GDNF in certain substance addictions. Several rare variants in the CNTNAP2 gene were also implicated in alcohol addiction in a previous study. This pilot study provides further support for the role of GDNF and CNTNAP2 in addiction behaviors.

Association between anxiety and non-coding genetic variants of the galanin neuropeptide.

BACKGROUND: Galanin, an inhibitory neuropeptide and cotransmitter has long been known to co-localize with noradrenaline and serotonin in the central nervous system. Several human studies demonstrated altered galanin expression levels in major depressive disorder and anxiety. Pharmacological modulation of galanin signaling and transgenic strategies provide further proof for the involvement of the galanin system in the pathophysiology of mood disorders. Little is known, however, on the dynamic regulation of galanin expression at the transcriptional level. The aim of the present study was to seek genetic association of non-coding single nucleotide variations in the galanin gene with anxiety and depression. METHODS: Six single nucleotide polymorphisms (SNP) occurring either in the regulatory 5' or 3' flanking regions or within intronic sequences of the galanin gene have been genotyped with a high-throughput TaqMan OpenArray qPCR system in 526 healthy students (40% males). Depression and anxiety scores were obtained by filling in the Hospital Anxiety and Depression Scale (HADS) questionnaire. Data were analyzed by ANCOVA and Bonferroni correction was applied for multiple testing. Linkage disequilibrium (LD) analysis was used to map two haploblocks in the analyzed region. RESULTS AND CONCLUSIONS: A single-locus and a haplotype genetic association proved to be statistically significant. In single-marker analysis, the T allele of the rs1042577 SNP within the 3' untranslated region of the galanin gene associated with greater levels of anxiety (HADS scores were 7.05±4.0 vs 6.15±.15; p = 0.000407). Haplotype analysis revealed an association of the rs948854 C_rs4432027_C allele combination with anxiety [F(1,1046) = 4.140, p = 0.042141, η2 = 0.004, power = 0.529]. Neither of these associations turned out to be gender-specific. These promoter polymorphisms are supposed to participate in epigenetic regulation of galanin expression by creating potentially methylatable CpG dinucleotides. The functional importance of the rs1042577_T allele remains to be elucidated.

[Relationship between executive functions, body mass index and the DRD4 VNTR 7-repeat allele]. / A végrehajtó funkciók összefüggése a testtömegindexszel és a DRD4-VNTR 7-es alléllal.

Introduction and aim: Earlier results in the literature suggest that overweight subjects show weaker performance in executive function tasks as compared to normal weight people. Dopaminergic system is strongly linked to executive functions, body mass regulation and ingestion. The aim of the present study was to examine the possible relationship between DRD4 VNTR 7-repeat allele, body mass index and Stroop performance in a healthy adult population, and to draw psychogenetic conclusions. Method: 152 subjects without diabetic or psychiatric history participated in the study. Along with non-invasive DNA sampling, demographic, weight and height data were collected. The participants also solved the computerized Stroop task. 11 subjects belonged to the underweight (mean body mass index = 17.9 kg/m2), 98 subjects to the normal (mean body mass index = 21.8 kg/m2), and 43 subjects to the overweight (mean body mass index = 28.9 kg/m2) category. After grouping participants according to their body mass index and DRD4 VNTR genotype, we compared their mean performance to investigate the possible psychogenetic associations. Results: Body mass index and stimuli type showed significant interaction on error number (p = 0.045): subjects with normal body mass index made significantly less error as compared to under- and overweight subjects in incongruent trials. The 7-repeat allele carriers made tendentiously more errors than non-carriers. Normal weight people made less error - independently from their genotype -, while subjects with either low or high BMI carrying the 7-repeat allele made more errors compared to non-carriers. Conclusion: Under- and overweight subjects perform weaker where inhibition is necessary in the task. This may reflect their reactions to food-related situations. Orv Hetil. 2019; 160(39): 1554-1562.

Obimon: An open-source device enabling group measurement of electrodermal activity.

Electrodermal activity (EDA) provides the means to gauge the activity of the sympathetic nervous system. Assessment of EDA for research purposes requires measurement systems that are sensitive to small changes in arousal in the full measurement range, collecting, storing, and monitoring data. The objective behind designing a new open-source device was to be able to measure EDA simultaneously on many subjects, monitoring their activity in real time remotely and collecting high precision data suitable for analyses. To assure feasibility of simultaneous measurements on multiple subjects, the devices must be compact and wearable, without compromising data quality. Experiments were carried out using synchronized devices in group and single subject environments. Validity of EDA measurements of Obimon was demonstrated compared to a reference system (Nexus) during a breathing exercise, a short movie, and while exposed to loud computer-generated tones, using Pearson correlation, Passing-Bablok regression, and Bland-Altman analysis. Seamless management of several Obimons and real-time visualization of EDA via Android phone/tablet application from a large number of participants was demonstrated. Based on analyses of the data collected, we conclude that the Obimon device presented here is a valid and feasible tool for collecting EDA in single or multisubject environments.

The psychological and genetic factors of the addictive behaviors (PGA) study.

OBJECTIVES: Most of the addiction studies focus on very specific aspects of addictions, often with contradictory results, and integrated studies are quite rare. Experimental studies comparing underlying mechanisms of addictions and analyzing data from an integrative psychological and genetic perspective are almost nonexistent. The aim of the present paper is to describe the research protocol of the Psychological and Genetic Factors of Addictive Behaviors (PGA) study, which applies an integrative approach to understanding the acquisition, development, and maintenance of addictive behaviors. METHODS: A wide-spectrum national study was carried out. Data were collected from 3,003 adolescents. Addictions to both psychoactive substances and behaviors were thoroughly assessed via psychometrically robust scales, which also included assessment related to a wide range of related psychological dimensions. Additionally, a DNA sample was also collected from participants. RESULTS: The paper presents the detailed methodology of the PGA study. Data collection procedures, instrumentation, and the analytical approach used to attain the research objectives are described. CONCLUSIONS: Future plans, along with potential contributions of the PGA study, are also discussed. It is envisaged that the study will provide a unique opportunity to test possible mechanisms and causal pathways mediating the associations of genetic factors, psychological characteristics, and addictions.