Kenneth Sandnabba

Validity of a Test of Children's Suggestibility for Predicting Responses to Two Interview Situations Differing in Their Degree of Suggestiveness.

In the present study the relative contributions of internal and external sources of variation in childrens suggestibility in interrogative situations were examined. One hundred and eleven children (48 4- to 5-year-olds and 63 7- to 8-year-olds) were administered a suggestibility test (BTSS) and the most suggestible (N=36) and the least suggestible (N=36) children were randomly assigned to either an interview condition containing several suggestive techniques or to one containing only suggestive questions. The effects of internal sources of variation in suggestibility were compared with the effects of the interview styles on the childrens answers. The former did influence the children, but the external sources of variation in suggestibility had a stronger impact. Influences of cognitive, developmental factors could be found, but not when abuse-related questions were asked and high pressured interview methods were used. These findings indicate that individual assessment of suggestibility can be of some assistance when interviewing children, but diminishing suggestive influences in interrogations must be given priority.

Alcohol and aggressive behavior in men--moderating effects of oxytocin receptor gene (OXTR) polymorphisms.

We explored if the disposition to react with aggression while alcohol intoxicated was moderated by polymorphic variants of the oxytocin receptor gene (OXTR). Twelve OXTR polymorphisms were genotyped in 116 Finnish men [aged 18–30, M = 22.7, standard deviation (SD) = 2.4] who were randomly assigned to an alcohol condition in which they received an alcohol dose of 0.7 g pure ethanol/kg body weight or a placebo condition. Aggressive behavior was measured using a laboratory paradigm in which it was operationalized as the level of aversive noise administered to a fictive opponent. No main effects of the polymorphisms on aggressive behavior were found after controlling for multiple testing. The interactive effects between alcohol and two of the OXTR polymorphisms (rs4564970 and rs1488467) on aggressive behavior were nominally significant and remained significant for the rs4564970 when controlled for multiple tests. To the best of our knowledge, this is the first experimental study suggesting interactive effects of specific genetic variants and alcohol on aggressive behavior in humans.

Indicators of premature ejaculation and their associations with sexual distress in a population-based sample of young twins and their siblings.

INTRODUCTION Recently, in anticipation of the Diagnostic and Statistical Manual of Mental Disorders V, much consideration has been given to the diagnostic criteria for premature ejaculation (PE). The scientific community is yet to agree not only on the etiology of PE, but also on the most suitable diagnosis and forms of treatment. It has been suggested that the diagnostic criteria of PE should be strictly empirical and rely on intravaginal latency time alone, whereas others stress the need to also include psychological and personal factors. AIM To examine different indicators of PE and their relationship with and ability to predict sexual distress. MAIN OUTCOME MEASURES Statistical analyses of data on sexual distress and different measures of ejaculatory function on a population-based sample of 3,332 Finnish men. METHODS The present study involved a population-based sample of 3,332 males, of which 2,328 were twins aged 18-33, and 1,004 were over 18-year-old siblings to the aforementioned (M = 26.17 years of age). The individual contributions of different PE-indicator variables to experienced sexual distress were investigated by calculating correlations and performing a regression analysis. RESULTS All included indicators of PE were significantly associated with sexual distress, and significant and logical differences in sexual distress were found between intravariable levels for several of the indicator variables. Only variables relating to subjective experience (e.g., worrying about PE) were uniquely related to sexual distress when other indicators were controlled for. CONCLUSIONS The results suggest that variables measuring subjective experience may be useful when considering diagnostic criteria if indicators that are related to sexual distress are considered useful. However, overall, the association between PE and sexual distress is not especially strong, emphasizing the fact that more objective indicators of PE may not necessarily be associated with significant distress.

Associations between oxytocin receptor gene (OXTR) polymorphisms and self-reported aggressive behavior and anger: Interactions with alcohol consumption

Oxytocin has been implicated in the regulation of social as well as aggressive behaviors, and in a recent study we found that the effect of alcohol on aggressive behavior was moderated by the individuals genotype on an oxytocin receptor gene (OXTR) polymorphism (Johansson et al., 2012). In this study we wanted to deepen and expand the analysis by exploring associations between three (rs1488467, rs4564970, rs1042778) OXTR polymorphisms and aggressive behavior, trait anger as well as anger control in a population-based sample of Finnish men and women (N=3577) aged between 18 and 49 years (M=26.45 years, SD=5.02). A specific aim was to investigate if the polymorphisms would show interactive effects with alcohol consumption on aggressive behavior and trait anger, as well as to explore whether these polymorphisms affect differences in anger control between self-reported sober and intoxicated states. The results showed no main effects of the polymorphisms, however, three interactions between the polymorphisms and alcohol consumption were found. The effect of alcohol consumption on aggressive behavior was moderated by the genotype of the individual on the rs4564970 polymorphism, in line with previous results (Johansson et al., 2012). For trait anger, both the rs1488467 and the rs4564970 polymorphisms interacted with alcohol consumption. It appears that the region of the OXTR gene including both the rs4564970 and the rs1488467 polymorphisms may be involved in the regulation of the relationship between alcohol and aggressive behavior as well as between alcohol and the propensity to react to situations with elevated levels of anger.

A Study of Possible Associations Between Single Nucleotide Polymorphisms in the Serotonin Receptor 1A, 1B, and 2C Genes and Self‐Reported Ejaculation Latency Time

INTRODUCTION Previous research has indicated that serotonergic genes may influence ejaculatory function. Attempts to investigate effects of polymorphisms in serotonergic genes have been carried out, but so far, no study has conducted exploratory genotype analyses regarding the serotonin receptor 1A, 1B, and 2C subtypes, which have been hypothesized to mediate the inhibitory effects of serotonin on ejaculation in rodents. AIM The aim of the present study was to investigate effects of a total of six single nucleotide polymorphisms (SNPs) located in genes encoding serotonin receptor subtypes 1A, 1B, and 2C on self-reported ejaculation latency time. METHODS A retrospective self-report measure of ejaculation latency time was used to investigate ejaculatory function in a population-based sample of 1,399 male twins. DNA was collected using self-administered saliva sampling. MAIN OUTCOME MEASURE Calculations of allelic effects were conducted using the Generalized Estimating Equations module of PASW 18.0, which appropriately controls for between-subjects dependence. RESULTS Out of six investigated polymorphisms, two SNPs (both serotonin receptor 5-HT(1B) linked) had a significant main effect on ejaculation latency time. Of these, one (rs11568817) remained significant after Bonferroni correction for multiple testing, indicating that individuals homozygous for the G allele had significantly shorter ejaculation latencies. CONCLUSIONS The results of this study support the hypothesis that serotonergic genes play a role in ejaculatory function in the general population. Replication of the results of the present study is warranted.

Retrospective reports of parental physical affection and parenting style: a study of Finnish twins.

Individual differences in parenting behaviors are due, in part, to genetic factors. In the present study, the authors sought to determine whether the degree of genetic influence varied according to the type of parental behavior under consideration. A population-based sample of 2,334 pairs of Finnish twins provided ratings on the physical affection, control, abusiveness, and indifference shown by their father and mother during childhood. Genetic influences, shared environmental influences, and nonshared environmental influences accounted for a small-to-medium proportion (17%-30%), a small-to-large proportion (22%-44%), and a medium-to-large proportion (37%-55%) of the variance in each parenting measure, respectively. There were no significant differences in effect sizes for mothers and fathers or across the 4 types of parental behavior. The genetic results may reflect characteristic styles with which parents respond to genetically influenced behaviors of individuals (gene-environment correlations) or individual perceptions of this relationship (gene-person correlation processes). The findings have implications for intervention and prevention work with families and for interpretation of evidence for interactions between genes and parenting behaviors.

Genes and gene networks implicated in aggression related behaviour

Aggressive behaviour is a major cause of mortality and morbidity. Despite of moderate heritability estimates, progress in identifying the genetic factors underlying aggressive behaviour has been limited. There are currently three genetic mouse models of high and low aggression created using selective breeding. This is the first study to offer a global transcriptomic characterization of the prefrontal cortex across all three genetic mouse models of aggression. A systems biology approach has been applied to transcriptomic data across the three pairs of selected inbred mouse strains (Turku Aggressive (TA) and Turku Non-Aggressive (TNA), Short Attack Latency (SAL) and Long Attack Latency (LAL) mice and North Carolina Aggressive (NC900) and North Carolina Non-Aggressive (NC100)), providing novel insight into the neurobiological mechanisms and genetics underlying aggression. First, weighted gene co-expression network analysis (WGCNA) was performed to identify modules of highly correlated genes associated with aggression. Probe sets belonging to gene modules uncovered by WGCNA were carried forward for network analysis using ingenuity pathway analysis (IPA). The RankProd non-parametric algorithm was then used to statistically evaluate expression differences across the genes belonging to modules significantly associated with aggression. IPA uncovered two pathways, involving NF-kB and MAPKs. The secondary RankProd analysis yielded 14 differentially expressed genes, some of which have previously been implicated in pathways associated with aggressive behaviour, such as Adrbk2. The results highlighted plausible candidate genes and gene networks implicated in aggression-related behaviour.

Subjectively Measured Ejaculation Latency Time and Its Association with Different Sexual Activities while Controlling for Age and Relationship Length

INTRODUCTION Recently, attempts to formulate valid and suitable definitions for (different subcategories of) premature ejaculation have resulted in substantial progress in the pursuit to gain knowledge about ejaculatory function. However, the association between ejaculatory dysfunction and different types of sexual activities has yet to be thoroughly investigated, and (due to conflicting results between studies) the potential effects of age and relationship length still need to be taken into account. AIM The aim of this study is to investigate the associations of age, relationship length, frequency of different sexual activities, and different modes of achieving ejaculation with self-reported ejaculation latency time. MAIN OUTCOME MEASURES The main outcome is establishing associations between age, relationship length, self-reported ejaculation latency time, and frequency of different kinds of sexual activities and different modes of achieving ejaculation (such as achieving ejaculation through oral or vaginal sex). METHODS Statistical analyses of data on age, relationship length, self-reported ejaculation latency time, and frequency of different sexual activities and different modes of achieving ejaculation were conducted on a population-based sample of 3,189 males aged 18-48 years (mean = 29.9 years, standard deviation = 6.94). RESULTS Age and relationship length were significantly negatively associated with self-reported ejaculation latency time. Frequency of different kinds of sexual behavior generally had a positive association with self-reported ejaculation latency time, as had different modes of achieving ejaculation. CONCLUSIONS The findings highlight the need for more extensive studies on and increased knowledge of different aspects of ejaculatory function before a valid and suitable definition for premature ejaculation can be formulated.

Transcriptome analysis of genes and gene networks involved in aggressive behavior in mouse and zebrafish

Despite moderate heritability estimates, the molecular architecture of aggressive behavior remains poorly characterized. This study compared gene expression profiles from a genetic mouse model of aggression with zebrafish, an animal model traditionally used to study aggression. A meta‐analytic, cross‐species approach was used to identify genomic variants associated with aggressive behavior. The Rankprod algorithm was used to evaluated mRNA differences from prefrontal cortex tissues of three sets of mouse lines (N = 18) selectively bred for low and high aggressive behavior (SAL/LAL, TA/TNA, and NC900/NC100). The same approach was used to evaluate mRNA differences in zebrafish (N = 12) exposed to aggressive or non‐aggressive social encounters. Results were compared to uncover genes consistently implicated in aggression across both studies. Seventy‐six genes were differentially expressed (PFP < 0.05) in aggressive compared to non‐aggressive mice. Seventy genes were differentially expressed in zebrafish exposed to a fight encounter compared to isolated zebrafish. Seven genes (Fos, Dusp1, Hdac4, Ier2, Bdnf, Btg2, and Nr4a1) were differentially expressed across both species 5 of which belonging to a gene‐network centred on the c‐Fos gene hub. Network analysis revealed an association with the MAPK signaling cascade. In human studies HDAC4 haploinsufficiency is a key genetic mechanism associated with brachydactyly mental retardation syndrome (BDMR), which is associated with aggressive behaviors. Moreover, the HDAC4 receptor is a drug target for valproic acid, which is being employed as an effective pharmacological treatment for aggressive behavior in geriatric, psychiatric, and brain‐injury patients.

Are Early and Current Erectile Problems Associated With Anxiety and Depression in Young Men? A Retrospective Self-Report Study

Erectile dysfunction (ED) has been extensively studied in the past few decades, and significant advances have been made in understanding its etiology. Most cases of this type of dysfunction have an organic etiology, and ED occurs primarily in older men. However, relatively little is known about erectile problems in young men or about the interconnection between psychiatric symptoms and ED etiology. In this study, the authors investigated ED symptoms in a large, population-based sample of 18–48-year-old men. Participants reported ED symptoms from their first intercourse experience as well as those occurring at present. The authors assessed the association between reported ED symptoms during early partnered sexual experiences and present ED symptoms. Furthermore, the authors investigated associations between age, symptoms of anxiety and depression, and erectile problems. Results indicated that age was a significant predictor of ED problems already in young age groups. ED problems were prevalent to a much higher extent during early sexual intercourse experiences and appeared to pass with time for most men. Anxiety and depression were significant predictors of present erectile problems. Implications of the results and potential limitations were discussed.