Patrick Jern

• Professor
• Professor of Applied Psychology at Åbo Akademi University

Johdanto: HEXACO-PI-R mittaa persoonallisuuden vaihtelua kuudella persoonallisuuden pääulottuvuudella sekä näihin latautuvilla 24:llä ala-asteikolla. Testin komponenttirakenne on todennettu testin käännösversioilla tehdyissä tutkimuksissa. Tässä tutkimuksessa tarkastelimme suomennetun testin psykometrisiä ominaisuuksia ja komponenttirakennetta suur...

Sexual compliance (i.e., consenting to sexual activity despite the lack of initial desire for it) is common in committed relationships. Previous research has shown that sexual compliance can have both positive and negative consequences for the well-being of the individual and the relationship. The aim of the present study was to develop a scale to...

Sexual compliance (i.e., consensually engaging in sex despite a lack of desire for it) is common in committed intimate relationships, but the consequences of compliance for the well-being of the individual and the relationship are poorly understood. We investigated the perceived consequences of sexual compliance and perceptions of factors contribut...

It has been proposed that psychedelics promote wellbeing through spiritual-type transformations, involving changes in metaphysical beliefs. Past empirical research shows a link between the use of psychedelics and the endorsement of non-physicalist metaphysical beliefs. However, non-physicalist beliefs encompass a wide range of metaphysical ideas, a...

Most Five-Factor Model (FFM) questionnaire items contain unique variance that is partly heritable, stable, and consensually observable, demonstrates consistent associations with age and sex, and predicts life outcomes beyond higher order factors. Extending these findings to the HEXACO model, we meta-analyzed single-item cross-rater agreement, herit...

The perceived consequences of sexual compliance, that is consensually engaging in partnered sexual activity despite a lack of sexual desire, remain underexplored. The current population-based study elucidates participants’ perceptions of compliance by asking their preference of either complying to sex with their current partner or experiencing a hy...

Sexual compliance (i.e., to consent to sexual activity despite the lack of initial desire for it) is common in committed relationships. Previous research has shown that sexual compliance can have both positive and negative consequences for the well-being of the individual and the relationship. The aim of the present study was to develop a scale to...

Background Physical exercise may alleviate premature ejaculation symptoms, a prevalent male sexual dysfunction linked to a series of negative outcomes for men and their partners. Objective We investigated the effectiveness of high-intensity interval training (HIIT) and slow breathing interventions on premature ejaculation symptoms and their relati...

Introduction Disgust is a basic emotion directed towards certain objects to avoid harm (Angyal, 1941), mainly pathogens. Research, however, has proposed a heterogeneity of disgust beyond pathogen avoidance to generate the functional model, which proposed the functionally distinct domains of disgust: moral, pathogen, and sexual. This model proposes...

It has been proposed that psychedelics promote wellbeing through spiritual-type transformations, involving changes in metaphysical beliefs. Past empirical research shows a link between the use of psychedelics and the endorsement of non-physicalist metaphysical beliefs. However, non-physicalist beliefs encompass a wide range of metaphysical ideas, a...

Current research indicates that aggressive sexual fantasies (ASF) are related to sexual aggression, above and beyond other risk factors for this behavior. There have, however, rarely been explicitly considered in multifactor models aiming to explain sexual aggression. One exception is the multifactorial Revised Confluence Model of Sexual Aggression...

Existing evidence indicates genetic and non-genetic influences on sexual orientation; however, the possibility of gene-environment interplay has not been previously formally tested despite theories indicating this. Using a Finnish twin cohort, this study investigated whether childhood gender nonconformity and early-life adversities independently mo...

Premature ejaculation and erectile dysfunction are common male sexual dysfunctions worldwide, causing substantial distress in men as well as their partners and decreasing the quality and stability of romantic relationships. We investigated the associations between the self-reported anatomical characteristics of penises and sexual dysfunctions in an...

Sexual dysfunction, a globally widespread concern, is associated with numerous negative outcomes. While some evidence indicates the potential of ginger supplementation to enhance sexual function, comprehensive research in this area remains scarce and the potential mechanism behind is unclear. The current study aimed to explore if and how consumptio...

The endogenous μ-opioid receptor (MOR) system plays a key role in the mammalian reward circuit. Human and animal experiments suggest the involvement of MORs in human sexual pleasure, yet this hypothesis currently lacks in vivo support. Methods: We used PET with the radioligand [11C]carfentanil, which has high affinity for MORs, to quantify endogeno...

We investigated the prevalence of problematic masturbation using different criteria. We also investigated if masturbation-related distress was associated with sexual abuse history, family attitudes towards sexuality during childhood, and depression and anxiety symptoms. Here, 12,271 Finnish men and women completed a survey reporting masturbation fr...

Although many researchers have proposed that women will show stronger preferences for male facial masculinity when conception probability is high, empirical tests of this hypothesis have produced mixed results. One possible explanation for these inconsistent findings is that effects of conception probability on women’s preferences for facial mascul...

Premature ejaculation and erectile dysfunction are common male sexual dysfunctions worldwide, causing substantial distress in men as well as their partners and decrease the quality and stability of romantic relationships. We investigated the associations between self-reported anatomical characteristics of the penis and sexual dysfunctions in an urb...

Background: Premature ejaculation (PE), which leads to substantial distress in men and their partners, is a common male sexual dysfunction worldwide. However, there is still a lack of effective treatments without side effects. Objectives: We investigated the effect of high-intensity interval training (HIIT) on PE symptoms. Materials and methods...

Sexual compliance (i.e., consensually engaging in sex despite a lack of desire for it) is common in committed intimate relationships, but the consequences of compliance for the well-being of the individual and the relationship are poorly understood. We investigated the perceived consequences of sexual compliance and possible factors contributing to...

The current study investigated the associations between sexually submissive and dominant behaviors and sexual dysfunction in Finnish men and women. We analyzed three population-based data sets from 2006, 2009, and 2021–2022, including 29,821 participants in total. Participants filled out a questionnaire about their sexually submissive and dominant...

Sexual problems are common complaints across countries and cultures, and behavioral immune system theory suggests disgust plays an essential role in sexual functioning. The current study investigated 1) if disgust induced by sexual body fluids would reduce sexual arousal, reduce the likelihood of sexual engagement, and enhance disgust toward subseq...

There is a lay assumption that women’s sexual desire varies substantially over time, whereas men’s is stable. This assumption is mirrored in prominent theories of desire, which posit that women are more variable than men in the extent to which they desire sex, and that women’s sexual desire is more contextually sensitive than men’s. We tested this...

Background Premature ejaculation (PE) is a common male sexual dysfunction worldwide. It leads to substantial distress in men and their partners, constitutes a serious threat to the quality and stability of romantic relationships, and results in a decreased quality of life in a large part of the population. Aim We investigated the prevalence of PE...

Sex is one of the most rewarding and motivating behaviours for humans. Endogenous mu-opioid receptor system (MORs) plays a key role in the mammalian reward circuit. Both human and animal experiments suggest the involvements of MORs in human sexual pleasure, yet this hypothesis currently lacks in vivo support. We used positron emission tomography (P...

Only one study has examined bidirectional causality between sexual minority status (having same-sex attraction) and psychological distress. We combined twin and genomic data from 8700 to 9700 participants in the UK Twins Early Development Study cohort at ≈21 years to replicate and extend these bidirectional causal effects using separate unidirectio...

Using paper surveys, we investigated sexual behaviors and desires of 181 inmates in a Finnish prison. Conjugal visits, sexual desire, and gender were the strongest predictors of sexual activity. Reports of coercive experiences were somewhat less prevalent than reported in international studies. Compared with population-based data, inmates reported...

Premature ejaculation (PE) and erectile dysfunction (ED), which is common male sexual dysfunctions worldwide, lead to substantial distress in men as well as their partners, and decrease the quality and stability of romantic relationships, and, consequently, lead to a decreased quality of life in a large part of the population. We investigated the a...

Although health disparities among same-sex attracted compared to heterosexual individuals are typically explained by minority stress, there is limited evidence for a causal effect. This study investigated whether same-sex attraction was causally associated with psychological distress and risky sexual behavior using sociosexual behavior as a proxy....

Substantial empirical evidence suggests that individuals who belong to sexual and gender minorities experience more anxiety and depression than heterosexual and cisgender people. Many previous studies have not, however, used population-based samples. There is also a shortage of evidence about certain sexual and gender minorities (e.g., nonbinary in...

Using paper surveys, we investigated sexual behaviors and desires of 181 inmates in a Finnish prison. Conjugal visits, sexual desire, and gender were the strongest predictors of sexual activity. Reports of coercive experiences were somewhat less prevalent compared to foreign studies. Compared with population-based data, prisoners reported fewer par...

Despite the substantial heritability of antisocial behavior (ASB), specific genetic variants robustly associated with the trait have not been identified. The present study by the Broad Antisocial Behavior Consortium (BroadABC) meta-analyzed data from 28 discovery samples (N = 85,359) and five independent replication samples (N = 8058) with genotypi...

Despite the substantial heritability of antisocial behavior (ASB), specific genetic variants robustly associated with the trait have not been identified. The present study by the Broad Antisocial Behavior Consortium (BroadABC) meta-analyzed data from 28 discovery samples (N = 85,359) and five independent replication samples (N = 8,058) with genotyp...

Although many researchers have proposed that women will show stronger preferences for male facial masculinity when conception probability is high, empirical tests of this hypothesis have produced mixed results. One possible explanation for these inconsistent findings is that effects of conception probability on women’s preferences for facial mascul...

Most Five-Factor Model questionnaire items contain unique variance that 1) is heritable, stable, and observable; 2) demonstrates consistent associations with age and sex, and 3) is predictive of life outcomes over and above higher-order factors. This is consistent with items indexing a unique level of the personality trait hierarchy—nuances. Extend...

Background Sexual and relationship satisfaction are intimately connected and share many predictors. Aim The aim of the present study is to disentangle the relationship between sexual and relationship satisfaction, by exploring the connections to other relevant correlates. Methods Regularized mixed graphical model networks were estimated separatel...

According to previous research, interest in BDSM (Bondage-Discipline, Dominance-Submission and Sadomasochism) activities is high in several European countries and various BDSM practices are not uncommon. There is a limited amount of research on the personalities of BDSM practitioners, but in previous research practitioners have been found to have b...

Objectives: Risky sexual behavior among sexual minorities (lesbian, gay, and bisexual individuals) are partly attributed to mental health and other social disparities; but this may be confounded by correlated genetic and environmental influences. As preregistered, the present study investigated indirect associations between sexual minority status a...

The endogenous mu-opioid receptor (MOR) system modulates a multitude of social and reward-related functions, and exogenous opiates also influence sex drive in humans and animals. Sex drive shows substantial variation across humans, and it is possible that individual differences in MOR availability underlie interindividual of variation in human sex...

The endogenous mu-opioid receptor (MOR) system modulates a multitude of social and reward-related functions, and exogenous opiates also influence sex drive in humans and animals. Sex drive shows substantial variation across humans, and it is possible that individual differences in MOR availability underlie interindividual of variation in human sex...

Over the past decade, evolutionary psychologists have proposed that many moral stances function to promote self-interests. At the same time, behavioral geneticists have demonstrated that many moral stances have genetic bases. We integrated these perspectives by examining how moral condemnation of recreational drug use relates to sexual strategy (i....

Background Evidence indicates that minority stress does not sufficiently explain mental health disparities in non-heterosexual compared to heterosexual individuals. We investigated alternative mechanisms whereby childhood factors (childhood gender nonconformity, early-life adversities and parent-child interactions) moderate the relationships betwee...

People vary in the degree to which they enjoy eating meats versus plants. This paper examines the genetic and environmental roots of this variation, as well as the genetic and environmental roots of meat neophobia, plant neophobia, and vegetarianism/veganism. Using data from 9,319 adult Finnish twins and siblings of twins (551 MZ, 861 DZ complete;...

People vary in the degree to which they enjoy eating meats versus plants. This paper examines the genetic and environmental roots of this variation, as well as the genetic and environmental roots of meat neophobia, plant neophobia, and vegetarianism/veganism. Using data from 9,319 adult Finnish twins and siblings of twins (551 MZ, 861 DZ complete;...

Premature ejaculation (PE) is a common sexual complaint among men, but its etiology is poorly understood. Previous studies on the dual control model of sexuality has revealed that propensities for sexual excitation and inhibition can contribute to sexual dysfunctions, but few studies have included a measure of premature ejaculation. We sought to ex...

Research on romantic jealousy has traditionally focused on sex differences. We investigated why individuals vary in romantic jealousy, even within the sexes, using a genetically informed design of ~7700 Finnish twins and their siblings. First, we estimated genetic, shared environmental and nonshared environmental influences on jealousy, Second, we...

Kaskikallio, A., Jern, P., & Westerlund, M. (2021). HEXACO-PI-R-persoonallisuuskyselyn suomenkielisen version psykometriset ominaisuudet: komponenttirakenne ja reliabiliteetit. Psykologia, 56(03).

Existing work indicates that socio-political attitudes (or: ideology) are associated with personality, with Social Dominance Orientation and Right-Wing Authoritarianism relating most strongly to honesty-humility and openness to experience, the two value-related domains of the HEXACO framework. Using a sample of 7067 twins and siblings of twins (inc...

Over the past decade, evolutionary psychologists have proposed that many moral stances function to promote self-interests, and behavioral geneticists have demonstrated that many moral stances have genetic bases. We integrate these perspectives by examining how moral condemnation of recreational drug use relates to sexual strategy (i.e., being more...

Background The association between erectile dysfunction (ED), free testosterone (T), and androgenic genetic polymorphisms is still unclear. As most studies in the field have focused on older (>40 y.o.) men, data from young men is scarce. In addition, the clinically observed comorbidity between ED and premature ejaculation (PE) has not been explaine...

Increased risky sexual behavior in sexual minorities relative to heterosexual individuals may be partly explained by mental health disparities, and both factors may be further jointly influenced by common genetic and environmental factors. However, these relationships have not been previously investigated. The objectives of the present study were t...

Decades of research have shown that about half of individual differences in personality traits is heritable. Recent studies have reported that heritability is not fixed, but instead decreases across the life span. However, findings are inconsistent and it is yet unclear whether these trends are because of a waning importance of heritable tendencies...

Dozens of studies have indicated that individuals more prone to experiencing disgust have stronger symptoms of anxiety disorders—especially contamination sensitivity. However, no work has informed the degree to which this relationship arises from genetic factors versus environmental factors. In the present study, we fill this gap by measuring disgu...

Understanding the mechanisms behind aggressive behavior (AGG) is vital so that effective prevention and intervention strategies can be developed. Maltreated children are hypothesized to be prone to social information processing biases, such as hostile attribution bias (HAB), which, in turn, may increase the likelihood of behaving aggressively. The...

Premature ejaculation (PE) is associated with decreased quality of life, lower confidence and self-esteem, and higher levels of depression, anxiety, and interpersonal difficulties. Here we investigated the effectiveness of vibrator-assisted start-stop exercises for treatment of PE, and whether the treatment effect could be enhanced by an additional...

Purpose – Crime linkage analysis (CLA) can be applied in the police investigation-phase to sift through a database to find behaviorally similar cases to the one under investigation and in the trial-phase to try to prove that the perpetrator of two or more offences is the same, by showing similarity and distinctiveness in the offences. Lately, resea...

The present study investigated how women's sexual functioning and relationship satisfaction are associated with their partner's premature ejaculation (PE) symptoms, and whether prevalence rates of PE differ when women report on their male partners compared to male self-report. The sample comprised of responses from 1,779 Finnish women (mean age 33....

We evaluated two treatment conditions for low sexual desire in women: one where participants were administered a mindfulness-based treatment protocol and another with exercises focusing on scheduled sex and motivations for sex in addition to the aforementioned protocol. Seventy women (Mage 39.2, SD = 9.8) with complaints of low sexual desire were r...

Abstract Problems related to low sexual desire in women are common clinical complaints, and the aetiology is poorly understood. We investigated predictors of change in levels of sexual desire using a novel network approach, which assumes that mental disorders arise from direct interactions between symptoms. Using population-based data from 1,449 Fi...

Psychopathy is characterized by callous affect, interpersonal manipulation, a deviant lifestyle, and antisocial behavior. Previous research has linked psychopathic traits to childhood trauma, but also to the upstream variable number tandem repeat (uVNTR) polymorphism of the monoamine oxidase A (MAOA) gene. An interaction between childhood trauma an...

The objective of the study was to develop the methodology of behavioral crime linkage towards an applicable tool for the police to be used in homicide investigations. Thus far behavioral crime linkage studies on homicide have used datasets consisting exclusively of serial homicides. The present study, therefore, included hard-to-solve one-off offen...

The aim of the present study was to investigate how women’s tendency to pretend orgasm during intercourse is associated with orgasm function and intercourse-related pain, using a longitudinal design where temporal stability and possible causal relationships could be modeled. The study sample consisted of 1421 Finnish women who had participated in l...

A number of recent studies have implicated that incongruent use of hormonal contraceptives (HCs) negatively affects various aspects of women's romantic relationships. It has been suggested that women with incongruent HC use (a discrepancy in HC use status between when they first met their current partner and the time of study participation) report...

Background: Studies have suggested that dopamine plays a role in the neurobiological mechanism that triggers ejaculation, leading scientists to hypothesize that dopamine-related genetic polymorphisms could contribute to symptoms of premature ejaculation (PE). Aim: To investigate associations between dopamine receptor and catechol-O-methyltransfera...

Serotonin has long been implicated in the regulation of the processes that trigger the ejaculatory reflex. Most evidence of serotonergic involvement is, however, indirect, stemming either from studies on rodents or clinical trials investigating effects of serotonergic drugs. In the past decade, emerging evidence for heritability (i.e., genetic effe...

Using a sample of 757 British individuals, Pearce et al. (1) tested 24 single-nucleotide polymorphisms (SNPs) in six candidate genes for association with eight social behavior traits. For each SNP for each trait, five geno-typic model tests were reported (except the androgen receptor gene, for which two model tests were reported), resulting in 936...

Childhood maltreatment increases the risk of subsequent depression, anxiety and alcohol abuse, but the rate of resilient victims is unknown. Here, we investigated the rate of victims that do not suffer from clinical levels of these problems after severe maltreatment in a population-based sample of 10980 adult participants. Compared to men, women re...

SPSS sheet containing severe experiences of childhood maltreatment and depression, anxiety and alcohol abuse data. Please refer to the SPSS variable list for variable descriptions. (SAV)

Pheromones regulate social and reproductive behavior in most mammalian species. These effects are mediated by the vomeronasal and main olfactory systems. Effects of putative pheromones on human neuroendocrine activity, brain activity and attractiveness ratings suggest that humans may communicate via similar chemosignaling. Here we studied two sampl...

Premature ejaculation (PE) is one of the most common male sexual complaints, but its etiology is unclear. Psychological problems, such as symptoms of anxiety and depression, have traditionally been seen as causal or maintaining etiological components of PE, and previous cross-sectional studies have found weak positive associations between them. The...

Background Most studies examining female sexual functions (FSFs) have used cross-sectional designs, not allowing for studying temporal stability and possible relationships between different FSFs over time. Our aim was to study these relationships using a longitudinal approach. Method The study sample consisted of 2173 Finnish women from two large-...

Introduction: Premature ejaculation (PE) is a common sexual problem in men, but its etiology remains uncertain. Lifestyle factors have long been hypothesized to be associated with sexual problems in general and have been proposed as risk factors for PE. Aim: To explore associations among physical exercise, alcohol use, body mass index, PE, and e...

Nausea and vomiting during pregnancy (NVP) affects about 70 % of all expectant mothers and commonly impacts their physical health and psychosocial functioning. The aim of this study was to estimate the heritability of the presence, duration and severity of NVP. The sample consisted of 1723 women (M age = 41.78, SD = 11.67) including twins in both c...

Objective: To examine associations between symptoms of premature ejaculation and erectile dysfunction and the lifestyle factors alcohol use and physical exercise. Design and Method: An invitation to an online survey was sent out to a population-based sample of Finnish twins and siblings of twins in 2012. Of the 2559 individuals invited, 1054 respon...

Objective: Female sexual dysfunctions (FSDs; difficulties related to sexual desire, arousal, orgasm, and pain) are prevalent and associated with both relationship quality and overall wellbeing. Psychobehavioral interventions are widely used to treat FSDs; however, little is known about the effectiveness of these interventions. Our objective was to...

Table S1 Associations between investigated SNPs, AUDIT scores and smoking.

Why was the cohort consortium set up? Nausea and vomiting during pregnancy (NVP), commonly known as morning sickness, is very common and is typically self-limiting. However, more severe forms and the development of hyperemesis gravidarum (HG), defined as persistent and excessive vomiting, with dehydration, keto-nuria and >5% bodyweight loss, 1 may...

Premature ejaculation (PE) is divided into acquired and lifelong subtypes, with the implication that the latter is chronic. This longitudinal study included data for untreated respondents from a population-based sample (sample 1) and a sample of patients diagnosed with lifelong PE (sample 2). About half of the respondents who at time 1 fulfilled th...

Response sensitivity to common disgust elicitors varies considerably among individuals. The sources of these individual differences are largely unknown. In the current study, we use a large sample of female identical and nonidentical twins (N = 1,041 individuals) and their siblings (N = 170) to estimate the proportion of variation due to genetic ef...

Women's preferences for masculine versus feminine male faces are highly variable. According to a dominant theory in evolutionary psychology, this variability results from adaptations that optimize preferences by calibrating them to certain contextual factors, including women's self-perceived attractiveness, short- versus long-term relationship orie...

The multifaceted gut-brain peptide ghrelin and its receptor (GHSR-1a) are implicated in mechanisms regulating not only the energy balance but also the reward circuitry. In our pre-clinical models, we have shown that ghrelin increases whereas GHSR-1a antagonists decrease alcohol consumption and the motivation to consume alcohol in rodents. Moreover,...

Introduction: One of the never-ending debates in the developing field of sexual medicine is the extent to which genetics and experiences (i.e., "nature and nurture") contribute to sexuality. The debate continues despite the fact that these two sides have different abilities to create a scientific environment to support their cause. Contemporary ge...

Introduction Female sexual desire and arousal problems have been shown to have a heritable component of moderate size. Previous molecular genetic studies on sexual desire have mainly focused on genes associated with neurotransmitters such as dopamine and serotonin. Nevertheless, there is reason to believe that hormones with more specific functions...

The present study aimed to investigate prevalence of and reasons for selective serotonin reuptake inhibitor (SSRI) discontinuation, and compare the two most common SSRIs used in premature ejaculation (PE) treatment, in naturalistic settings (that is, outside clinical trials). The sample consisted of 132 Finnish men with a mean age of 42.5 years (s....

As in other socially monogamous species, pair-bonded humans commonly engage in sex with a partner other than their primary mate. For men, extrapair mating is straightforwardly explained from an adaptive perspective in terms of the reproductive benefits of multiple mates. For women, whose reproductive output is limited by their reproductive biology...

Alcohol intoxication, sexual arousal and negative emotional states have been found to precede certain sexual behaviors. Using data from an online self-report survey distributed to adults (N = 717; 423 men and 304 women), we compared adults with adult online sexual interactions (n = 640; 89.3%) to adults with interactions with a child or an adolesce...

IntroductionRecently, testosterone (T) has been shown to be associated with premature ejaculation (PE) symptoms in the literature. Furthermore, studies suggest that the etiology of PE is partly under genetic control.AimThe aim of this study was to reassess findings suggesting an association between testosterone (T) and a key symptom of PE, ejaculat...

There is a lack of knowledge about effects of behaviors during online sexual solicitations. Our aims were to explore the prevalence of identity deception and wanting to keep the interaction a secret, and how these behaviors relate to the outcome of sexual interactions online. The participants were adults who self-reported online sexual interactions...