1. Introduction

“Nobody’s born a psychopath” said Viding [1]. Psychopathy has been a significant topic for researchers from psychology, sociology, criminology, law and a variety of areas. In previous studies, some gender differences are pointed out in psychopathy, for example, Strand and Belfrage state in the study that there are a significant number of male psychopaths than female psychopaths [2]. However, as the wheels of the times continue to move forward, the number of female psychopaths is climbing up and some of them have the similar behavioral patterns as male psychopaths. This brings up the question: What causes the differences and changes in these numbers?

This study assume that maltreatment possibly affects the development of psychopathic traits in the male and female groups. Maltreatment has an influence on people developing empathy and increasing violent behaviors. Additionally, the maltreatment experienced by females and males is different. Therefore, maltreatment could have an impact on how males and females develop their psychopathic traits.

To think deep, what causes the differences in maltreatment? Social expectations can affect the behavioral patterns of females and males [3]. As we dig deeper into the field, social expectations can influence how males and females received maltreatment differently in early on their life and how females and males behave towards to maltreatment. Therefore, the assumption was put up those social expectations could be one of the most deep-seated reasons why there are gender differences in psychopathy. The study focusing on the social expectations is worth conducting. The goal of the proposed study is to test if social expectations play a role in the development of psychopathic traits in both male and female groups.

2. Gender differences and its factors

2.1. Gender differences in psychopathy

There are several gender differences found in psychopathy, even in PCL:SV. Research examining gender differences in response to the PCL:SV indicates that men and women differed in a number of ways at the item level [2]. Specifically, men scored higher than women on seven items: Superficial, Grandiose, Lacks Remorse, Lacks Empathy, Lacks Goals, Adolescent Antisocial Behavior, and Adult Antisocial Behavior, while women outperformed men on two items: Impulsive and Poor Behavioral Control [2].

Males and females had different associations with psychopathy and other kinds of antisocial behaviors. As for drug use, gender was found to be a mediator in the connection between Interpersonal-Affective Traits and the age at which drug usage began. Psychopathic personality features in women may have a greater impact on the initiation of drug use in girls. Women with a higher Impulsive-Antisocial Traits score were slightly more likely than males with a higher Impulsive-Antisocial Traits score to start using drugs at an earlier age. Interpersonal-Affective Traits was found to be more protective against early beginning into drug use in women than in men. Young women with strong Interpersonal-Affective Traits personality qualities, such as those who have a colder, less nurturing nature, may be less attached to peer groups and hence less prone to peer pressure including drugtaking activities [4].

Another example is aggressive behavior in adolescents. In the first place, despite the fact that girls scored lower in both CU (Callous-Unemotional) characteristics and proactive overt aggressiveness than boys, these traits only predicted proactive overt aggression in girls. Secondly, the Grandiose–Manipulative dimension was found to be stronger in boys than in girls when it came to proactive overt hostility [5]. Knowing what exact differences between male psychopaths and female psychopaths is the key to figuring out what factors causing the differences.

2.2. The role of Maltreatment in Gender Differences in Psychopathy

Males outperform females on almost all characteristics of psychopathy. On the other hand, females score much higher than males when it came to social contextual risk factors for psychopathy, such as emotional and sexual abuse [6]. Children who have experienced abuse may develop the idea that it is "normal" to hurt others [7], ways including emotional abuse, neglect, sexual abuse, physical abuse, or any combination thereof [8]. This leads to a higher rate of violence. Indeed, according to the PCL-R checklist, people with psychopathic traits frequently exhibit violent behavior at an early age. Both the low fear and response regulation models of psychopathy suggest that people with psychopathic traits have deficits in emotion regulation.

According to Asscher's research, emotional regulation is affected by chronic maltreatment, and emotional processing differs between children who have experienced maltreatment and those who have not [9]. Thus, it is possible that maltreatment affects the development of psychopathic traits differently in males and females.

2.2.1. Emotional abuse

Psychopathic traits exhibited in adulthood have a strong relationship with childhood maltreatment [10]. Evidence suggests that girls experience all types of abuse at a higher rate ，including emotional abuse, which is defined as abusive behaviors including humiliation, controlling behavior, financial coercion, isolation, and threatening behavior [11]. Although in Começanha’s study, the rate of experiencing emotional abuse did not vary by gender [12], but there is still an association between emotional abuse and mental health. It has been shown that emotional abuse in childhood, in combination with other factors, can promote the development of psychopathic traits. On Schimmenti’s study in 2015, the correlational analysis revealed the adults who had experienced childhood emotional abuse scored higher on the PCL-R total scores [13]. Borja found in a sample of 193 inmates that psychopathic participants who had emotional abuse presented generally higher level of victimization [14].

2.2.2. Neglection

Compared with other types of maltreatment, the type of neglection has been less studied, but there is still research that supports the fact that it is associated with several behavioral problems. For instance, male victims of neglect are convicted or crimes at four times the rate of adolescents who have not been exposed to child neglect [15]. Skeem also found that the psychopathology embedded in of antisocial lifestyles may be more influenced by environmental risk factors, such as childhood victimization, particularly parental abuse and neglect [16].

2.2.3. Sexual Abuse

1 in 4 women and 1 in 10 men experience sexual violence, physical violence, and/or stalking by an intimate partner during their lifetime. According to the data from National Coalition Against Domestic Violence, 1 in 5 women experienced completed or attempted rape during her lifetime, while 1 in 71 men experienced completed or attempted rape in his lifetime [17].

Based on that, Graham found that childhood sexual abuse showed positive correlations with psychopathic traits such as grandiose and manipulative interpersonal styles, impulsive and irresponsible lifestyle, and antisocial behavior, all of which are included in psychopathic traits [18]. In Schimmenti’s study in 2014, among 139 participants who convicted violent crimes (including 10 participants who showed the highest psychopathic traits), suffered from severe and concurrent experiences of neglect and abuse during childhood [19]. This experiment reveals a clear association between psychopathic behaviors and experiences of sexual abuse.

2.2.4. Physical Abuse

According to the number from National Coalition Against Domestic Violence (NCADV), every third woman and every fourth man have been victims of physical violence during their lifetime. That is about 5.3 million incidents of domestic violence annually among US women aged 18 years and older, and 3.2 million occurring among men. In addition, on average, approximately 6.9 women are physically assaulted by the same partner and approximately 4.4 male victims each year [20]. Campbell found that adolescents with a history of childhood abuse experiences are more likely to score higher in psychopathic traits [21] This claim was again supported by Kolla and colleagues, who showed a predictive association between childhood physical abuse and psychopathy rates among the 25 violent offenders they studied [22].

From the data above, one thing can be seen is that women experience a higher rate of all kinds of maltreatment experiences, while still, males score a generally higher rate in showing psychopathic behaviors. There are two possible explanations for that, one is multifocality, which means that male and female may show different response with maltreatment experiences, the other is that maltreatment is not the only factor contributing to psychopathic rates-there are other environmental factors (e.g. lack of parental warmth, exposure to neighborhood violence) and biological factors (e.g. genetics, hormones).

Although there’s a clear association between maltreatment experiences and juvenile delinquency (which is one of the traits of psychopaths in the PCL-R checklist) in males, but there is no clear association in females. However, child maltreatment is contributed to adult criminal behaviors in both genders, which predicts that the effects on delinquent behavior of child maltreatment may be a bit delayed in girls [23]. This could explain the fact that girls have less juvenile delinquency and are therefore less likely to suffer from mental illness.

Sundermann's study involved 115 female adolescents in an experiment examining the relationship between ER competence and important mental health outcomes in adolescents [24]. The results showed that approximately 10% of the total variance of abuse characteristics was anger, approximately 13% was anxiety, an insignificant number was depression, and about 10% was the total variance of dissociation. One thing that can be seen is that women's primary response to the experience of abuse was anxiety rather than anger or depression. While male CSA (childhood sexual abuse) survivors are more likely to become abuser themselves because the experience was so traumatic for them, especially if they are in denial about the experience [25].

Simon notes that male with maltreatment experiences also tend to have externalizing behaviors (e.g., substance abuse, violence, etc.) [26]. According to the PCL-R checklist, most of these externalizing behaviors are consistent with psychopathic traits, especially the problem of substance abuse. There’s significant association between psychopathy and substance abuse from previous research [27].

Also, other factors should be taken into account when discussing the etiology of psychopathic traits. Biological factors, especially difference in gene, function of amygdala, and hormones between male and female could also be the reason why there’s difference in the rate of psychopathic rate across gender. Overall, the way male and female deal with abusive experiences is different, which may lead to higher rates of psychopathic traits in them.

2.3. Gender Socialization and Psychopathic Traits

It is possible that social expectations can have an impact on the development of psychopathic traits in males and females. There are perceived different expectations on male and female from the society. Both boys and girls are expected to “halve themselves” under the culture’s traditional gender socialization. Girls are permitted to express themselves emotionally and create connections. They are, however, actively inhibited from fully developing and using their public, forceful selves – what is commonly referred to as their “voice”. Boys, on the other hand, are encouraged to develop their public, aggressive identities while being gradually nudged away from full emotional expression and the potential to make and appreciate profound connection [3]. Based on the different traits shows in male and female under the influence of social context, the question was developed that does these social expectations also have different effects on the formation of psychopathic traits in men and women. Gender-role socialization differences may result in psychopathic traits being expressed differently in males and females [28, 29]. There are many studies on gender differences in psychopathy, but little is known about how social expectations play a role in these differences and changes.

3. Method

To have a better understanding about the roles of social expectations and gender on the development of psychopathic traits, a total number of 100 participants will be the inmates that are drawn from the prisons who meet the criteria for psychopathy. At the meantime, there will be another 100 participants who meet the criteria for psychopathy from the society as contrast. In the total number of 200 participants, 50% will be female inmates and 50% will be male inmates. There will be an almost equal number of participants from different age groups because the different generation that the participants come from may have different social expectation towards boys and girls.

To be eligible for the study, the participants’ self-identification in terms of gender, male or female, need to be clear. Because this is an experiment related to one’s perception of the social expectation in terms of gender and the perception of one’s own gender is crucial in this study. In addition to that, the measurement of how other people, for instance, parents, teachers, fellow students and friends treat the participants and reinforce gender norms will be included in the experiment.

During the experiment, we decide to use Qualtrics to create the online survey to cover as much as possible areas in maltreatment, social expectations, that may have affection on the forming of psychopathy in terms of gender. Qualtrics is a software designed for people who have little or no programming knowledge to create surveys and generate their reports in their own convenience. Different version of the survey will also be distributed to the participants several times with a period of time interval due to the reason that this experiment has different age groups. The link of the survey will be sent out to the participants so that part of the participants can completed in proper facility with consistent monitor for security reason.

4. Conclusion

Future study should also focus on the impact of education level on how people are treated in society and then develop a research on whether the receiving of different treatments from the society due to the different education level played a role in the development of psychopath trait in different gender. Besides, the future experiments could also focus on the differences in forming psychopathy in terms of ethnicity as it has been a popular topic among academia.

Human as an intellectual creature has incredible learning skills at an early age to assist them receiving and understanding various emotions. Throughout the interaction with outside world, children learned how to behave and being socialized. Whom has the experience of maltreatment receiving the cues of being abused and scared are not only conditioned with a signal to mimic the violent behavior but will also build a solid wall between themselves and the outside world to protect themselves. They are psychologically isolated.

What more important is, when people seeing psychopath as the evil of the society that deserve to die, the public lacks the awareness that they might also be part of the reason in the development of psychopathic traits. Behind the scene of the psychopath as a case study, it is the inequal treatment of gender behind all this. In the very end of the paper, it is lamentable to see that there are still many cases shows that women and men are treated different with in the environment they grew up.

5. Acknowledgement

These authors contributed equally to this work and should be considered co-first authors.