There is gender bias in our current mental health diagnostic system. This bias occurs for three reasons.
- There are genuine gender differences in the manifestation of behavioral disorders.
- Those creating the diagnostic categories are biased.
- Those making the diagnoses are biased.
Each of these reasons for gender bias is operative with regard to sociopathy. We would hope though that gender differences found in behavioral disorders reflect true physiologic differences between men and women. This week I will attempt to convince you that physiologic differences between men and women account for the higher prevalence of sociopathy in men.
That men and women are different physiologically is apparent from our appearance. Other than the obvious difference in external genitalia, men are on average taller, stronger, have facial hair, deeper voices and smaller breasts. But take each of these secondary sex characteristics individually and you will see where the problem lies. There are some women who are taller than many men. There are other women who are physically very strong and others who have deep voices. Much money is spent on fixing the “problem” of facial hair and small breast size in some women. The point is that gender differences represent group differences in aggregate qualities.
The real question is, “is there some physical difference between men and women that causes more men to develop into sociopaths?” Alternatively, maybe we just label men with aggressive behavior sociopaths and we fail to label women, or we call them something else.
Hormones and sociopathy
There are two fairly consistent hormonal findings in sociopaths as a group. Sociopaths tend to have higher levels of masculine hormones like testosterone (androgens). They also have lower stress hormone (cortisol) output in response to stress. Higher androgen levels have been found in both male and female sociopaths. However, the abnormal stress hormone response to stress has only been documented for male sociopaths. There is one study that shows this characteristic is not present in female sociopaths. Hold this thought in mind because I am going to come back to it.
Borderline personality disorder is more common in women
Although more men than women are diagnosed with sociopathy, there is a sister condition to sociopathy that overwhelmingly more women get diagnosed with. That condition is borderline personality disorder (BPD). There is even more gender bias in the diagnosis of BPD than there is in the diagnosis of antisocial personality disorder (ASPD/sociopathy). It is relatively unusual for men to be diagnosed with borderline personality disorder.
The DSM-IV defines BPD as: “a pervasive pattern of instability of interpersonal relationships, self-image, and affects, and marked impulsivity beginning by early adulthood and present in a variety of contexts.” If you have been involved with a sociopath, you may be saying, “Wow that sounds like my ex!” In fact many with ASPD could also be diagnosed with BPD and vise versa. Nearly 40% of a clinical population met criteria for BOTH disorders in one study.
Many psychoanalysts consider those with ASPD to have an “underlying borderline personality organization.” I can’t really comment on that because it all sounds like psychobabble to me. But I can comment on why there is so much over lap between borderline and antisocial personality disorders, and why one is more common in men and the other in women.
Over the course of human evolution, there has been substantial selection pressure for women to have empathy and self control. Simply speaking, a woman without these had much less chance to survive and reproduce. Empathy is important, but differentially important for males. Therefore, when our nervous systems develop under the influence of our sex steroids, it is relatively more unusual for a woman to develop completely devoid of empathy. Lack of empathy is a central characteristic of ASPD but is not as pronounced in BPD.
The development of ASPD and BPD
Mother Nature also selected for women who are more cautious, less risk taking and more fearful. This is why anxiety disorders are much more common in women. Fearlessness and risk taking are part of the ASPD diagnosis. Anxiety is a central feature of BPD.
On this blog, I have written a great deal about the human social dominance drive. This drive is also called the power motive or need for power. I have explained that this need for power motivates much of the sociopath’s behavior. The power motive is also largely under the influence of testosterone in both men and women. The power motive causes women with BPD to be “manipulative.” But they do not show the proactive aggression that characterizes ASPD. If they did, they would be called ASPD rather than BPD.
So why is there a gender difference in the manifestation of the power motive? The reason is stress hormones. There is an interesting overlap between sex hormones and stress hormones. The interplay between sex hormones and stress hormones is partly responsible for the development of ASPD, and an excessive focus on power in relationships. I believe this is the major reason why we more commonly see BPD in women and ASPD in men.
The hormonal stress response is different in males and females. In boys and men, stress activates the sympathetic nervous system and also releases cortisol from the adrenal gland. The sympathetic nervous system stimulates the testis to release more testosterone. This is likely why childhood stress is related to the development of ASPD in boys and is also why harsh punishment increases, not decreases aggressive behavior in problem boys. Stress substantially increases testosterone in many boys and testosterone increases power motivated behavior.
In social interactions, children learn submissive behavior due partly to cortisol released in response to encounters with adults who are dominant or more powerful. When the average at-risk boy has these power encounters with adults, his body releases more testosterone than cortisol. Thus, power struggles increase dominance/aggressive behavior in at risk boys because these boy’s adrenal glands do not release enough cortisol in response to stress.
Since women do not have testis, they do not have this androgen boost in response to stress. The adrenal glands of some women do release more androgens in response to stress, this is why stress is associated with the development of ASPD in some girls. Remember also, nearly all cultures pressure girls from an early age to suppress their dominance drives, whereas boys are encouraged to be competitive and aggressive.
Most women with BPD were sexually molested as young girls. A history of sexual molestation is also common in incarcerated women and in women diagnosed with ASPD. It is very likely that the body’s response to childhood stress dictates whether a woman develops ASPD as opposed to BPD.
There are many adults with ASPD and BPD who did not experience excessive childhood stress. Many of these adults had ADD/ADHD as children. Impulsivity is a primary symptom of ADHD, BPD and ASPD. In antisocial individuals this impulsivity is associated with the enjoyment of aggression and power over others. In BPD others are manipulated but the aggression is primarily directed at the self.
To sum it all up then, an out of control drive for social dominance is required for the full manifestation of ASPD. Sociopaths thrive on power. Physiologically, boys and men are predisposed to develop an excessive dominance drive. This difference in the power motive is responsible for part of the gender differences found in ASPD and BPD. The other part of the gender gap is explained by increased levels of anxiety in women.