Examining the Relationships Between Autism and Personality Disorders

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"The mind is a labyrinth", to quote the demented psychiatrist villain from the timeless horror film Hellraiser II. And much like any particularly vast and complicated territory, it can often be infuriatingly confusing to traverse it and require many failures before success is achieved and an all-encompassing understanding of its terrain is gleaned. A prolonged detour into an unexplored area may bring nothing but another dead end, and what may seem from a distance to be the long-awaited exit may turn out to be the bitter disappointment of having walked in circles and returned to the entrance.

While great strides have been made in understanding autism, the spectre of the utter lack of medical understanding of autism in decades past still looms large in the form of everything from harmful yet pervasive myths to an epidemic of undiagnosed or misdiagnosed autistic adults. As I have covered in another article, medical understanding of the autism spectrum has evolved tremendously in previous decades. The definition has steadily grown from a clumsy description of a very specific manifestation of what is now considered "low-functioning" autism, to a description of the entire infinite spectrum, from classical "low-functioning" autism to Asperger's and everything in-between and parallel to those.

It is now known that autistic people actually skew quite significantly towards high IQs, yet this fact is utterly anathema to past definitions of the neurotype, and there are still many practicing psychiatrists that are either genuinely unaware of or willfully ignorant in regard to modern developments in autism research. Many autistic adults, such as myself, escaped diagnosis as children in spite of being forced to see a psychiatrist, for this reason, and many others were misdiagnosed with something else that happens to share some of autism's traits. Women and girls are still four times less likely to receive an autism diagnosis than men and boys, and I will explore a possible partial explanation for why later in this article.

Although autistic children are very commonly misdiagnosed as ADHD or sometimes not given any diagnosis at all, it is also surprisingly common for their behaviours to be interpreted as signs of a personality disorder. In comparison with autism, which is a neurotype defined by notable physical differences across the entire brain, personality disorders are defined by specific patterns of thought and behaviour that are considered markedly abnormal by society, and/or interfere with a person's ability to function.

While it is believed that personality disorders occur in around 9% to 10% of the general population, it is still uncertain just how prevalent they are in autistic people. A 2012 study on the subject that looked at a group of 54 autistic adults - 52% female, 48% male - on the Asperger's ("high-functioning") side of the spectrum, showed that 48% met the criteria for at least one personality disorder and 9.3% met the criteria for two or more. Much more shockingly, a 2009 study on 117 autistic adults - this time 33% female, 67% male, and only 55% aspie - revealed that 62% had at least one personality disorder, 35% had at least two, and 17% had at least three.

Moreover, the 2009 study counted the autistics that were diagnosed with Asperger's separately and in that sub-group, a whopping 68% showed signs of at least one personality disorder, 40% showed signs of at least two, and 18% showed signs of at least three, noticeably more troubling statistics than the ones that were revealed for the lower-functioning groups in the study. This is likely reflective of the increased struggles that autistic people labeled "high-functioning" face due to being unable to secure the support and accommodations they need to function because their ability to mask,, coupled with their higher intellect makes it appear that they are not struggling.

Personality disorders are grouped into three clusters based on similiar patterns of thinking and behaviour: Cluster A (Paranoid, Schizoid, Schizotypal), Cluster B (Antisocial, Borderline, Histrionic, Narcissistic), and Cluster C (Avoidant, Dependent, Obsessive-Compulsive). I have split the article by these clusters for organisation's sake. I will also largely be referring to personality disorders by their acronyms, despite my usual disdain for abbreviations and acronyms, for easier readability, as the names of personality disorders are not typically capitalised.

Nothing written here is meant to imply that autism is a mental disorder or a disability, as research has made an exceedingly strong case for it being a neurotype with a myriad of benefits to balance out its apparent disadvantages. The fact that autistic people are so prone to having personality disorders and mental health conditions is a reflection of the truly abysmal way society at large treats autistics from the cradle to the early grave. The fact that a square peg will be broken if it is brutally forced into a round hole does not in any way imply that the square peg is inferior to or deficient compared to a circular peg.

This article was a mess to write, owing to my chaotic and disorganised way of working. I originally wanted to cast a wide net and cover every single major mental condition that autism can be co-morbid with or that may be misdiagnosed as, but I quickly realised that it was a mistake to attempt to cover that much information in one article. I wound up cutting some things I wrote out, and I will probably eventually write a follow-up article covering the relationships between autism and various other neurotypes and mental conditions such as ADHD, schizophrenia, PTSD, and many more. Stay tuned!

Please note that many of the studies I linked to for reference are, lamentably, locked behind paywalls. If you are interested in reading any of them, you can bypass this paywall using the wonderful free website known as Sci-Hub. Just copy and paste the URL for the study into Sci-Hub and click "Open". The link to the website may change as some point, but you should be able to track it down by typing "Sci-Hub" into your search engine of choice.

Cluster A Personality Disorders: Odd/Eccentric

The umbrella of cluster A personality disorders includes paranoid personality disorder, schizoid personality disorder, and schizotypal personality disorder, and is characterised by behaviours, beliefs, and patterns of thinking that come off as off-putting, illogical, and bizarre to other people. Although the personality disorders in this cluster, notably schizotypal and paranoid, may appear similiar to schizophrenia, they are entirely distinct and none of them involve the hallucinations or complete disconnection from reality that characterise schizophrenia.

Schizoid and Schizotypal

The similiarly-named schizoid (SPD) and schizotypal (STPD) disorders have a number of similiarities but also some key differences. Both disorders involve a very strong desire for solitude and a lack of interest in friendships and other relationships along with social interaction in general, as well as a rich inner fantasy world and unconventional mannerisms and speech. However, while schizoid's mannerism oddities usually manifest as overt stoicism, limited to no emotional expression, and overly formal or monotone speech, people with schizotypal can have all sorts of eccentric mannerisms and tend to dress and "carry themselves" in unconventional ways.

The oddness extends to a person with STPD's entire way of thinking, as they often have magical thinking, believing in things that make no logical sense such as the idea that they have supernatural powers or that some mundane thing actually has a secret personal meaning for them. Additionally, while people with SPD usually genuinely do not care about what anyone else may think about them and will react even to criticism and praise with complete apathy, schizotypal often carries with it persistent social anxiety, although stemming from paranoia and distrust of other people as opposed to perceived shortcomings in oneself.

From a surface point of view, the two personality disorders do seem to be oddly similiar to autism, and indeed, both aforementioned studies on the prevalence of personality disorders in autistic adults showed that they are apparently quite prevalent among autistics: 21% of the subjects in the 2009 study and 26% of the subjects in the 2012 study met the criteria for schizoid, while 15% in the 2009 study and 2% in the 2012 study met the criteria for schizotypal. This is up from a prevalence of anywhere between 3% to 5% for SPD and 3% for STPD in the general population.

A perhaps clearer picture is painted however, when looking at a 2019 study on the overlap between autism and SPD. This study found that 54% of "high-functioning" autistic males showed strong signs of SPD, most notable being an absence of close friends and a preference for solitary activities, yet only 5.8% actually met the full diagnostic criteria. Significant schizoid diagnostic criteria such as a lack of desire for or enjoyment of close relationships, lack of strong emotions, and indifference to praise and criticism were only present in a small number of the subjects.

Ultimately, while there does appear to be some genuine correlation between autism and SPD, most autistic people only coincidentally display some signs of schizoid, all of which can be easily explained via other factors. For example, autistic people can display the same utter stoicism to the outside world that is characteristic of SPD either because they are too overwhelmed to show any visible reaction, or because prolonged masking has made them able to maintain a poker face even in emotionally intense situations. Autistic people may also not know how to appropriately express emotion, especially in delicate situations, and may simply display a stoic facade instead, much like someone staying silent in the midst of a heated and emotional political or religious argument that they do not want to risk getting involved in.

The stigma behind autism and autistic behaviours, and the fact that neurotypicals are prone to rejecting and ostracising autistic people, regardless of where they may be on the spectrum, based off of initial judgments made during in-person interactions, can make developing friendships or other relationships difficult if not impossible.

Additionally, since autistic children do not naturally absorb and adopt social norms from other people in order to conform, they are left struggling in teenhood and adulthood to understand the often arbitrary and complicated rules for what is acceptable and expected in relationships. I've quipped before about my own pathological fear of and distaste for receiving gifts or other favours, which largely stems from not wanting to owe anyone because I do not understand proper reciprocity and do not want to have to rack my brain about it.

To an autistic person, the neurotypical social world can feel like a club full of people who all speak a shared foreign language and have a cornucopia of shared jokes, customs, and norms that they are unwilling to explain to outsiders but that they expect everyone to demonstrate a proficient and intuitive understanding of, and will get offended if someone shows any signs to the contrary. I would expect most people to develop symptoms of SPD if this was the only outlet for social interaction that they had available to them.

Extended isolation also makes many people more aware of both the benefits of it and the annoyances of having other people around. Jim Carrey has a famous quotation on the subject that I personally always found incredibly relatable: "Solitude is dangerous. It’s very addictive. It becomes a habit after you realise how peaceful and calm it is. It’s like you don’t want to deal with people anymore because they drain your energy." As a personal anecdote, having made it through many ruts of severe depression with only my own company to comfort me, I also feel that these kinds of experiences can make a person extremely emotionally self-sufficient, causing formation of schizoid-esque behaviours.

It is also worth noting that autistics and neurotypicals generally derive pleasure from substantially different activities and have radically different sensory tolerances and cravings. Speaking very generally, autistics are more interested in ideas and things, while neurotypicals are interested in people. It is completely understandable that most neurotypicals, especially extroverts, would not be even remotely allured by the prospect of spending a Saturday night sitting in a quiet room with an autistic person and infodumping back and forth about special interests, but most autistic people are at least as equally turned off by activities that neurotypicals find enticing, such as eating in public, social events, and so forth.

As I have said elsewhere, I liken the social attitudes of many autistics, such as myself, to those of typical cats. It's not that we hate socialising or hate other people, but that we treat it the way a connoisseur treats art: we can derive pleasure from socialisation, but we won't go seeking it out purely for its own sake and are fine with abstaining if there is no good company to be found, or if we simply deem that it is too much effort to obtain and maintain it. Cats are often presented as being utterly uncaring and aloof, but as anyone who has actually had the blessing of having a cat in their life knows, they can be incredibly social and affectionate with someone who has earned their trust and adoration.

The DSM-5 (Diagnostic and Statistical Manual of Mental Disorders) makes a very interesting related point by noting that immigrants from foreign countries/cultures, or even people migrating from rural to urban areas or vice-versa, may appear to display symptoms of SPD such as coldness and a preference for solitude, as defensive behaviours against unfamiliarity with the local language/social norms/customs, and/or due to perceived exclusion. Additionally, people from sufficiently different cultures may even be typed as having STPD due to the apparent oddities of their behaviours, beliefs, and rituals.

Given that autistic people's differences are great enough to warrant a widespread sentiment of feeling like an alien from a different planet (I have even read anecdotes from autistic people who wound up fitting in and functioning better as immigrants in a foreign country than as natives in their own country, due to it being expected and understood by the people there that they would have different mannerisms and ways of communicating due to their foreigner status!), this could be a vital clue to the apparent mass co-morbidity of autism and SPD.

Incidentally, prior to discovering I was autistic, I had wondered at times if my struggles to connect to other people might've been due to me being a Russian immigrant, since some of my differences, such as never smiling without a good reason, are considered perfectly normal in my homeland.

Given how many autistic adults have escaped diagnosis as children due to a lack of medical understanding of autism at the time, it's highly likely that many were instead diagnosed with SPD due to the coping mechanisms they had to adopt. I've read a number of anecdotes from psychiatrists who have worked with adults that have been diagnosed with SPD that genuinely want close relationships but have a storied history of having their boundaries violated and ignored in their childhood and are afraid that every relationship they have will work that way, which further strengthens this theory.

For many autistic people who were never diagnosed as children, it is very possible to have lived through a very unintentionally abusive childhood, even at the hands of well-meaning parents who would never purposefully harm their progeny. Something as innocuous as suddenly disrupting routine by taking a child on an unannounced vacation or cleaning/rearranging their room for them can be quite literally traumatic if the child is autistic, as an example. There is no logical reason that a neurotypical whose child never received an autism diagnosis would believe that their child is actually having a terrified meltdown over a trip to the beach, as opposed to throwing a temper tantrum.

Either way, I must say that I am still very hesitant about labeling people as "disordered" or "ill" because of the way their brain works (I do use "personality disorder" here, but in most cases only because if I started making up my own words, no one would know what I am talking about!), and I am especially hesitant about attaching that label to schizoid. One could argue that it is a very useful defence mechanism, and in an age where people commit suicide over not being able to have face-to-face interactions for a few months due to a lockdown, I daresay that it is significantly healthier than the norm. Being (excessively) reliant on the company and validation of other people brings an entire host of problems, such as susceptibility to abusive relationship partners, cults, or other exploitative bad actors, that make having SPD look quite preferable. More on this later in the dependent personality disorder section.

Regarding schizotypal disorder, it is worth considering that, in addition to the STPD-shared social oddities (e.g., monotone or awkward tone of voice, lack of eye contact, inability to share a conversation equally with another person, etc) caused by our hyper-connected brains, autistic people are inherently wired to be nonconformists, and as such will often dress and carry themselves in ways that are considered unusual based on social norms. My unapologetic embracement of the colour pink and other girly aesthetics is an immediate example of this.

Without the context of our autism being known, this can be interpreted as signs of STPD. Furthermore, prolonged isolation means a person has no anchor to pull them back to reality when their mind starts going down bizarre tangents, which can cause much of the magical thinking that STPD is known for, something I have observed in myself many a time in the past.

Paranoid

Paranoid Personality Disorder (PPD) involves a persistent preoccupation with suspicions of being harmed, exploited, or otherwise wronged by other people, regardless of whether any evidence exists to back these suspicions up. This obsession leads a person to read into meanings that may not exist and summarily become enraged and develop prolonged grudges against people who have not done anything to slight them. The DSM lists interpreting compliments as sarcastic insults, or interpreting honest mistakes from other people as purposeful attacks, as examples of these tendencies. This can lead to a person with PPD perpetually having an argumentive and hostile deameanour, or a cold and aloof one.

People with PPD struggle to form relationships because they are afraid to become vulnerable or confide any information in others, believing that it will be used against them later. Should they develop a relationship, they may be haunted by beliefs that their lover or spouse is unfaithful to them, which can drive them to be extremely controlling of their partner. They may respond negatively even to genuine loyalty and kindness from people close to them because they are unable to bring themselves to believe it to be real.

PPD is estimated to occur in the general population in anywhere from 2.4% to 4.4% of people, and was observed in 19% of participants of participants in the 2009 on autism and personality disorders, including 19% of the participants on the Asperger's part of the spectrum. The 2012 study did not detect it in a single person, but did note that people with PPD are far less likely to accept an invitation to participate in a clinical study, and that the study could thus be suffering from this unavoidable bias.

Lamentably, paranoid personality disorder's relationship with has not been looked at anywhere near as extensively as that of some other personality disorders. The only other relevant information I was able to track down was a a 2016 paper detailing an analysis of data from research papers obtained from trawling four academic databases for any studies that evaluated the correlation between autism and paranoia in general. The seven total studies that were used, a body of data involving results from 180 total autistics (28 female and 152 male), the majority of whom were diagnosed with Asperger's, universally showed that autistic people are more likely to have paranoid ideations compared to neurotypicals.

There is no scientific consensus as to what causes paranoid personality disorder, but the most popular theories are that it stems from hostile childhood experiences involving abuse from often erratic caregivers. Going by this view, children who were subjected to unpredictable and unavoidable abuse were then forced to develop a paranoid mindset in order to help them predict and cope with their predicament, which eroded their ability to trust.

The aforementioned paper on autism and paranoia proposes a fairly similiar explanation. According to the authors, autistic people are more likely to have a paranoid mindset due to being far more likely to be taken advantage of and bullied in their childhood, both by peers and authority figures. It could also be a way to compensate both for the increased naivete that is so common in autism, and the difficulties with reading and understanding neurotypicals' intentions.

As in the case of schizoid, it is possible for parents who simply do not know any better to hurt an autistic child enough for them to develop this disorder. Speaking from my own experience, I would also add that it may be partly because some of us are so naturally talented at noticing patterns that we may start finding them where none exist.

Another thing that needs to be taken into account is that, as explained in my article on the Intense World theory of autism, the autistic brain is hyper-connected, and this hyper-connectivity is most pronounced in the amygdala, which controls fear, anxiety, and the fight-or-flight mechanism, among other things. As a result, autistic people (especially children) have a greatly increased likelihood of developing fear memories in response to unpleasant stimuli, and a much less likelihood of the memories fading away with time via fear extinction. Even without anything else, these mechanisms likely make autistic people more prone to develop paranoid ideas.

Cluster B Personality Disorders: Dramatic/Emotional

Cluster B personality disorders include antisocial personality disorder, borderline personality disorder, histrionic personality disorder, and narcissistic personality disorder. This cluster is marked by elevated emotionality and issues with regulating emotions, dramatic and unpredictable behaviour, and major difficulties interacting with other people.

I will not be covering histrionic (HPD), a disorder marked by theatrical and dramatic attention-seeking behaviour and a ceaseless obsession with attention and approval, as I have never seen a single piece of medical literature nor anecdote mentioning even one autistic person having it or being suspected of having it, and quite frankly find the prospect of that occurring very often to be hard to believe. Neither study that I referenced for this article was able to detect HPD in a single subject, and every reference to relationships between autism and this disorder that I have seen in medical literature agreed that this co-morbidity is incredibly unlikely.

Antisocial and Narcissistic

Antisocial personality disorder (ASPD) and narcissistic personality disorder (NPD) are closely related and are both characterised by a delusional, inflated sense of importance and entitlement, coupled with a complete lack of regard for anyone else. The main difference is that narcissism is typically not categorised by overt aggression, criminal behaviour, and impulsivity the way ASPD is. Additionally, NPD typically involves a constant thirst for attention and admiration, something ASPD usually lacks.

The extreme impulsivity and willingness to engage in dangerous and criminal behaviour in ASPD is likely due to the fact that people with ASPD lack much of the brain connectivity that allow humans to feel fear and learn from their mistakes. This is in contrast to narcissists, who do feel fear and are even capable of developing social anxiety, in spite of how counterintuitive that may sound. Interestingly, it can be thought that, in a sense, the brain activity associated with ASPD is the exact opposite of what manifests in autism, where the brain excessively creates fear memories and refuses to let go of them as time goes on.

While I have not heard of any cases of an actual psychiatrist misdiagnosing autism as narcissistic or antisocial, and am quite doubtful that such a thing has ever occurred, it is indeed possible for autistic people to have these disorders. Although the 2012 study did not find either disorder in the participants, the 2009 study found that 3% met the criteria for ASPD and another 3% met the criteria for NPD. Among the aspie sub-group, 2% had NPD and none had ASPD. For comparison, ASPD is estimated to exist in 1% to 3% of the general population and NPD anywhere from 1% to 6%.

Beyond these statistics, I have heard numerous anecdotes about romantic partners and friends of an undiagnosed autistic person doing an armchair diagnosis of narcissism to explain their behaviour. The most immediately obvious reasons are likely because autistic adults tend towards being very aloof and may avoid eye contact and social sprinkles such as greeting people when walking into a room, engaging in smalltalk, or making eye contact, all things that more insecure extroverts may interpret as snobbiness and arrogance. I have slowly come to vaguely understand the importance of such things, but as an ultra-introvert I still cannot help but find people's strong expectations for them to be overly needy.

Due to a lack of understanding of reciprocity or conversational rules, autistic people can also give off the impression of being self-absorbed due to either completely dominating a conversation or alternatively, barely speaking or simply ignoring people trying to make conversation altogether. This impression is only further reinforced by the fact that many of us can be off-puttingly blunt and do not hesitate to correct people in public if they say something that is factually incorrect, a behaviour that many neurotypicals are offended by, for reasons that are beyond me.

One specific grievance that I have heard repeated numerous times is from romantic partners of an autistic person who become upset over their partner never expressing any affection for them. While neurotypicals typically want constant reassurance from their partner that they still love them, an autistic person may simply tell their partner that they love them a single time with no further expressions of affection, and then assume that their partner will understand that this hasn't changed since they never said anything to the contrary afterwards.

I have also seen a number of anecdotes that involved a woman who was frustrated with her husband's lack of affection, self-absorption, and apparent lack of empathy and had come to believe that he was a narcissist, before discovering that he was an undiagnosed autistic and that she was misunderstanding his communication just as badly as he was hers.

Yet another reason that autistic people may appear to come off as narcissists or sociopaths lies in the fact that many of us, especially those who were never diagnosed as autistic in our childhood, are used to people not empathising with us and violating our boundaries due to being unaware or indifferent to our many issues. Not being shown any empathy for one's daily struggles and being chastised for supposedly lacking empathy towards others because of mysterious things that one never knew they were supposed to do or not do, can inevitably turn anyone into a callous scoundrel after a while.

In my personal case, although I have grown beyond this, I had a long streak of reveling in treating people like garbage for no reason in my younger years because I came to view everyone I met as a potential enemy unless and until they proved otherwise. I am not proud of my past behaviours, and have no intention of attempting to justify them, and merely bring this up as an anecdote.

While autism and NPD/ASPD are popularly associated with a lack of empathy, this is partially untrue for all three of them. There are two forms of empathy - cognitive empathy, which involves being able to read other people's emotions and see the world from their perspective, and emotional empathy, which involves actually being able to feel other people's emotions and empathise with them. These days, it is believed that NPD/ASPD are associated with enhanced cognitive empathy and an utter lack of emotional empathy, while autism involves a lack of cognitive empathy and an overload of emotional empathy.

It's worth mentioning that the idea of autistic people lacking cognitive empathy is something that is being increasingly disputed. The double empathy problem posits that the myriad of ways that autistics can unintentionally offend neurotypicals (and vice versa) can be attributed to the fact that autistics and neurotypicals naturally communicate in different ways, and autistics are viewed as having communication "deficits" merely because neurotypicals comprise the vast majority of humanity, and most of them consider their way to be the only correct one and do not want to make the effort to see things from the autistic person's perspective.

Ultimately, the key difference between autism and narcissism is that autistics may come off as rude and uncaring because they are unaware of what is expected of them, while narcissists know and simply do not consider anyone other than themselves to be worthy of kindness or respect unless they are someone that the narcissist wants something from. Unlike most autistic people, narcissists also tend to have excellent social skills.

Borderline

Borderline (BPD) is a personality disorder that is characterised by hyper-emotionality and hyper-sensitivity, coupled with an extreme fear of abandonment and rejection. People with borderline often struggle severely with relationships and social interactions because their obsession with avoiding rejection leads them to read into signs that may not be there, similiar to PPD. These tendencies make a person prone to constant mood swings, an unstable and ever-changing self-image, and impulsive behaviour such as melting down on people or suddenly ending relationships for no apparent reason as a sort of preemptive strike against what they mistakenly perceive as impending abandonment, in a sort of relationship equivalent of "you can't fire me! I quit!"

In extreme cases, people with BPD can engage in dangerous behaviour such as self-harm and even suicide, or have full-blown psychotic episodes. Even in milder cases, the lack of emotional permanence can cause a person with BPD to suddenly quit a job or permanently end a close relationship over a perceived slight that caused them to instantly lose all attachment.

Borderline is estimated to affect 1.6% of the general population, and was observed in 9% of autistic people, and 7% of those diagnosed with Asperger's in the 2009 study on autism and personality disorders. The 2012 study did not observe BPD in any of the subjects. Additionally, a 2007 study on 41 patients with BPD found that 42% of them showed traits of autism while 15% were diagnosed as autistic.

Although autism and borderline are undeniably two distinct and completely different things, an unexpectedly significant amount of overlap does exist between them. A fascinating 2017 study that looked into the issue of autistic people being misdiagnosed with borderline had groups of autistics, non-autistics diagnosed with BPD, autistics that were also diagnosed with BPD, and non-autistics that were not diagnosed with BPD, complete surveys testing their ability to empathise and to systemise, as well as the famous Adult Autism-Spectrum Quotient test.

Systemising is the process of detecting and analysing logical patterns in the world and using them to build mental systems to understand it. The reason for the tests was due to a popular theory devised by famous autism psychologist Simon Baron-Cohen, which states that autistic people are unusually talented at systemising to the detriment of being able to understand chaotic and unpredictable systems such as those governing the social world.

The results of the study were quite telling. Although the two non-autistic groups strongly outscored the autistic groups in the survey testing for cognitive empathy, the non-autistics with borderline received virtually the exact same average score on the systemising test as the autistic group did, far outstripping the neurotypical groups. Additionally, the "non-autistics with BPD" had an average AQ score approximately in between that of the autistic group and the non-autistic, non-BPD group. Furthermore, the "autistics with BPD" group had by far the highest AQ score of them all.

On the note of Simon Baron-Cohen, he co-authored a paper in 2015 with fellow autism researcher Meng-Chuan Lai on the subject of autistic adults who escaped diagnosis as children due to the medical understanding about the autistic spectrum being limited to classical autism at the time. In this paper, they noted that autistic women and girls in particular are susceptible to being misdiagnosed with borderline due to the overlap between the two phenomenon.

Autism is still severely under-diagnosed in women and girls, and many women go through a myriad of false diagnoses before finally being properly identified as autistic. This is believed to be as a result of autistic women being better at masking as neurotypical. The DSM-5 notes that girls that do get diagnosed as autistic are significantly more likely to have noticeable intellectual impairments than autistic boys, which supports this notion.

Lai and Baron-Cohen have also suggested that, due to the bias stemming from autism being considered a male-centric disorder, the more people-centric special interests and obsessions exhibited by autistic girls may fly under the diagnostic radar. An autistic boy's obsession with fossils may be recognised as a sign of autism, while an autistic girl's obsession with other cultures might be viewed as typical, as an example.

While a girl's autism may initially go unrecognised and she may have no troubles functioning initially, it will likely lead to significant difficulties in interpersonal situations and executive function in teenhood and beyond, leading the girl to seek psychiatric help. Due to the stigmas of autism being an intellectual disability, male-centric, or something that only occurs in children, it is far more likely that a doctor will blame the female patient's issues on a personality disorder, with borderline, which causes severe problems in relationships along with executive dysfunction, being one of the more convincing culprits.

Much of the reason people with BPD are prone to being so unstable is because they see the world through a "black-and-white" lense, a phenomenon known as polarised thinking, or black-and-white thinking. The latter term is used to mean that people with this sort of mindstate are unable to see any "shades of grey", and only see things as being all good or all bad. As an example, someone may only be willing to believe that they, or someone they know, is a wonderful person or a worthless piece of garbage, and will immediately shift to the other option as soon as the first one no longer seems entirely believable.

This is believed to be caused in BPD by heightened emotional responses developed in response to childhood trauma, and is also a common trait (although not nearly as intensely as in BPD) in autistic people, especially in children, but also in adults when they are in a state of emotional or mental overwhelm. It doesn't help that childhood trauma is significantly more likely in autistic children, especially girls. Autistic children are three times more likely to experience sexual abuse than neurotypical children, and girls make up over 90% of those cases.

As a personal example of autistic polarised thinking, I have consistently struggled greatly with rating creepypastas on the Haunted House section of this website and still spend time questioning a number of the ratings I gave, because it's naturally difficult for me to judge them in more nuanced ways than "I LOVED IT! 5/5!" or "I didn't like it; definite 1/5 crap". This is also secretly half of the reason that the Feelspastas are in their own category, as I would not be able to resist handing out 5 stars to every single one of them purely due to the fact that they made me cry. It's almost akin to a mother thinking that everything her child creates is a masterpiece, except the criteria system is applied to everything.

Another consequence of polarised thinking in autistic people is the development of a very strong sense of justice that makes it impossible to let go of things. While autistic people aren't likely to end long-term friendships or relationships because the other person took too long to respond to a text message the way someone with BPD might, we can suddenly and permanently cut people off because of a disagreement regarding one of our values that made it impossible for us to hold any respect for them any longer. I have done this many times and have had a former long-time autistic friend do it to me as well. As much as I detest George W. Bush, something about his quote - "Either you are with us, or you are with the terrorists" - always felt very kindred to my thought processes.

The DSM-5 notes that fears of abandonment and the subsequent outbursts in BPD can occur as a result of changes in plans or environments that imply abandonment, such as a friend changing plans or being late to a meet-up. The need for predictability and routine can trigger severe (and by definition, involuntary) meltdowns in autistic people, especially children, when such events occur, due to sheer stress; another way that autism and BPD can superficially mimic each other. Similiarly, depending on an autistic's emotionality and sensory issues, phenomenon such as being screamed at or hearing a door or a drawer slam loudly can trigger a full-on depressive episode or a sudden fit of explosive rage, something that could be attributed to BPD if a person's autism is unknown.

Self-harm, which is common in BPD, also can occur in more intellectually deficient autistic people, primarily in the form of injurious forms of stimming such as banging one's head on a wall or hitting oneself. Usually however, stimming is limited to benign actions such as pacing, rocking, and finger flicking. Suicidality is also very unusually high for both autistics and people with BPD - the suicide rate among autistics is 10 times that of the general population, and the suicide rate among people with BPD is 50 times that of the general population, with 75% of people with BPD attempting suicide at least once, and anywhere from 3% to 10% succeeding. One study showed that autistic people with BPD are even more prone to suicide.

Although borderline mostly does not involve the hyper-connectivity and subsequent hyper-activity that defines autism, a 2013 study did find that it is linked to a smaller and hyper-active amygdala, which causes a person to be unable to properly react to threatening situations and results in "thoughtless" and hostile responses to stressful stimuli. Indeed, while people with BPD are known for extreme outbursts of rage towards lovers or friends in response to perceived abandonment, these are often summarily followed by periods of remorse once the person returns to their senses, accompanied by bouts of self-hatred due to the belief of being worthless and/or evil due to the outburst.

Essentially, it can be postulated that while autism and borderline are both marked by hyper-emotionality and issues with emotional regulation, people with borderline are significantly less able to control these issues than most autistic people are, and typically do not rely on things such as stimming or withdrawing from people to cope with the constant overwhelm they receive from the world. While there does exist a more subdued variant of BPD called quiet BPD or "high-functioning" BPD, where a person is able to mask their mood swings, it still involves the same constant rollercoaster of depression, anxiety, and suicidal ideations that the regular form of BPD does.

Cluster C Personality Disorders: Anxious/Neurotic

Cluster C is characterised by crippling fears and anxieties targeted at specific things and includes avoidant personality disorder, dependent personality disorder, and obsessive-compulsive personality disorder.

Avoidant

Similiar to BPD, avoidant personality disorder (AVPD) is marked by extremely elevated sensitivity to other people's reactions and a paralysing fear of rejection, resulting in a distorted sense of self and an extremely timid demeanour. Unlike the case of BPD however, where a person constantly oscillates between jubilation and despair, people with AVPD consistently have little to no self-esteem and experience severe anxiety and fear of people and social situations regardless of whether there is any implication that they are being or will be rejected or mistreated. As the name of the disorder implies, people with avoidant tend to isolate themselves and avoid people whenever possible due to the monumental weight of their anxieties.

Although similiar in definition to social anxiety, AVPD's symptoms are markedly more severe and crippling, sometimes going as far as to make a person too dysfunctional to hold down a job or even attend an interview for one. Moreover, while people with social anxiety are often aware that their shyness is the result of pathological thinking, people with avoidant usually internalise their feelings of inadequacy, and as such, believe them just the same as people with other personality disorders consider their behaviours and beliefs to be perfectly sane and logical.

These ingrained beliefs cause people with AVPD to fiercely dread rejection and criticism of any sort, as it is the equivalent of rubbing salt into a gaping wound. Due to their hyper-vigilance, people with AVPD may also have an unusually strong ability to detect even very subtle cues of disapproval and rejection. Additionally, a person who has social anxiety may function without issue when around family, close friends, or while alone, while the self-loathing inherent in AVPD will continue to haunt a person no matter where they are or who they're with.

While AVPD is estimated to occur in anywhere from 1.5% to 2.5% of the general population, it was detected in 25% of participants (29% in the Asperger's group) in the 2009 autism/PD study and 13% of the ones in the 2012 study. While AVPD does not overlap with autism in symptomology, these statistics are not at all surprising given how much autistic people struggle in the neurotypical social world, how overwhelming and frightening sensory stimuli can be, and how much the hyper-connected autistic amygdala predisposes a person to develop and never shed strong fears of things. Studies have confirmed that anxiety, phobias, and even PTSD are far more common in autistic people than in neurotypicals.

As mentioned earlier, autistic people do not intuitively adopt social norms, and usually only pick on them after they are reprimanded for breaking rules that they previously did not know about. While some of this criticism can be gentle, it so often comes in the form of harsh condemnation or bullying, that an autistic person becomes hyper-sensitive to criticism as a whole to the point that even the hypothetical thought of it can become crippling because of the pain associated with it. A fitting metaphor may perhaps be that neurotypicals learn social rules by burning their hand on an oven once, while autistics learn by having someone grab them and burn their hand on an oven any time they enter the kitchen until they learn to avoid the room altogether.

Furthermore, in a chain of events reminiscent of a snake eating its own tail and choking on its feces, every single admonishment an autistic person receives for their social missteps can form a permanent automatic self-checking mechanism that runs in their head every time they have to interact with someone. As time goes on and these stack up, it can lead to an insurmountable mental overload any time an autistic has to interact with someone as their brain is too flooded with a cacophony of voices screaming anything from "MAKE EYE CONTACT!!! BUT NOT FOR TOO LONG OR FOR TOO LITTLE!!!" to "MAINTAIN THIS SPECIFIC POSTURE AND FACIAL EXPRESSION!!!" to even focus on the conversation at hand. The added strain of having to maintain eye contact, which is usually very stressful for autistic people, can serve as the elephant that breaks the camel's back.

Incidentally, I truly believe this is at least a large part of the reason that many autistic people have issues regulating their tone of voice when interacting with other people, as I noticed a while ago that I only have this problem when speaking with other people and sound perfectly "normal" when talking to myself while driving as a way of brainstorming or ruminating. I have also noticed it goes away when I'm in a good state of mind and becomes markedly worse during bouts of sleep deprivation. I suppose this is another reason that autistic people tend to strongly prefer the companionship of cats and other animals to that of humans.

As I explained in my Intense World article, it is not that autistic people are "slower" at processing things than neurotypicals, so much that our brains take in and have to process so much more information (42% more, on average) than neurotypical brains. Many autistics, such as myself, have an almost supernatural ability to read subtle cues in people, and struggle to communicate "properly" as a result of the information overload. On a bad day it can feel like motion sickness without the physical symptoms. This ability also causes us to pick up on very minute signs of disapproval that a person themselves is likely unaware that they are expressing, which also happens to be a sign of AVPD.

This information overload can also lead to chronic avoidance of crowded areas and social events because of how overwhelming and sometimes even frightening all of the noise and other sensory stimuli can feel. The flood of stimuli that the neurotypical brain can either comfortably filter out or even avoid processing can make the autistic brain feel like they have dozen people in their face all competing for their attention by screaming frantic and incoherent gibberish at them at the same moment, as they struggle to make out the voice of their conversational partner in all of the commotion.

In summary, the previously mentioned tendencies of the autistic brain to create fear memories more easily, as well as to not naturally extinguish them, coupled with persistent sensory and social difficulties, can serve to make autism the perfect incubator for AVPD. Every negative experience essentially becomes a brick in an increasingly suffocating social tomb.

Dependent

Dependent personality disorder (DPD) is defined by an inability to function alone and take care of oneself, coupled with a crippling fear of being abandoned by whomever the person views as their caretaker. This manifests in a person in a myriad of ways such as a crippling fear of being alone or outright inability to be alone, an inability to take care of oneself or make even simple decisions without significant reassurance and assistance, submissive and excessively conflict-avoidant behaviour in the interests of retaining the approval of their caretaker, and elevated sensitivity to rejection or criticism.

People with DPD believe themselves to be unable to function without another person's support and will cling to a lover, spouse, parent, or other caretaker for dear life, often winding up in abusive relationships because they would rather put up with severe mistreatment than risk being left alone. The inability to be alone lamentably often draws people with DPD to narcissists or sociopaths because of how desperate they become for a relationship if they happen to lose the one they're in. There also exists a lack of self-esteem and a pervasive "learned helplessness" where a person will rely on someone else to take care of life tasks for them because they believe themselves to be mentally incapable of doing so, which further fuels their clingy behaviour.

Dependent is believed to have a prevalence of 0.5% in the general population, and was observed in 5% of the participants (3% among the aspies) in the 2009 study, and none of the ones in the 2012 study. It needs to be noted that, regarding the apparent significant difference in prevalence between autistics and neurotypicals, the DSM-5 notes that DPD is very frequently co-morbid with the previously discussed AVPD, which is quite common in autistic people, due to the tendency of people with that condition to very closely attach themselves to whomever they trust enough to have a close relationship with.

The DSM does specifically differentiate between DPD and dependent behaviour that is the result of a medical condition or disability, which one could argue is the case in many such situations, however. There are also, of course, numerous cases of high support needs ("low-functioning") autistic people that are unable to live independently at all and require a caretaker.

Purely speculating here as I have neither data nor an anecdote to back this assertion up, I believe it's possible that autistic people are more likely to display signs of DPD as a result of learned helplessness stemming from internalising the widespread stigma of autism. While I personally escaped diagnosis as a child, I have read numerous painful anecdotes, from anything from people labeling autistic children tragedies, to "autism parents" grieving the existence of their child, blatantly within earshot of the child themselves. The fact that autistic children are far more likely to be reprimanded due to all of the things they do not intuitively learn to do or not do, coupled with the increased sensitivity to criticism that is common in autism (especially for autistics who have AVPD, BPD, and/or PPD) can also add much fuel to this fire.

Eventually this can culminate in an autistic person feeling that they are too inept to ever have any success with life tasks, and summarily clinging to their parent(s) or other caretaker at any cost, believing it is the only way they can survive. Although I myself do not have DPD and did not even know I was autistic until about a few years ago, I have often refrained from even attempting to tackle milestones such as learning how to drive a car because I was automatically convinced that I could never learn to do so, and my father had to push for quite a while in order for me to make any effort to try. Quite ironic since I now regularly drive like a lunatic out of a desire for efficiency.

Superficial overlap between autism and DPD may also occur, stemming from autistic people being less likely to move out and live independently due to apprehension of all of the change involved in doing so, or due to being unable to secure employment (a depressingly common problem) in order to have the income to do so. In my case, although I would love to live independently, I find the stigma of living at home to be infinitely preferable to the unpredictable sensory hell of living in an apartment with other people in the same room as me, above me, and adjacent to me.

Obsessive-Compulsive

Not to be confused with the more commonly known "obsessive-compulsive disorder" (OCD), which involves repeated and invasive compulsions and thoughts, "obsessive-compulsive personality disorder" (OCPD) involves an overwhelming obsession with control, perfectionism, small details, conscientiousness, and rules even to the detriment of actually getting tasks done on time, or at all. While someone with OCD may likely be haunted by their intrusive thoughts and compulsions, someone with OCPD will consider their controlling behaviours and ultra-rigid adherence to rules and routines to be completely normal and necessary.

OCPD can cause severe struggles with collaboration as a person may be unable to trust anyone to meet their standards, or simply unwilling to work with anyone who does not wholly submit to their ways of doing things. This can cause them to take on excessive volumes of work due to believing that they are the only person capable of doing it properly. They may also irritate anyone they work with via delaying projects by wasting time repeatedly combing over minutia.

People with OCPD are natural workaholics, and may consider personal activities such as vacations or hobbies to be a waste of time because they distract them from their work, or they may ruin leisure activities by being overly structured and rigid, criticising anyone who deviates from what they consider the proper way to participate in the activity. This rigidity extends to their moral values, as people with OCPD tend to adhere very strongly to their principles, regardless of circumstance, and will mercilessly judge anyone who does not live up to these same standards.

Difficulties in one's personal life are also common, as the need for control and perfectionism can extend to being a "control freak" in relationships and family life. In a superficial similiarity to SPD, people with OCPD also tend to be very reserved in expressing affection and other emotion, being quite stoic even when around a lover or a friend as their obsession with rigidity and rules can make them struggle with and be annoyed by the illogical world of emotions. Hoarding problems and an inability to throw out unneeded possessions, often to the annoyance of anyone who lives with them, are also often present due to worrying about waste or coming to need a useless item again in the future.

Virtually all of the symptoms of OCPD are common among autistic people, so it is no surprise that it also appears to occur quite often. While estimates for the prevalence of OCPD range anywhere from 2% to 8% in the general population, OCPD was detected in 32% of autistics (40% in those with Aspergers) in the 2009 study, and 19% in the 2012 study. Moreover, a 2018/2019 study done on OCD patients showed that 54.2% of those who also had OCPD, were also autistic.

No exact cause has been pinned down for what causes OCPD, with some theories suggesting that it may be genetic in nature, and others suggesting that it might be the result of child abuse that leads to an ingrained belief that a person has to be absolutely perfect in order to avoid punishment. It remains to be seen if there is any validity to these theories, but the latter one would certainly partially explain why it is so pervasive amongst autistics, since autistic children are quite prone to getting punished for breaking rules that they never intuitively learned like most neurotypicals do. I can recall numerous personal examples of being punished as a child for unruly behaviour that I had no idea was inappropriate at the time.

Both autistics and people with OCPD have a very strong need for routine, predictability, and control, especially when it comes to their personal space and projects, to the point of becoming stubbornly attached to minute details. Inflexible thinking is a key characteristic of both autism and OCPD, which contributes to the difficulties in collaborating with other people. There is a tendency to stubbornly believe there is only one very specific proper way to perform a task, and become upset if anyone does it differently or suggests doing it differently. This is only considered a symptom of autism/OCPD when the inflexible attachments to particular ways of completing tasks are irrationally stiff.

As an example, a person might be attached to a very specific way of marinating food and become outraged when they have to cook alongside another person and see them using a different method, even if it has no apparent flaws. For obvious reasons, these tendencies lead to autistics or people with OCPD wanting to avoid collaborating with or relying on other people, and simultaneously repels other people from wanting to work with them.

In my experience, there is some sort of "switch" that gets flipped when I consider the idea of allowing anyone else to collaborate with me on a project I have taken on, where I suddenly find myself seeing a person whose intelligence and competence I never previously doubted, as being too inept and useless to be allowed to help me with even the most basic of tasks, even while I am consciously aware of the absurdity of this thought. At work I had made a point of working hours late every day, refusing to take any breaks throughout the day, and never using any of my vacation time, simply to keep management from hiring another person to help because I was so haunted by the certainty that they would turn out to be a failure who would never live up to my standards.

I believe part of the reason I love working on this website so much, aside from having the opportunity to share and educate people on the causes and hobbies I am so passionate about, is the fact that I have complete control over every aspect of it (aside from the hosting) and do not have to fret endlessly over every little detail of the contributions of my hypothetical parter(s)-in-crime. Bast knows I already waste too much time going back, combing over, and looking for flaws or potential improvements in things I've made myself.

Autistic inertia is capable of provoking the same workaholic behaviour that OCPD is known for, allowing an autistic person to work without rest on a project until it's both finished and perfect, although it can just as easily lead to them wasting large amounts of time because they never managed to force themselves to start working. Notable difficulties with time management are present in both autism and OCPD and although autistic people struggle in general due to executive dysfunction, one common struggle is getting so utterly lost in picking away at one's work, that not only does everything else fall by the wayside, but the work itself may wind up being done late because of excessive nitpicking.

As a potentially humourous personal example of the latter, I am neglecting multiple important real life tasks while writing this because of how overwhelmingly I want to finish this article first. I initially meant to finish this article yesterday and work on my real life tasks today, but instead wound up spending hours chugging away on the Red Forest section after I suddenly had a vision for the design of the banner on top of the page, and found myself unable to stop myself from sitting there and putting the entire section together from scratch in one go. The autistic/OCPD work ethic can be thought of as a weapon that is exceptionally potent yet very difficult to aim with (and in the case of autism, sometimes impossible to activate to begin with!)

Additionally, as mentioned in the BPD part of this page, autistic people tend to stick to their principles very strongly and often have a very powerful sense of justice, to the point of being pathological, as they can go as far as ruining relationships simply to stick to their guns on a minor non-issue. People with OCPD can be much the same, and the DSM-5 notes for instance, that a person with OCPD may refuse to give their friend a quarter to make a phone call because they believe that it would be bad for their friend's character to be given money like a beggar.

While hoarding and refusing to dispose of unneeded or broken objects is common in both autism and OCPD, for autistic people it is usually due to sentimental attachment and a desire to avoid change in their environment. People with OCPD, on the other hand, have these tendencies because they are concerned about being wasteful or needing the object or some spare parts inside of it. Frugality and hoarding money in any way possible is also a symptom of OCPD, and occurs for much the same reason.

Conclusion

Research regarding autism as a whole, and its many intersections with personality disorders, is still evolving and much work still remains to be done. One pattern that has continually recurred throughout this article is that while there does not exist any consensus on what causes personality disorders, most of them are hypothesised to occur as a result of frequent negative childhood experiences.

I mentioned in my Intense World article that a study done on autistic rats showed that half of them did not display any outward signs of autism, including anxiety and withdrawal, when they were reared in an environment that was stable and accommodating to their needs. Although I firmly believe that there may be some genuine and inevitable overlap between autism and a few personality disorders (namely OCPD and possibly SPD), I suspect that the more dire ones, such as AVPD and BPD, could easily be preventable in most cases if autistic children are raised in an environment where their differences are accepted and their needs are accommodated.