Schizophrenia, Autism, and Sensory Processing

“During the last while back I have noticed that noises all seem to be louder to me than they were before. It’s as if someone had turned up the volume. . . . I notice it most with background noises– you know what I mean, noises that are always around but you don’t notice them. Now they seem to be just as loud and sometimes louder than the main noises that are going on. . . . It’s a bit alarming at times because it makes it difficult to keep your mind on something when there’s so much going on that you can’t help listening to”  (Description from patient with schizophrenia, from Torrey, 2001, p. 34).

Though they are considered distinct conditions, schizophrenia and autism have a shared past. At one point, many cases of autism were simply considered “childhood schizophrenia” and it was Bleuler himself who, in writing of the schizophrenic break from reality, popularized the term “autism”.

Some of their historical overlap is more than diagnostic gaffe however. While current research is addressing overlap of genetic and environmental risk factors, there are some similarities in terms of behavioral and cognitive symptomotology. Though the psychosis and delusions are probably schizophrenia’s most conspicuous symptoms, known otherwise as “positive symptoms,” the negative symptoms, e.g., executive dysfunction, blunted affect, monotonic and monosyllabic speech, disinterest in socialization, etc., tend to be the most debilitating.


Artwork by Chris Mars, who was inspired as a young boy by visits to a mental institution where his older 16 year-old brother was being treated for schizophrenia.

Alterations of the senses, according to Torrey (2001), also occur in the earliest stages of the illness in about 2/3rds of schizophrenic patients. The patient description given at the beginning of this blog seems particularly striking, describing a similar experience to those described by autistic people with auditory sensitivity. Obviously, the developmental progression is dissimilar, as autistic people are born with the propensity for sensory disturbances; meanwhile in schizophrenia, in what appears to be a regressive phenomenon, they acquire it. Nevertheless, there may be some functional commonality that produces this cognitive overlap in sensory experiences.

“Colours seem to be brighter now, almost as if they are luminous painting. I’m not sure if things are solid until I touch them. I seem to be noticing colours more than before, although I am not artistically minded. The colours of things seem much clearer and yet at the same time there is something missing. The things I look at seem to be flatter as if you were looking just at a surface. Maybe it’s because I notice so much more about things and find myself looking at them for a longer time. Not only the colour of things fascinates me but all sorts of little things, like markings in the surface, pick up my attention too” (Patient description, Torrey, 2001, p. 34).

Screen Shot 2014-08-17 at 4.04.01 PM

A fractal cat, painted by Louis Wain, who entered psychosis later in life and was committed at age 64. 

In fact, there is so much overlap between schizophrenia and autism that the two primary differences are psychosis and the fact that schizophrenia, though a neurodevelopmental condition, is regressive and exhibits traits of progressive degeneration. Alongside acuteness of the senses, sensory overload also occurs:

“Everything seems to grip my attention although I am not particularly interested in anything. I am speaking to you just now, but I can hear noises going on next door and in the corridor. I find it difficult to shut these out, and it makes it more difficult for me to concentrate on what I am saying to you. Often the silliest little things that are going on seem to interest me. That’s not even true: they don’t interest me, but I find myself attending to them and wasting a lot of time this way” (Torrey, 2001, p. 36).

For those who are well acquainted with autism, does this description sound familiar regarding attention and sensory gating seen in the spectrum?

“I can probably tell you as much or more about what really went on those days than lots of people who were sane: the comings and goings of people, the weather, what was on the news, what we ate, what records were played, what was said. My focus was a bit bizarre. I could do portraits of people who were walking down the street. I remembered license numbers of cars we were following into Vancouver. We paid $3.57 for gas. The air machine made eighteen dings while we were there” (Torrey, 2001, p. 36).

And this, reminiscent of the touch sensitivity many autistic people display:

“[It] was terrible to be touched. . . . Once a nurse tried to cut my nails. The touch was such that I tried to bite her” (Torrey, 2001, p. 39).

Schizophrenia and autism certainly seem like different conditions. Yet the traits they share suggest that there may be common ground as well, perhaps in terms of disturbances to connectivity and neuronal function. As such, it may be useful for researchers to study these conditions together, in the hopes that in understanding one, we may better understand the other. In any case, the overlap is curious and has certainly peeked my attention lately. Hopefully more on this topic later.

24 responses to “Schizophrenia, Autism, and Sensory Processing

  1. There are indications of increased prevalence of schizophrenia in ASD population – although there is not much pulished on the subject, one certainly gets that impression when speaking to clinicians who see lots of ASD patients – you hear claims that psychosis is ‘quite common’ in their HF ASD patient population. Which takes us to the crucial question of ‘how on earth do you diagnose schizophrenia in more severe, non-verbal ASD individuals ???’ (if a person is not capable of telling you they are hearing voices or experiencing body detachment, they might simply express themselves through odd behaviours, screaming or agressive attacks etc…) “The identification of psychiatric comorbidity is difficult in ASD patients: any psychiatric symptoms could overlap with or be masked by ASD symptoms themselves.”

    Similarly: “On the other hand, it was found that ASDs are much less recognized and diagnosed in those with milder core symptoms. HFA/AS patients may therefore present to health services for other psychiatric symptoms and these surface features may not clearly signal the presence of an ASD

    “… In our sample, 15.8% of patients presented psychotic symptoms, with onset in adulthood. In literature, the prevalence of schizophrenia in ASD is of 0.6% [11], in HFA/AS up to 3.3% [4]. In adults with schizophrenia, there is often a history of autistic symptoms in childhood;..”

    I strongly suspect the 0.6% figure is far too low and that most cases are simply missed (for reasons mentioned above), and that we can only blind guess the true prevalence and the extent of overlap of pathology (and etiology – not only genes but prenatal infections are implcated in both!) in ASD and schizophrenia.

    btw I wouldn’t necessarily agree that ASD kids are ‘born with the propensity for sensory disturbances’ – remember that over 1/3 of autism is of regressive type – in many of these cases, or most of them, we could be looking at the same situation as in schizophrenia, where the sensory disturbances are simply acquired alongside other neurological etc dysfunctions. (or if we insist and maintain that some sort of ‘propensity’ or risk factor must have been there all along in regressive ASD types, then the same could be claimed for schizophrenia…)

    PS thought you might be interested in this publication

    • True re regressive autism, I generalized too much considering early regression “early enough”. In either case though, the point is that the propensity is there from very early on, whereas with most cases of schizophrenia, this degeneration doesn’t occur until the premorbid stage just prior to the first episode, typically in late teens or adulthood.

      Truthfully, I’m not certain about schizophrenia and autism comorbidity. I have definitely heard reports of increased psychosis in ASC, but in general a true schizophrenic break doesn’t seem to be common. Admittedly, there is the unanswered question of “What would schizophrenia look like in an autistic person?” if autism already displays a number of cognitive aspects that occur in the schizophrenic breakdown, e.g., sensory issues, altered memory capacity, attention to details, etc.

      Autism and epilepsy share some considerable comorbidity, to the point that they probably have a LOT in common etiologically. The queer thing is that, although genetically there’s some significant overlap between epilepsy and schizophrenia, their comorbidity is quite rare and no more than the risk of the general population. Psychiatrists used to believed that epilepsy was a protective factor against schizophrenia, having noticed low comorbidity rates and also improvement in sz symptoms with electroconvulsive therapy. That seems to have been disproven and the rates are simply very low. But, since autism and epilepsy share excessive overlap, not only at the hereditary level but also at the structural and physiological level, alongside high comorbidity rates, it likewise suggests that, at a very basic level, autism and schizophrenia have some very distinctive differences. Too early to tell what those are though.

      On the other hand, autism may have more in common with early onset forms of schizophrenia, as there seems to be overlapping genetic risk, similarities in structural brain abnormalities, and higher comorbidity. 22q11 deletion syndrome is an excellent example of early risk for psychosis and high rates of autism dx.

    • “btw I wouldn’t necessarily agree that ASD kids are ‘born with the propensity for sensory disturbances’ – remember that over 1/3 of autism is of regressive type ”

      Just out of curiosity, why wouldn’t sensory disturbances be a part of regressive autism? I don’t think I have ever heard of, met, or read about a person with autism who didn’t have sensory issues as part of the core of their autism.

      In my own family I have daughters with autism who both regressed and didn’t regress. The ones that regressed have more sensory issues and those sensory issues are one of the few symptoms that predated the regression. It is the one who didn’t regress that didn’t show any signs of sensory issues until later on.

      • Ah no, I didn’t mean that regressive autism doesn’t have sensory disturbances. I just grouped both typical and regressive autisms together because they both occur so early in development that the sensory issues, as well as everything else, are present at least from toddlerhood. Whereas in sz, the active symptoms of the condition are acquired over time– although there’s also the concept of a schizophrenia spectrum and that lighter variants of some of the same symptoms can be seen much earlier.

  2. One thing that I find interesting is that it is apparently hard to tell the difference between schizophrenia and HFA, especially in adults. I don’t know that much about schizophrenia but I have seen several papers over the years that talk about how it is difficult to differentiate between the two conditions.

    For example take this one – – that was looking at whether the Autism Quotient can be used to differentiate between the two conditions and finds that it cannot do so reliably. The paper also talks about how the symptoms of the two conditions have significant overlap. Such as how the social withdrawal in autism can be mistaken for the negative symptoms of schizophrenia.

  3. Thanks for the paper, MJ. I hadn’t read that one before. Yes, I had heard similar things in the past re negative symptoms of schizophrenia and autism. Which undoubtedly provides some confusion in discerning just how much autism and schizophrenia may overlap comorbidly.

    I have also heard of psychosis occurring more in autism than is typically acknowledged; however, I suspect, based on anecdote of personal stories, that the psychosis may not be quite schizophrenic-like in nature, including fullblown hallucinations, but may instead be milder delusions and dissociation from reality. If that is indeed the case, I think that’s important to note because fullblown hallucinations, delusions, thought disorder, etc., are some of the hallmark features of that kind of schizophrenic regression and subsequent, yet subtle, neurodegeneration. In short, they may indicate some important differences in the processes– or perhaps in the trajectory of development– between autism and schizophrenia.

  4. My son whom is 22 is caught in this dilemma. I feel he is being shown a great disservice as he is being medicated for a disorder which according to research I have found is the wrong choices for treatment. They say schizophrenia & I say autism. We have fought this fight since age 12 when he rec a dx of PDD-NOS (because he was over 3 they said they couldn’t dx autism, even though he fit the criteria) & schizophreniform DO. When he gotr the 2nd dx notes from the dr say he was started on anti-psychotic but staff does not see any change but my son said he felt better. I think the sensory overload was more the changing factor than the drugs, always have please help!!!!!

    • That’s a tough one, Linda. First off, if his sensory overload/anxiety is one of his bigger issues and the antipsychotics seem to be helping that, then he could maybe benefit from a lower dose antipsychotic as is used with autism. I’d imagine they’re probably giving him higher doses due to the sz dx. For one thing, it sounds like your son needs to seek treatment from someone else, perhaps getting a second opinion from a local autism center. Is he willing to listen to you and take your advice?

      As you probably realize, antipsychotics can reduce positive symptoms in schizophrenia, but then they can also just act as sedatives in just about anyone. If he’s being helped as you say, it sounds like it could simply be the sedative effect, in which case there are better meds and dosages out there than are typically given to someone with schizophrenia.

      • They are giving him anti-psychotics related to their dx. He also went catatonic for 34 days when they did this less than 9 months ago,The current dr’s won’t recognize the catatonia dx even. He has extreme anxiety & PTSD. They acknowledge that as hx only. They make no mention of severe anxiety. but is a different hosp. He is starting to report muscle tightness & nausea. He also is having increased lapses in communication. They gave him Zyprexa Zydis which has been listed as a allergy/poor response & he had a major meltdown with aggression. They transferred him to their most secure ward. He is increasing in stress & I worry that they will view his increasing stress as psychotic behavior as I figured out that the charge nurse their didn’t know what stimming was & they interpret that to be AH & responding to internal stimuli. I will cash in my 401 k if you can recommend me to an expert in diagnostics of both autism & schizophrenia to get a clear definitive dx. any suggestions. I will travel if needed even.

  5. Sadly I don’t know whom I could refer you to. But I would recommend seeing if there are any autism centers locally, calling them, and asking whether there’s any diagnosticians in the local area who are experienced working with adults. Give the center a brief rundown of your son’s situation and see what they might recommend. Hopefully they would have more ideas than myself. Unfortuntely, as a researcher I don’t have as many connections to the clinical realm in order to be able to help you. But I would say keep calling around and searching until you find somebody with experience who will listen to your concerns and be able to give you more pragmatic advice than I can give. Best of luck and let me know how it goes, Linda.

    • thank you.. My son is connected to the Autism Society of Mn. Unfortunately the medical dr’s don’t want to talk to the autism
      Dr as she does not have a medical degree it seems. everyone seems to sympathize with my situation but there is no one whom is there to help. but thank you for at least getting back to me.

      • If you have guardianship over your son or if you can convince him otherwise, I would recommend you find your son another doctor, someone who is willing to work with you guys, rather than against you. This is a psychiatrist you’re referring to I assume? Would it be possible to continue doctor shopping?

      • I am trying to do that. I am trying to find an expert first to refute or confirm the diagnosis. I have numerous calls/e-mails to dr’s all over the country. Do you have any recommendations to get a diagnostic done first?

      • I’m wondering if it isn’t better to first get your son away from this particular doctor and then go in search for a new doc in order to deal with diagnosis. Would that be possible? If you can at least find a doctor who will listen to your concerns, you don’t necessarily need an autism expert right away. You primarily need someone who is open to exploring alternatives and who will work gently with your son. Perhaps such a clinician could then help in the search for an expert if you still find it necessary.

      • this has been an ongoing fight for 10 years… I have had dr’s say that his delusions don’t fit the typical schizophrenia type seen but then he will end up in the hosp & like I recently realized the staff see his stimming*a trait of autism) as responding to Auditory Hallucinations. The next thing you know they say schizophrenia…. I am at my wits end. It seems they blame me for the catatonia thinking I withheld his meds when he was on the stay of commitment & that is whet the catatonia happened. Even though prior to the stay agreement I said clearly many times that if they cont to treat for a condition he doesn’t have that would be the result. I do have a witness that I gave the meds as they were ordered despite my opposition to them. Do you know of anyone. I am willing to cash in my 401 & travel to find appropriate treatment.

      • I genuinely don’t know who I could recommend you to. But do you need a recommendation to get him away from the “care” of these particular doctors? I would recommend to go doctor shopping beforehand and find somebody who’s willing to listen and work with you and your son. That’s the important part at this stage it sounds like. You can change his doctors. Or at least he can. But if you’re waiting to find an expert, you might have an even longer wait. It might be better to simply find another clinician who is willing to work with you rather than hand down diagnoses from on-high. Does that make sense? It would be easier to find such a diagnostician than to find an expert in your son’s particular situation. Finding somebody who knows autism, adolescence, and psychosis is going to be a challenge.

      • thank you for always responding to me. I feel like a problem child…lol. I found a web site through a schizophrenia that is in CA & doing research in this area. I will contact them. I thought after his catatonia & changing dr’s to the one recommended from the dr who treated his catatonia we had that. He was in a week before stress (numerous) happened & he was brought to the hosp that did the commitment * put back on drugs. She saw he was starting a work eval & doing great. He has had 6 hospitalizations since they did the drugs but apparently is not able to look at the picture as the change was drugs & stress that was the factor & like I said they view his stimming as responding to AH so he must be psychotic & schizophrenic. I feel so defeated & not until my son goes completely non-verbal, non-functioning or possibly dead maybe then they will listen ….. thanks for your assistance & support It is greatly appreciated ….

    • I think I may have found a group. It is looking like my son & myself will be going to the the University Of California San Diego in Feb. They are coming up with what the plan will be to look at the diagnosis & do testing ect to establish a accurate picture of my son. Thank you so much for your support… it allowed me to keep plugging away & not just give up defeated…:’)

      • Hey, that’s awesome, Linda! 🙂 I wish you both the best of luck. Hopefully this is the break you were looking for. Let me know how it goes. And I’m glad I could be of some support for you.

  6. I’m happy to help, Linda, although I’m sorry I can’t give more of it. Contacting the researchers in California sounds like a good idea. Hopefully they might have more connections than I have. 🙂

  7. I think it may be useful when supporting a child with ASD to consider that: The usual notions of what is real and not real are not assumed; that due to anxiety from theory of mind differences, what people are capable of doing (against someone) are not assumed and even a loving partner of parent/care giver cannot intuitively be trusted and their love not assumed; that without the context that typically enables people to generalise and view events or signs, even the most innocuous things can loom terrifyingly and disproportionately: The plaque warning “you” to cover your pin number at the cash-point because “someone could be watching” for instance,,,

    If a child has a developmental condition, how can we tell if their symbolic world and the world we are taught to live in is developing in a typical way? Are we able to support a child in a way which respects these neurological differences as healthy if supported appropriately rather than a disease or set of behaviours? There are so many aspects of ASD which are not understood very well and so many perspectives which can lead to interventions which border or repressive and unethical.

    Is it possible that social communication differences affect how a person communicates with their “inner self”?

    Is it possible that sensory processing and anxiety could impact in an adverse manner, giving the affected person a type of hallucinatory experience?

    How is a person affected when they also have a different experience of themselves as a separate and united self or identity?

    These are all questions which I would like to explore, and I appreciate your thoughts and comments found here.


Leave a Reply

Please log in using one of these methods to post your comment: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s