Is There A Relation Between Autism And Schizophrenia?

Autism spectrum disorder (ASD) is a condition that disrupts the ability of a person to communicate and interact with others. The condition is related to the development of the brain, and it affects how a person perceives, socializes, and interacts with others. It not only causes problems in social interaction but also in communication with others and includes restricted and repetitive patterns of behavior. The reason the disorder is known as autism ‘spectrum’ disorder is that it refers to the wide range of symptoms and severity of the condition.^{(1, 2, 3, 4)}

Autism includes conditions that were earlier considered to be separate, such as Asperger’s syndrome, childhood disintegrative, childhood disintegrative disorder, an unspecified form of pervasive developmental disorder, and of course, autism.

On the other hand, schizophrenia is a type of serious chronic mental disorder. People with this condition experience distortions of reality, typically in the form of delusions and/or hallucinations. According to the American Psychiatric Association, it is estimated that schizophrenia affects less than one percent of the population in the United States. Apart from experiencing a combination of delusions and hallucinations, people with schizophrenia also cause extremely disordered behavior and thinking that affect day-to-day functioning. This prevents a person from leading a normal life.^{(5, 6, 7)}

Autism and schizophrenia are two different conditions, but they share many symptoms and both impact how the brain develops. At the same time, there are some key differences between the two that you should be aware of in order to receive a correct diagnosis.

According to the National Institute of Mental Health (NIMH), autism spectrum disorder is defined as a spectrum disorder since the symptoms of this disorder vary a lot from person to person. Two of the main symptoms of autism include:⁽⁸⁾

• Challenges in communicating or interacting in social situations.
• Restricted and repetitive behaviors.

According to a review carried out in 2019, many researchers consider schizophrenia to also be a spectrum disorder due to the wide variation in symptoms.⁽⁹⁾ The National Institute of Mental Health says that schizophrenia must be diagnosed on the basis of the following:⁽¹⁰⁾

• Cognitive impairments
• Negative or missing symptoms
• Symptoms of psychosis, such as delusions and hallucinations

People with schizophrenia may also experience some symptoms that are commonly observed in autism spectrum disorder.⁽¹¹⁾ However, a study from 2018 revealed that autistic people are nearly 3.55 times more likely to also get a diagnosis of schizophrenia.⁽¹²⁾ However, this does not mean that an autistic person will definitely or automatically go on to develop schizophrenia or vice versa.

Autism spectrum disorder and schizophrenia are believed to have a genetic link. Some disorders are caused by certain changes to our chromosomes, which are the molecules that carry our genetic code. A study from 2017 showed that a deletion on chromosome 22 could lead to the development of some disorders, including schizophrenia and an autism spectrum disorder.⁽¹³⁾

Another study from 2017 found that both these conditions are unlikely to develop together.⁽¹⁴⁾ Scientists have found that autism spectrum disorder and schizophrenia might be two different outcomes that stem from the same genetic syndrome.

Another 2021 study also suggested that children of parents who have schizophrenia are at a greater risk of having autistic traits.⁽¹⁵⁾ These findings lend support to other older studies that also showed that children of parents with schizophrenia were three times more likely to also receive an autism diagnosis.⁽¹⁶⁾

However, it is necessary to keep in mind that studies done so far have been on small sample sizes. This is why more research is needed to fully comprehend how genetics influence schizophrenia and an autism spectrum disorder.

Both autism spectrum disorder and schizophrenia are known to be neurodevelopmental disorders. This means that both conditions affect how the brain develops. With the use of brain imagining, medical experts have been able to see the similarities between the brains of those with schizophrenia and autism.

According to a 2018 study, some of the similarities include:⁽¹⁷⁾

• Change in white matter in the brain, which are the deeper brain tissues where the connections of the brain are made.
• Decrease in gray matter, which is the outer part of the brain where primary processing takes place.
• Decreased activity in those parts of the brain that are related to language and social interactions.

Symptoms of both schizophrenia and autism spectrum disorder are grouped into three different categories, including:

• Positive
• Negative
• Cognitive

There are some symptoms that are observed in both conditions and some symptoms that are unique to each of these illnesses. Let us take a closer look at these symptoms and what these terms mean.

Positive symptoms refer to those symptoms that are present in people with the condition but are not present in neurotypical people. Neurotypical is a term used to refer to people who have typical neurological functioning.

Positive symptoms of autism spectrum disorder and schizophrenia are unique to each disorder. These symptoms are considered to be the simplest way to distinguish between the two conditions. Positive symptoms also vary quite a lot from person to person. However, according to a study carried out in 2020, there are some positive symptoms that are common to both conditions.⁽¹⁸⁾ These include:

• Concentration issues
• Difficulty processing information
• Trouble interacting socially
• Difficulties in motor function
• Unusual thinking patterns
• Trouble with social communication
• Trouble with relationships

Negative symptoms refer to the absence of ‘normal’ functions and are present in most people but absent in people who have these conditions.

Negative symptoms of autism spectrum disorder and schizophrenia are often quite similar. Studies have shown that these similarities tend to affect emotional interactions and communication with others.⁽¹⁸⁾ These may include the following:

• Having a ‘flat’ tone of voice
• Perceived inability to express or identify emotions
• Reduced eye contact
• Lack of facial expressions
• Perceived apathy
• Reduced speech
• Decreased physical movements
• Social withdrawal
• Lack of social interest

Cognitive symptoms are described as an impairment of understanding, memory, and concentration. This can impact a person’s ability to learn or complete tasks. Just like negative symptoms, schizophrenia and autism spectrum disorder have several of similar cognitive symptoms. However, cognitive differences in people with schizophrenia have been observed to be more severe.

According to a review done in 2019, some of the cognitive abilities that are likely to be different in both the disorders include:⁽¹⁹⁾

• Attention
• Processing speed
• Visual learning
• Verbal learning
• Spatial perception
• Working memory
• Reasoning and problem solving
• Language comprehension

In a study done in 2020, people with schizophrenia have much more severe impairments across the board as compared to autistic people. This is especially found to be true when it comes to language, perception, working memory, and reasoning.⁽²⁰⁾

In order to make the correct diagnosis, it is important to be aware of the differences between schizophrenia and an autism spectrum disorder. It is essential for family members also to be mindful of these differences as this can help you get a correct diagnosis and also connect you with helpful therapies and interventions.

It is also important to keep in mind that there is a possibility of many other conditions also co-occurring with either schizophrenia or autism. Many of these conditions as well share similar symptoms, and this further increases the chances of misdiagnosis.

For example, in 2020, a study found that autism spectrum disorder can co-occur with the following other conditions:⁽¹⁸⁾

• Depression
• Anxiety
• Attention deficit hyperactivity disorder (ADHD)
• Tic disorders
• Intellectual and developmental disorders

On the other hand, schizophrenia may co-occur with:

• Depression
• Anxiety
• Panic disorders
• Obsessive-Compulsive Disorder (OCD)
• Substance use disorders
• Post Traumatic Stress Disorder (PTSD)

Autism spectrum disorder is usually diagnosed during a wellness exam or annual checkup of a young child with their pediatrician. The pediatrician is likely to ask the child’s caregiver several questions about their development, including their communication skills and speech. They will also ask if the child displays any repetitive and restricted behaviors.

Autism is a complex condition, and your pediatrician is likely to refer them to other professionals for further evaluation:

• Pediatric neurologist
• Child psychiatrist or psychologist
• Neuropsychologist
• Occupational therapist
• Speech-language pathologist

A mental health professional typically makes a schizophrenia diagnosis after a person experiences symptoms of psychosis, like hallucinations and/or delusions. During the diagnosis of schizophrenia, a doctor is likely to focus less on developmental stages and social-communication skills.

In schizophrenia, the first episode of psychosis is likely to occur during late adolescence or early adulthood. However, most people with schizophrenia are likely to experience some symptoms, like thinking and mood changes, as early as mid-adolescence.

In some very rare cases, doctors diagnose schizophrenia in someone who is younger than 13 years. This is known as childhood-onset schizophrenia (COS).^{(21, 22, 23)}

According to a 2019 review, it is estimated that less than 1 in 40,000 children develop this condition.⁽²⁴⁾ This condition is so rare that it is not clearly understood and is very difficult to diagnose.

Some of the early negative symptoms in childhood-onset schizophrenia look similar to those of autism, and in fact, until 1980, autism itself was known as childhood schizophrenia.⁽²⁵⁾

It is also difficult to identify the positive symptoms of childhood-onset schizophrenia. Some of the childish behaviors might be confused for psychosis. It is even more challenging to diagnose this condition because children themselves cannot describe their own symptoms to the doctor.

Before the positive symptoms start to show up, some warning signs are usually apparent. As per a 2014 study, these signs may include:⁽²⁶⁾

• Loneliness
• Shyness
• Aggression
• Depression
• Theft
• Bizarre behavior
• Thoughts of suicide

It is necessary to realize that using the term treatment for autism spectrum disorder is subjective because there is only therapy available for autistic people that helps them feel better and function better in social situations, schools, and work.

Interventions for autism are likely to begin from a young age itself and also include a combination of the following therapies and support:

• Behavioral therapy
• Occupational therapy
• Social groups
• Speech therapy
• Educational support, including an individualized education plan (IEP) at school
• Medications to help treat aggression, anxiety, and any other concerns

Treatment for schizophrenia typically revolves around therapies and medications. These include:

• Antipsychotic medications that help treat the symptoms of psychosis.
• Cognitive-behavioral therapy to help address the negative symptoms.
• Psychosocial therapies that help improve coping skills to allow greater participation in school, work, and overall social situations.
• Assertive community treatment that supports people with homelessness or repeated hospitalizations.
• Coordinated specialty care that combines medications and therapies for designing a comprehensive treatment approach.

Both autism spectrum disorder and schizophrenia tend to develop at a young age. This is why therapies and any other treatments are most effective if they are started at a young age itself.

The symptoms for each condition differ quite a bit from person to person, and this is why the outlook also varies with each person.

Autism is a lifelong condition, though early interventions can increase the chances of achieving more independence in adulthood.

The outlook for schizophrenia is also equally varied. Some people go into remission from their symptoms, while others continue to experience symptoms, or they might go through periods of recurrence and remission. According to the World Health Organization (WHO), it is estimated that one in three people recover fully from schizophrenia.⁽²⁷⁾

Autism spectrum disorder and schizophrenia are two separate conditions that share some similar symptoms, especially when it comes to communication and social interaction. However, despite the similarities between their symptoms, schizophrenia, and autism are two separate conditions that also have their unique symptoms.

It is important that you avoid doing any self-diagnosing. Getting a professional diagnosis is essential to start suitable therapies and other treatments.

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