Symptoms of ASD in Adults: What to Look Out For

While most people with Autism Spectrum Disorder (ASD) are diagnosed as children, for various reasons, many people are not diagnosed until adulthood. One of these reasons may be that symptoms of ASD were masked whilst growing up. Many high functioning children with ASD can be exceptionally intelligent and well functioning at school. To parents and teachers, their exceptional abilities may mask other behavioural signs of ASD. Another reason may be mis-diagnosis. Many symptoms of ASD may present similarly to other neurodevelopmental disorders or mental health difficulties such as Attention Deficit Hyperactive Disorder (ADHD) and obsessive compulsive disorder (OCD). These early mis-diagnoses are sometimes not noticed until adulthood.

Although not receiving an ASD diagnosis at a young age could mean that the child misses out on imperative learning support, it is never too late. Receiving an ASD diagnosis as an adult can be very beneficial. As an adult, it may be relieving to finally understand your behaviour and preferences. In addition, you can access ample support to help you understand your diagnosis, learn how to helpfully communicate your diagnosis to others and learn how to manage better if certain situations are particularly problematic for you.

Autism is considered a spectrum because each person will present very uniquely. The signs of autism can vary significantly between children and adults and even between men and women. However, there are a number of common signs that you can look out for, if you are considering an ASD diagnosis for yourself or another adult. In this blog we will list and explain signs of ASD in adults.

Different Kinds of ASD Symptoms in Adults

Autism is characterised as a developmental disorder that affects social and communication skills, as well as how people interact and understand the world around them. Symptoms of ASD in adults tend to be grouped into three main areas.

  • Perception and interaction with the world and others: Adults with ASD may perceive certain environmental stimuli differently to their neuro-typical peers due to sensory sensitivity. In addition, adults with ASD may not always understand social cues or how others are feeling.
  • Communication difficulties: Adults with ASD may process and verbalise language and information differently to their neuro-typical peers. This might make an adult with ASD appear blunt in their communication and they may struggle to understand metaphors and analogies, often preferring literal language.
  • Repetitive and rigid patterns of behaviours: Adults with ASD may thrive from routine as uncertainty can be quite overwhelming. They may show a distinct preference for a certain way of doing things and appear reluctant to change.

Although there are three main categories of ASD symptoms, it might be that an adult with ASD does not present with symptoms in all three categories and may notice more symptoms in only one or two of the categories.

What to Look Out For: The Most Common ASD Symptoms in Adults

Now, let’s take a look at the most common signs of autism that may fall under the three categories mentioned above.

  • Due to having a more sensitive sensory system, some people with autism may struggle to be in situations where certain senses are over-stimulated. These might be places with loud sound, for example busy restaurants and concerts, or places that are highly visually stimulating with lots of bright colours. In addition, adults with ASD may have a preference for certain situations that stimulate their sensory system enough to feel good but not too much that it is overwhelming; they may have a strong preference for certain colours that are calm and soothing and certain textures too.
  • For various reasons, social situations can be anxiety- provoking for adults with ASD. One of these reasons might be the over-stimulation, but they may also notice themselves struggling when it comes to connecting with others in the same way their neuro-typical peers do. Adults with ASD can struggle to interpret facial expressions, understand body language, and decipher gaze direction. This may result in experiences where the adult with ASD has felt judged or different compared to others, and these thoughts can tend to trigger anxiety.
  • Some adults with ADHD can struggle to understand the symbolism behind figurative language and can tend to take things quite literally. Although many adults with ADHD can learn to respond in a socially expected way to figurative language, it may not come naturally due to the way their brains process language.
  • Adults with ASD may have a fairly inflexible routine as routine can be very cathartic. The need for structure and certainty can become more apparent in adulthood as the day becomes more flexible than the highly structured day that comes with going to school. Adults with ADHD might experience distress when their plan or structure is thrown off course, for example if they have been made late to attending something or their living circumstances change.

Other Symptoms of ASD in Adults

Aside from the main symptoms of autism, there are a number of other signs that you can look out for. None of these signs, or those above, should be taken as proof of autism on their own, but as an indicator to explore more.

  • Unspoken social “rules” might not be clear to adults with autism, which may mean they find themselves talking over others and struggling with the give-and-take nature of a natural conversation. Eye contact may also be difficult to maintain for adults with ASD, which to others, may make it seem as though they aren’t interested in the conversation at hand.
  • As aforementioned, adults with ASD will often experience sensory sensitivity, which makes them more susceptible to noticing sensory details in their environment, such as smells and sounds that others might not notice. Too much of an unpleasant sensation can be catastrophic to an adult with autism, however, often adults with ASD will adapt self-soothing behaviours to help them cope better. Engaging with these behaviours repetitively is called “stimming”: a way of using repetitive behaviour to self-regulate emotions.
  • People with autism often have one or two special interests: topics that they are highly focused on. They can be as narrow as a favourite character, or as broad as a long-running TV show. Some may even have a special interest in an action such as taking things apart. These special interests can be incredibly beneficial for people with autism as they can provide structure and help to connect with others with similar special interests.

While there are many symptoms of ASD in adults that you can look out for, it’s always important to remember that stand-alone symptoms can’t always dictate whether someone has autism. There are many other reasons why someone might be demonstrating any of these behaviours.

If you are recognising these symptoms and want to look into getting an ASD diagnosis, you can book a consultation with one of Psymplicity Healthcare’s experts today to book a private autism assessment an Getting a confirmed diagnosis of autism will allow you to get access to the support and services you need to help manage your symptoms, and experience more from life without anxiety.
Mavish S

Mavish S

Mavish is a BABCP Accredited CBT and EMDR Therapist and CBT Clinical Lead at Psymplicity. Since beginning undergraduate studies 13 years ago, Mavish has worked in various mental health settings within the charity, NHS and private sector. Mavish’s passion for learning and professional growth has led to a vastness of experience and accelerated growth in her career while delivering one-to-one therapy, group workshops, training and supervision for professionals and senior team management. Mavish is a keen writer and writes many of the articles on our website, as well of our self-help resources.

View Author Page

Speak with an experienced medical secretary

Book an assessment and attend your appointment from the comfort of your home.


Latest posts:

Child Autism Test

Share this post:

Do you need support managing the mental health symptoms dominating your life?

Get in touch today to have a no-obligation call with one of our medical secretaries.