Sensory overload is when one or more of the body's senses is overstimulated to a point where a person is unable to cope. It is a term commonly associated with autism but can also be applied to anxiety disorders like post-traumatic stress disorder (PTSD) and obsessive-compulsive disorder (OCD).
People on the autism spectrum can be sensitive to their environments and have unusually delicate sensory systems. This means that their senses—sight, hearing, touch, smell, and taste—can be easily overloaded.
Unlike neurotypical people (people without autism), people with autism are often unable to selectively filter out environmental stimuli like car alarms or the clamor of a crowd. This can lead to behaviors such as "stimming" that help people with autism better cope with stress and sensory overload.
This article explores the symptoms and causes of sensory overload. It also covers what can be done to ensure the right level of sensory stimulation for a loved one with autism.
Symptoms of Sensory Overload
Sensory overload is a type of sensory processing disorder (SPD). SPDs are conditions in which a person does not respond normally to environmental stimuli, either because they are over-responsive (sensory hypersensitivity) or under-responsive (sensory hyposensitivity).
Sensory overload is most common in children with autism and attention deficit hyperactivity disorder (ADHD). It can also affect adults with autism, including those with high-functioning autism.
In some cases, the hypersensitivity may be so extreme that a person will react to sensations that others may not even recognize (such as a smell or the fluttering sound of a fan).
Sensory overload can trigger extreme symptoms in people with autism, including:
- Anxiety and fear
- Irritability or anger
- Muscle tension
- Increased heart rate
- Rapid breathing
- Extreme sweating
- Covering the ears or eyes to block out the stimulus
- Not wanting to be touched or approached
- Self-harming behaviors
Sensory Overload and Stimming
In people with autism, one of the classic responses to sensory overload is stimming (self-stimulatory behaviors). These are repetitive behaviors that are both distracting and self-soothing. Examples include hand-flapping, rocking, repeating words or phrases, or sitting on the floor and spinning.
In extreme cases, stimming can cause self-harming behavior like head banging, ear-clapping, self-scratching, or self-hitting.
Signs and Symptoms of Severe Autism
Other Possible Responses
People who witness an autism meltdown will often regard it as a "tantrum" or assume that it came out of nowhere. This is because the responses are not always the same and can differ from one situation to the next.
For example, a child with autism may respond differently to flickering lights at school than to flickering lights at home. Or, they may be hypersensitive to high-pitched noises but completely oblivious to booming, low-pitched sounds.
Moreover, while stimming is a common response, there are other possible reactions a person with autism may have, including:
- Sensory-seeking behaviors: Such as sniffing objects or staring intently at moving objects
- Sensory-avoidance behaviors: Escaping everyday sounds, sights, or textures
- Distraction behaviors: Engaging intensely with a favorite sensation
How Autism Meltdowns Differ From Tantrums
Causes of Sensory Overload
The cause of SPDs is poorly understood and can differ based on whether a person has autism, ADHD, PTSD, or other developmental or psychiatric disorders.
What is known is that children with autism typically lack social attention, meaning the awareness of social cues and the expected modes of social interactions. On the flip side, they will often be hyperattentive to objects or environmental stimuli that others either filter out or fail to notice.
This imbalance in attention and the inability to shift focus between the larger environment and smaller details may account for why 95.8% of children with autism experience SPDs, according to a 2020 study in the Frontiers of Integrative Neuroscience.
The types of stimuli that trigger sensory overload can also vary from one person to the next. They may include:
- Sounds: Especially persistent sounds like lawnmowers, washing machines, ticking clocks, or dripping water
- Sights: Such as a flickering fluorescent lamp or curtains that flutter
- Smells: Particularly heavy or distinct smells such as cleaning supplies, perfumes, new carpets, or foods
- Textures: Such as eating slippery foods or touching a slimy gel
Other Types of Sensory Overload
Sensory overload is not limited to the five main senses. A person with autism may also overreact to three additional senses that impact a person's balance, motor skills, and body awareness.
The additional senses are referred to as:
- Vestibular: This refers to structures in the inner ear thatdetect movement and changes in the position of the head. The vestibular system can tell you, for example, when your head is upright or tilted even when your eyes are shut.
- Proprioception: This refers to understanding where your body is in relation to other objects. The proprioceptive system is made up of receptors in muscles that monitor muscle length, tension, and pressure.
- Interoception: This is the recognition of what is going on inside your body, such as knowing when you are hungry, full, hot, cold, or thirsty. The interoceptive system involves a network of cranial nerves that interprets changes in the digestive tract, blood vessels, and other organ systems.
These senses can be overloaded in the same way that sound, sight, touch, smell, and taste can. In people with autism, this can lead to balance and coordination problems in addition to the more common symptoms of sensory overload.
Managing Anxiety in People With Autism
How to Manage Sensory Overload
Ensuring the right amount of sensory input—not too much and not too little—is important to the physical and emotional well-being of a child or adult with autism.
As the parent, guardian, or caregiver, it is important to recognize signs and symptoms of sensory overload. That way, you can act swiftly or appropriately when it occurs.
- Being watchful of the signs of distress before your loved one has a meltdown.
- Encouraging your loved one to communicate what is causing frustration, anger, or agitation so that you can remove the offending trigger.
- Asking what would help them feel calm, such as a change of environment or even a nap. Consider getting a weighted vest or blanket that may provide a sense of calm and security. Even a favorite stuffed toy or pillow can help.
- Making time for regular exercise to help burn off pent-up energy or stress. For children, an outdoor swing not only offers stimulation but can also be used as an outlet for stimming behaviors.
- Teaching older children meditation or other self-calming techniques, such as deep breathing exercises, yoga, or guided imagery.
Occupational therapycan help people with SPDs acquire or regain the skills essential to daily life.
One technique commonly used in children is called sensory integration therapy (SIT). It involves exposing a child to different stimuli in a safe, play-based environment to gradually reduce their hypersensitivity.
Occupational therapists may employ other tools to reduce the risk of sensory overload:
- Sensory adaptation: This involves tools that block out environmental stimuli, such as earplugs, noise-canceling headphones, or a white noise machine.
- Environmental modifications: This may involve soundproofing a room, changing artwork, or changing textures to decrease stimulation.
- Sensory diets: This is a tailored strategy to ensure the right level of stimulation. This may involve weighted blankets, fidgets or stress balls, scheduled daily activities, and the creation of a quiet space.
Medications are less commonly used to treat sensory overload in children with autism. Even so, they may be appropriate if the overstimulation is causing extreme or self-harming behaviors.
The antipsychotic drugsRisperdal (risperidone)andAbilify (aripiprazole)are two drugs that are sometimes prescribed to children or adults with autism. Both can reduce irritability and aggressiveness, which can fuel excessive stimming behaviors.
If there are signs of ADHD, which often occurs in children with autism, medications such as Tenex (guanfacine), Straterra (atomoxetine), and Ritalin (methylphenidate) can also be prescribed.
How to Calm a Child With Autism
Are There Tests to Diagnose Sensory Overload?
Diagnosing sensory overload can be difficult as there are no official criteria for the condition in the American Psychiatric Association's Diagnostic and Statistical Manual for Mental Disorders (DMS-5).
Even so, there are tests called the Sensory Integration and Praxis Tests (SIPT) that are used to diagnose SPDs. Used in children between the ages of four and nine, the SIPT consists of 17 tests that evaluate a child's response to sensory stimulation, balance, coordination, posture, and eye movements.
While useful in diagnosing sensory processing disorders, SIPTs are not used to diagnose autism or any other developmental or psychiatric disorder.
How Autism Is Diagnosed
When to See a Healthcare Provider
Sensory overload can cause considerable stress to people with autism as well as their loved ones. In general, meltdowns and stimming behaviors are often more distressing than dangerous and, as such, don't require immediate medical care.
However, medical treatment may be needed if behaviors are causing undue distress, disruption, or any risk of self-harm or harm to others.
Speak with your loved one's mental healthcare provider to understand the benefits and risks of treatment. That way, you can make an informed choice as a parent or guardian.
It is not uncommon for children with autism to be abnormally sensitive to certain sights, sounds, tastes, or textures. The condition, known as sensory overload, is not exclusive to children with autism but tends to be more common and severe.
Coping skills include recognizing the signs of a meltdown before it occurs. Occupational therapists can help you find ways to avoid sensory overload. This can include modifying the environment, using earplugs or headphones, or developing a "sensory diet" to ensure the right level of stimulation.
In severe cases, antipsychotic or ADHD drugs may be used to minimize the triggers that contribute to meltdowns in people with autism.
A Word From Verywell
Understanding the sensory challenges of autism allows you to create a comfortable environment for your loved one and to respond appropriately if a meltdown occurs. In the end, the more that you educate yourself about autism, the more empathetic and compassionate you will be as a caregiver.
Doing so can also help you cope. By taking a practical approach rather than an emotional one, you'll be better equipped to avoid feelings of embarrassment or anger if and when a meltdown occurs.
How to Create a Sensory Room for Your Autistic Child
Frequently Asked Questions
What causes sensory overload in autism?
Sensory overload occurs when an intense or persistent sensation overwhelms a person's ability to cope.
With autism, the stimulus is often environmental, such as an offputting sound, smell, sight, taste, or texture. The stimuli can vary from one person to the next and even one situation to the next.
Can medications treat sensory overload in autism?
There are no medications that treat sensory overload. However, there are some that may help control the triggers that fuel sensory overload in people with autism.
These include atypical antipsychotics like Risperdal (risperidone) and ADHD medications like Ritalin (methylphenidate).
Can sensory overload be dangerous?
People with autism will often respond to sensory overload with repetitive behaviors known as stimming.
While most stimming behaviors (like hand-flapping or rocking) are harmless, others (like head-banging, scratching, or biting) may cause self-injury or harm others. Medications may be needed to control these extreme stimming behaviors.