Sensory Overload: Symptoms, Causes, and Treatments

Sensory overload occurs when one or more of the body's senses is overstimulated to a point where a person is unable to cope. It happens when your brain gets more information from your senses than it can process. People who are experiencing sensory overload may feel irritable, anxious, or emotional. Often, sensory overload causes distress.

Sensory overload is a term commonly associated with autism but can also be applied to other disorders like post-traumatic stress disorder (PTSD) and obsessive-compulsive disorder (OCD).

This article explores the traits associated with sensory overload and its causes. It also covers what can be done to ensure the right level of stimulation for someone who experiences sensory overload.

Traits Associated With SPD

Sensory overload is a type of sensory processing disorder (SPD). SPDs are conditions in which a person is either over-responsive (sensory hypersensitivity) or under-responsive (sensory hyposensitivity) to environmental stimuli.

In some cases, the hypersensitivity may be so intense 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 lead to certain traits, including:

• Anxiety and fear
• Restlessness
• Irritability or anger
• Overexcitement
• Muscle tension
• Increased heart rate
• Rapid breathing
• Profuse sweating
• Covering the ears or eyes to block out the stimulus
• Not wanting to be touched or approached
  

In some cases, sensory overload can cause self-harming behavior like head banging, ear-clapping, self-scratching, or self-hitting.

Other Possible Responses

People who witness a sensory overload 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 who experiences sensory overload 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.

Possible reactions an autistic child may have include:

• Stimming: Repetitive behaviors such as rocking, pacing, or foot tapping
• Sensory-seeking behaviors: 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
  

What Causes Sensory Overload?

The causes of SPDs are poorly understood and can differ based on a diagnosis of autism, ADHD, PTSD, or other developmental or psychiatric disorders.

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 may also overreact to three additional senses that impact balance, motor skills, and body awareness.

The additional senses are referred to as:

• Vestibular: This refers to structures in the inner ear that detect 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. This can lead to balance and coordination problems in addition to the more common traits of sensory overload.

Related Conditions

Sensory overload is most common in autistic children and attention deficit hyperactivity disorder (ADHD). It can also affect autistic adults, including those with low support needs.

Autism

People diagnosed with an autism spectrum disorder (ASD) 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.

They also have challenges in understanding social cues and may 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 autistic children experience SPDs.

Unlike neurotypical people (people without autism), autistic people 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 autistic people better cope with stress and sensory overload.

ADHD

People with ADHD have difficulty processing sensory information. This makes them especially sensitive to external stimuli like bright lights, loud sounds, and strong odors. They may also be bothered by certain physical sensations, such as the feeling of a particular fabric.

ADHD is associated with difficulty regulating emotions, trouble with change, and a lack of awareness of physical surroundings. All of these things can contribute to sensory overload.

Anxiety

People with anxiety disorder commonly experience sensory overload. Anxiety causes a stress response in the body, which can trigger a fight-or-flight reaction. When this happens, a person becomes more sensitive to external stimuli.  

Sensory overload can happen alongside other anxiety symptoms or independently. Sensory overload can also trigger feelings of anxiety.

Fibromyalgia

Sensory overload is common in people with fibromyalgia. The root cause of fibromyalgia isn't well understood, but it's believed to be related to hypersensitivity to external stimuli.

People with fibromyalgia experience pain sensations more strongly than people who do not have the condition. They can also be hypersensitive to other types of stimuli such as noise and heat. 

Multiple Sclerosis

People with multiple sclerosis (MS) may experience confusion, fatigue, or even pain in the presence of stimuli such as noise or chaotic environments. 

MS also causes myoclonus, or involuntary muscle twitching. This symptom can be triggered by overwhelming external stimuli.

PTSD

Post-traumatic stress disorder (PTSD) develops after a traumatic event. It causes intense anxiety, stress, and oversensitivity to surroundings.

People with this condition are typically hypervigilant, which means they're over-aware of what is happening around them. This can cause sensory overload in the presence of loud sounds, flashing lights, crowded rooms, or other sensory-rich situations.

When the sensory stimuli are similar to those experienced during the traumatic event that triggered the condition, it can cause an intense emotional response. 

Sensory Overload in Children

Small children often have difficulty processing sensory information, especially when they are tired or overwhelmed. This is normal when it happens occasionally, especially in toddlers.

Sometimes, however, it becomes clear that a child has an outsized reaction to sensory stimuli. The child may be unusually sensitive to things like bright light, water, loud noises, and irritating sensations such as certain fabrics. These kids may also seem clumsy and have a low or high pain threshold.

Coping With 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 who experiences sensory overload.

Adults

People who experience sensory overload can learn to anticipate and cope with triggers. If you experience sensory overload, try the following strategies:

• Remove yourself from situations where known triggers are present.
• When you enter an unfamiliar place, look for "safe spaces" such as less crowded rooms or a quiet outdoor patio area.
• Arrange to meet people in low-key locations or at times when it is likely to be less crowded.
• Don't be afraid to excuse yourself early if you become overwhelmed.
• Don't expose yourself to situations that might become triggering if you are tired, hungry, or irritable.

Children

As a parent, guardian, or caregiver, it is important to recognize traits associated with sensory overload. That way, you can act swiftly or appropriately when it occurs.

• Be watchful of the signs of distress before your loved one has a meltdown.
• Encourage your loved one to communicate what is causing frustration, anger, or agitation so that you can remove the trigger, when possible.
• Ask 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.
• Make 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.
• Teach older children meditation or other self-calming techniques, such as deep breathing exercises, yoga, or guided imagery.
• Make an appointment with an occupational therapist so your child can gradually learn how to process sensory stimuli.
• If your child has sensory meltdowns and you are concerned about their well-being, talk to your pediatrician about medications such as Risperdal (risperidone) or Abilify (aripiprazole) for autism, or Ritalin (methylphenidate) for ADHD.
  

When to See a Healthcare Provider

Sensory overload can cause considerable stress to people who experience it 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 disruption, or any risk of self-harm or harm to others.

Speak with your loved one's healthcare provider to understand the benefits and risks of treatment so you can make an informed choice as a parent or guardian.

Summary

It is not uncommon for autistic people (and those with other conditions such as ADHD and PTSD) to be abnormally sensitive to certain sights, sounds, tastes, or textures.

Coping skills include avoiding triggers and recognizing the signs of overload before it occurs. Occupational therapists can help you find ways to avoid sensory overload.

Medication may be used to minimize the triggers that contribute to meltdowns in people who experience intense sensory overload.