Sensory overload occurs when one or more of the body's senses experiences over-stimulation from the environment.

There are many environmental elements that affect an individual. Examples of these elements are urbanization, crowding, noise, mass media, and technology.

Signs and symptoms

There are a wide variety of symptoms that have been found to be associated with sensory overload. These symptoms can occur in both children and adults. Some of these symptoms are:

  • Irritability
  • "Shutting down," or refusing to participate in activities and interact with others
  • Over-sensitivity to touch, movement, sights, or sounds
  • Avoiding touching or being touched
  • Irritation caused by shoes, socks, tags, or different textures
  • Complaining about noises that do not affect others
  • Covering eyes around bright lights
  • Covering ears to close out sounds or voices
  • Excitability
  • Making poor eye contact
  • Constantly changing activities without completing any tasks
  • Having trouble with social interactions
  • Extremely high or extremely low activity levels
  • Muscle tension
  • Hyperhidrosis (extreme sweating)
  • Fidgeting and restlessness
  • Angry outbursts
  • Self-harm
  • Insomnia
  • Fatigue
  • Difficulty concentrating

Causes

Sensory overload can result from the overstimulation of any of the senses.

  • Hearing: loud noise, or sound from multiple sources, such as several people talking at once.
  • Sight: crowded or cluttered spaces, bright lights, strobing lights, or environments with much movement such as crowds or frequent scene changes on television.
  • Smell and taste: strong aromas or spicy foods.
  • Touch: tactile sensations such as being touched by another person or the feel of cloth on skin.
  • Vestibular: such as dizziness or motion sickness.

As a component of other disorders and conditions

Sensory overload has been found to be associated with other disorders and conditions such as:

  • Attention deficit hyperactivity disorder (ADHD)
  • People with ADHD display hypersensitivity to sensory stimuli from a young age; this hypersensitivity often persists into adulthood. People with ADHD do not seem to differ in sensory processing in regard to most event-related potentials; however, they do display significant differences in event related potential responses involved with late cognitive processing such as P300, CNV, and Pe, which may indicate that hypersensitivity in ADHD is caused by abnormalities in the expectation of and allocation of attention to sensory stimuli. Irregularities in the production of and response to neurotransmitters is one possible etiology for sensory overload in people with PTSD; specifically, people with PTSD may display hypersensitivity to stimuli due to chronic homeostatic imbalances in dopamine and norepinephrine.
  • People with OCD display a cognitive inflexibility to changing environments. It seems that people with OCD are hypersensitive to stimuli that are indicative of negative situations, and this hypersensitivity may contribute to sensory overload. It is theorized that people with OCD have compulsions to carry out repetitive actions due to self-doubt and a desire to achieve perfection. A common trigger for compulsions in people with OCD is the perception of contamination; people with OCD commonly deal with the perception of contamination with repetitive hand washing.
  • People with schizophrenia are prone to sensory overload since people with the condition cannot divert their attention from repetitive and unimportant sensory stimuli. The inability to focus on relevant stimuli and filter out unnecessary and excessive sensory stimuli displayed in schizophrenics is due to physiological sensory gating issues, and the paired click P50 test can be used to determine if an individual has abnormalities in sensory gating and is therefore prone to sensory overload. A proposed theory that explains sensory overload in schizophrenic patients is that abnormalities in alpha-7 When people with misophonia are subjected to noises that trigger misophonic responses, they feel as if they are being overloaded by auditory stimuli and seek to escape from or block out the triggering noise. People with grapheme-color synesthesia report feeling visual stress and discomfort in response to gratings of mid and high spatial frequencies, People with GAD are biased to perceive sensory stimuli as negative or threatening and this bias feeds into negative thought processes which further exacerbate feelings of worry, stress, and anxiety.
  • Autistic people experience auditory hypersensitivity, which can lead to sensory overload. Although autistic people do not have abnormalities in P50 sensory gating, they have anomalies in sensory gating related to the N100 test which indicates an irregularity in attention-related direction and top-down mental pathways. A significant proportion of autistic people also have epilepsy, which can intensify the brain's sensitivity and potentially exacerbate sensory overload experiences.
  • Tourette syndrome
  • It has been suggested that people with Tourette syndrome have a hypersensitivity to bodily sensation that originates in higher order processing partially the result of distorted and higher than average amplitude of afferent somatic signals. People with Tourette syndrome sense urges to do tics that are often localized to regions of the body that carry out the tic response. Additionally, people with Tourette syndrome display a moderate inability to inhibit distracting stimuli which might lead to sensory overload. People with Tourette syndrome may be prone to carry out tics in an environment of overwhelming sensory stimuli.
  • Fibromyalgia
  • People with fibromyalgia are hypersensitive to intense stimuli such as bright lights, loud noises, perfumes, and cold temperatures; people with the condition also have hyper-excitable nociceptors. When people with fibromyalgia are subjected to intense stimuli, they experience sensory overload in the form of pain. It is theorized that abnormal activity of the left dorsolateral prefrontal cortex and reduced production of or reception to serotonin are partially responsible for the sensation of pain in response to intense stimuli. These sensitivities are partially explained by abnormal neurotransmitter pathways involving serotonin and acetylcholine. Most often the quickest way to ease sensory overload symptoms is to remove oneself from the situation. Deep pressure against the skin combined with proprioceptive input that stimulates the receptors in the joints and ligaments often calms the nervous system. Reducing sensory input such as eliminating distressing sounds and lowering the lights can help. Calming, focusing on music works for some. If a quick break does not relieve the problem, an extended rest is advised. People with sensory processing issues may benefit from a sensory diet of activities and accommodations designed to prevent sensory overload and retrain the brain to process sensory input more typically. It is important in situations of sensory overload to calm oneself and return to a normal level. Sensory overload is common among consumers as many corporations compete with each other especially when advertising. Advertisers use attention-grabbing colours, words, sounds, textures, designs and much more. This can influence the consumer, as they will be drawn to a product that is more attention grabbing. Simmel's approach can be compared to Freud's writings on shell shock as well as Walter Benjamin's analysis of "shock" and urban life in his 1939 essay "On Some Motifs in Baudelaire."

Case histories

Not many studies have been done on sensory overload, but one example of a sensory overload study was reported by Lipowski (1975) as part of his research review on the topic that discussed the work done by Japanese researchers at Tohoku University. The Tohoku researchers exposed their subjects to intense visual and auditory stimuli presented randomly in a condition of confinement ranging in duration from three to five hours. Subjects showed heightened and sustained arousal as well as mood changes such as aggression, anxiety, and sadness. These results have helped open the door to further research on sensory overload.

See also

  • Sensory adaptation
  • Sensory deprivation
  • Sensory substitution
  • Catatonia
  • Sensory processing sensitivity

References