Sensory processing is the way our nervous system receives messages from our senses, turning them into motor or behavioural responses. The ability to receive and process sensory information from our environment can impact attachment, speech and language, motor coordination and our day-to-day living skills.
Main sensory systems
Sensory information includes the five senses:
- visual (sight),
- auditory (hearing),
- tactile (touch),
- olfactory (smell)
- gustatory (taste).
There are also three further senses:
- vestibular (balance)
- proprioceptive (body awareness)
- interoceptive (bodily needs such as hunger or body temperature)
What types of difficulties can people have with these systems and how do they affect everyday life?
Sensory processing disorder (SPD) can mean you are overly sensitive to particular senses or conversely, need more stimuli from senses.
Examples of behaviour / experiences relating to being overly sensitive to sensory stimuli might include:
- Visual: Experiencing overhead/ fluorescent/ lighting as too bright
- Auditory: finding “normal” classroom chatter too loud
- Tactile: getting irritated by clothing labels
- Olfactory: feeling nauseous from some food smells
- Gustatory: needing food puréed for digestion
- Vestibular: having difficulty controlling movements in sport
- Proprioception: finding it hard to tie shoelaces
- Interoception: overeating to avoid hunger pangs
Examples of behaviour / experiences relating to being under-sensitive to sensory stimuli or being ‘sensory-seeking’ might include:
- Visual: seeking visual stimulation through computer games
- Auditory: enjoying banging doors/making loud sounds
- Tactile: being drawn to touching other people or stroking self
- Olfactory: not acknowledging own body odour
- Gustatory: eating rocks, earth, grass,metal (known as pica)
- Vestibular: enjoying rocking, swinging
- Proprioception: bumping into people
- Interoception: having toileting accidents
These sensory processing difficulties can have a huge impact on everyday activities in school, work or out in the community. For example, children in school who are overly sensitive may feel overwhelmed by classroom lighting or even low background noise. This could lead to feeling overwhelmed and unable to carry out smaller tasks.Children who seek sensory stimulation, may make loud noises during a quiet exam or stroke others’ hair (stimming). This could be disruptive to others and children may learn to suppress this, leading to sensory dysregulation.
Sensory processing is not simply binary though,as Dr Temple Grandin explains,
“One of the problems in understanding sensory issues is that sensory sensitivities are very variable, among individuals and within the same individual. A person can be hyper-sensitive to one area (like hearing) and hypo-sensitive in another (like touch)”1
What developmental conditions / mental health problems are SPD linked to?
Children and adults with sensory processing difficulties often have comorbid conditions such as poor motor skills, anxiety or depression. In some cases, there is a link to autism and developmental trauma.
With autism, nerve cells can be over or under connected, leaving message processing flooded by nerve cells firing or under-stimulated respectively.
Messages can even be sent to the wrong processing area, leading to synaesthesia: the sound is heard but processed as a particular colour.
Some children experience gestational abuse or neglect: for example, perinatal drug or alcohol abuse (foetal alcohol syndrome.) Other children are neglected or abused as young children, leading to hypervigilance, with accompanying fight, flight, freeze or fawn stress responses. This adversely harms capacities to filter out overwhelming sensory input, such as background noise- a result of desensitisation to the possibility of danger.
Regulating sensory arousal becomes haphazard, some children may seek their caregivers’ attention through sensory soothing or through avoidance, if historically sensory needs hadn’t been met.
What can help: Sensory integration therapy
The Ayres’ sensory integration intervention assessment and therapy looks at sensory processing difficulties and suggests strategies to help. The Occupational Therapist will often use a sensory room for therapy sessions, equipped with a ball pit, weighted blankets and fidget toys to support sensory defensiveness and/or cravings.
These strategies can then be used independently by the child, or supported through families and schools.
Occupational therapists will suggest beginning the day with a bespoke sensory circuit: activities to energise or soothe the senses. This can help children prepare for learning at school. These can include:
- energising activities such as star jumps or skipping
- coordinated activities such as juggling or a wobble board
- heavy muscle activities such as using weights
A further sensory diet throughout the day and evening includes activities to help sustain attention, focus and regulation. These can include:
- stimulating low arousal through dancing or singing
- lowering arousal through listening to music or walking.
These strategies at home and school can help sustain daily regulation throughout the demands of the day, helping prevent sensory overload and decrease anxiety.
Insight from Temple Grandin
Dr Temple Grandin is Assistant Professor of Animal Science at Colorado State University, specialising in designing livestock equipment and renowned speaker and author on autism. She gives worldwide talks about her experiences of autism and sensory processing.
Temple wrote an extraordinary autobiography: ‘Emergence’ in 1968, which gave a compelling insight into her sensory processing as a child. She describes her infant hearing like microphones broadcasting at full, undulated volumes. She remembers violent rages, often originating from unmodulated sensory processing. Whenever she was hugged by her mother or visiting aunts, she felt like a trapped animal, leaving her desperately wanting to claw her way out. She used her own faeces rather than clay for modelling, spreading it around rooms.
Eventually, she learn how to innately temper her regulatory system, through retreating into her own little world through immersive sand activities:
- Sitting on the beach, enjoying the feeling of sand running through her fingertips and building sand castles.
- Imagining each grain of sand under a scientific microscope
- Trailing lines of sand on each finger, imagining each one a road map
- Intense concentration allowed total bodily and mind immersion – oblivious to the hive of people and noise around her.
Where sensory difficulties are suspected, it is important to have an accurate, thorough sensory assessment, and access to therapeutic help.
The Purple House Clinic, Leicester, offers comprehensive sensory assessments and sensory integration therapy with an Occupational Therapist and Sensory Integration practitioner. The assessments take place in a fully equipped sensory room, with ball pit, play den, range of tactile objects and books.
Sensory screening is also available at our Rugby and Lincoln clinics, as part of the autism and trauma care pathways. As part of the trauma care pathway, children accessing therapy at The Purple House Clinic, Lincoln, have access to a sensory room, complete with sensory tent and bubble tube to help with sensory regulation. The Rugby Clinic can also offer full, sensory assessments through an Occupational Therapist.
The Glasgow clinic can offer comprehensive sensory assessments with an Occupational Therapist through home-visits, to help children feel more comfortable.
1 Temple Grandin, “The way I see it: a personal look at autism and asperger’s”: 32 (2008)