The sensory system is how the body receives, processes, and responds to information from the environment and within the body.
It helps us understand what we see, hear, feel, smell, taste, and how we move
Sensory
"Sensations are food for the brain" Dr Jean Ayres
Olfactory (Smell)
“If a picture is worth a thousand words, a scent is worth a thousand pictures.” -Joel Bellenson
Our sense of smell is a complicated sense. First, we detect a smell which then sends a bundle of nerves to the olfactory bulb in our brain. It is here that the information is filtered and perceived to potentially help us make our next decision eg. burning toast tells us to get the toast our the toaster. The olfactory system is part of our limbic system (our emotional brain), this is critical in our behaviour, mood and long term memory. It explains why a certain smell can take us straight back to a very specific location or person, which can hold both positive or negative memories. We may feel sad before we have understood that a scent triggered it. This is important to remember when working with children who have experienced trauma.
Hyposensivity
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Not notice strong or unpleasant smells
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Seek out strong scents (e.g., smelling objects, people, or food)
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Have reduced awareness of personal hygiene (e.g., body odour)
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Prefer very strong-smelling foods
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Seem unaware of environmental odours
hypersensitivty
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be very sensitive to everyday smells (e.g., food, perfumes, cleaning products)
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Complain about smells others don’t notice
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Avoid certain places (e.g., toilets, dining areas) due to smell
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Feel nauseous or uncomfortable around strong scents
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Be selective with foods based on smell
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Become distracted or distressed by odours
Visual
Our sense of vision is how we see and understand what we are looking at. It involves not just the eyes, but also how the brain interprets visual information. We rely heavily on this sense everyday.
The visual sense is key in helping us learn and recognise letters, numbers and shapes. It also is required for reading and tracking across a page. It helps us judge space and is needed for hand-eye coordination. It also helps guide our motor movements and posture by working with other senses such as the tactile and proprioceptive system.
hypersensitivty
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be very sensitive to everyday smells (e.g., food, perfumes, cleaning products)
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Complain about smells others don’t notice
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Avoid certain places (e.g., toilets, dining areas) due to smell
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Feel nauseous or uncomfortable around strong scents
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Be selective with foods based on smell
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Become distracted or distressed by odours
Hyposensivity
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Not notice strong or unpleasant smells
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Seek out strong scents (e.g., smelling objects, people, or food)
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Have reduced awareness of personal hygiene (e.g., body odour)
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Prefer very strong-smelling foods
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Seem unaware of environmental odours
Tactile (Touch)
The tactile system is our interpretation and response to touch. Touch is one of the first sensory systems to evolve and helps us to feel safe and secure as babies. Our touch receptors begin to develop in our lips and nose first, which is why babies often bring toys and objects up to their mouth.
Our tactile sensory system is split into two sections: Discriminative and Protective
Discrimination helps us understand where we are touched (localisation) and the shape, size and weight of the object.
Protective section is critical to alerting us to danger. Such as when you touch a hot stove and pull your hand away as a protective reflex from the quick processing of temperature.
Hyposensivity
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Not notice when their hands or face are messy
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Seek out touch (e.g., touching everything, fidgeting)
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Use excessive pressure (e.g., pressing hard when writing)
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Have a very tight or very loose grip on tools
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Seem unaware of touch unless it is strong
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Enjoy messy play more than expected
hypersensitivty
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Avoid messy play (e.g., paint, glue, sand)
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Dislike getting hands dirty or wet
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Be bothered by certain clothing (labels, seams, fabrics)
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Pull away from touch or dislike unexpected contact
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Avoid activities like cutting, writing, or crafts
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Frequently wipe their hands or seek to keep them clean
Gustatory (Taste)
Our tongue can differentiate between these 5 flavours.
The sense of taste is how we detect and respond to different flavours through the mouth and tongue.
It helps us recognise tastes such as: Sweet, sour, salty, bitter and savoury.
A big part of this sense is for the enjoyment of food and making food preferences. However, it can also be helpful as a protective factor in stopping us swallowing dangerous foods such as spoiled foods. It works alongside the visual and olfactory system to ensure we put safe food in our mouth. The olfactory system also helps the gustatory system to identify the flavours.
Hypersensivity
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Very selective or “picky” eating
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Strong reactions to certain tastes (e.g., bitter, sour)
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Prefers bland or familiar foods
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Gags or refuses certain foods
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Avoids mixed textures or strong flavours
Hyposensivity
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Prefers strong, spicy, or highly flavoured foods
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May add lots of sauces or seasoning
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Puts large amounts of food in their mouth
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May not notice subtle flavours
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Can seek intense taste experiences
Messy Chef
Messy Chef is an intervention used by Occupational Therapists and Speech and Language Therapists to support children who are 'fussy eaters' or selective eaters.
A YouTube video on this evidence based programme can be found here.
Furthermore, the programme was presented at the OT show 2022. Please see here for more information.
Auditory
The auditory sensory system detects, interprets, and responds to sound waves via the ear and brain. Around 5% of children are diagnosed with Auditory Processing Disorder (APD), whereby the child's hearing is working, but the messages are not being processed and interpreted correctly.
Sound waves travel through the ear into the eardrum, here the vibrations hits small bones which amplifies the sound. The inner ear (cochlea) converts the sound into an eletrical signal which passes through the auditory nerve into the brain where it is processed.
Hypersensivity
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Covers ears in response to noise
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Distressed by loud or unexpected sounds (e.g., hand dryers, bells)
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Distracted by background noise (e.g., chatter, humming)
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Avoids noisy environments
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Becomes anxious or overwhelmed in busy settings
Hyposensivity
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Does not respond when name is called
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Appears not to notice sounds others do
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Seeks noise (e.g., making sounds, turning volume up)
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Enjoys loud environments
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May have difficulty following verbal instructions
Proprioception
Proprioception is the body’s ability to sense where it is in space and how it is moving, without needing to look. It comes from information in the muscles and joints. It is important in helping us grade force, so we know how much pressure to push down on a pencil without it snapping, or how hard to throw a ball towards a target.
It is important to know that proprioceptive input is the most regulating sense for most people. It allows our bodies to organise itself with reliable information about the body which helps us to feel grounded, connected and safe.
Hypersensivity
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Avoids rough play or physical activities
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Dislikes too much pressure (e.g., tight grips, heavy work)
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May appear cautious or hesitant with movement
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Tires easily during physical tasks
Hyposensivity
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Seeks movement and “heavy work” (pushing, pulling, crashing)
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Uses too much or too little force (e.g., presses too hard when writing)
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Appears clumsy or bumps into things
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Enjoys tight hugs or deep pressure
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Fidgets or struggles to sit still
Vestibular
The vestibular system is our sense of balance and movement. It is located in the inner ear and helps to detect movement, gravity and head position. It helps tell us whether we are moving, how fast we are moving, which direction we are moving and how our head is positioned in response to gravity (such as upright, tilted or upside down). It is key in postural control (how we maintain balance and stability), by coordinating muscles, detecting head position, integrating proprioception and vision and adjusting automatically to changes.
The inner ear contains a structure called semicircular canals which are filled with a fluid (endolymph) and sensory receptors. When the head moves, endolymph in the canals also move which bend sensory hair cells. The movement of these hair cells sends a signal to the brain about linear movement, rotational movement and changes to the head position. The brain then uses this information to adjust posture, balance, and eye movements.
Hypersensivity
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Avoids playground equipment (swings, slides, climbing frames)
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Becomes dizzy, nauseous, or fearful during movement
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Dislikes being lifted, tipped, or spun
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Moves cautiously or slowly
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Becomes anxious in busy or fast-moving environments
Hyposensivity
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Hyperactive and impulsive. Appears constantly energetic, fidgety, or unable to sit still.
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Motion seeking behaviours
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appears uncoordinated or have poor balance.
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Need for Stimulation: May rock back and forth.
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High Tolerance for Spinning: Can spin without getting dizzy.
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May engage in Risk-Taking Behavior such as Lacking fear of heights
Interoception
The interoception sensory system is a powerful hidden internal sense that helps us perceive and interpret bodily signals. It tells us internal sensations such as hunger, pain, thirst, needing the toilet or temperature to name a few.
This sense is responsible for helping us to understand what is happening on the inside in order to survive, be comfortable and feel regulated. It keeps us well-balanced.
Interoception plays a key role in emotional regulation, with the body giving cues that inform our feelings. For example, a rumbling tummy tells us we are feeling hungry which may make some people feel angry aka hangry! Some children may feel silly when they need the toilet as the internal feeling is confusing. It can be easily used alongside the Zones of Regulation.
The Interoception Curriculum is a powerful programme that is used in my place of work to help children not only understand their internal cues and how this connects to their emotions, but to also know how to build a toolbox to support these sensations and related emotions.
Kelly Mahler is the queen on interoception and has a website with an abundance of information.
Click here for more information. Kelly Mahler also has free courses and training videos which are very informative.
I have created visuals that are useful in helping children communicate their internal needs.
Hypersensivity
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Strong reactions to pain or discomfort
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Easily overwhelmed by internal sensations (e.g., hunger, needing the toilet)
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Increased anxiety linked to bodily feelings (e.g., heart racing)
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Difficulty managing emotions due to intense internal cues
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May frequently report feeling unwell
Hyposensivity
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Does not notice hunger or thirst
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Difficulty recognising the need to use the toilet
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Reduced awareness of pain or illness
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Finds it hard to identify or describe emotions
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May appear unaware of their body’s needs