Understanding sensory processing or integration

Sensory processing differences describe the experiences children (and adults) have when their brains interpret the sensory messages received from their body and the environment differently to others.  They may interpret the sensory messages more or less intensely or they may not notice them at all! Sensory differences can also affect movement and coordination skills.  You will also hear the terms ‘sensory integration dysfunction’ and ‘sensory processing disorder’ being used to describe them.  In this article I will explore

  • A definition of sensory processing differences

  • Why I refrain from using sensory processing disorder

  • What sensory differences might feel like

  • The different areas of sensory processing

boy with coloured paint on hands text what is sensory processing disorder

Understanding sensory processing or integration

Sensory processing differences describe the experiences children (and adults) have when their brains interpret the sensory messages received from their body and the environment differently to others.  They may interpret the sensory messages more or less intensely or they may not notice them at all! Sensory differences can also affect movement and coordination skills.  You will also hear the terms ‘sensory integration dysfunction’ and ‘sensory processing disorder’ being used to describe them.  In this article I will explore

  • A definition of sensory processing differences

  • Why I refrain from using sensory processing disorder

  • What sensory differences might feel like

  • The different areas of sensory processing

Interpreting Sensory Messages

As I said above, sensory processing differences (or sensory processing disorder) describe the experience of children and adults who’s brains interpret sensory messages differently to others.  This difference can occur with any with any of the eight senses.  Because the brain is interpreting sensory messages differently,  responses to sensory information may not be what is expected by others (Bialer & Miller 2011).  It may also result in poor coordination or dyspraxia.

The terms Sensory Processing Disorder or Sensory Integration Dysfunction may be used by occupational therapists and other professionals to describe these differences. Whilst the term sensory processing disorder is used frequently, we need to be mindful that to date, it has not been included in the diagnostic manuals as a standalone diagnosis. That is not to say that it won’t be in the future, but as of writing this update (August 2024) it is not.  This is why I am very mindful when I use the term, and prefer to use sensory processing differences.  I appreciate that some people find the term sensory processing disorder more helpful as a description as it is widely know.

Autistic children and adults frequently experience sensory processing differences and in 2013, hyper or hypo-reactivity to sensory input was included in the updated diagnostic criteria for autism. On this page, I will describe what sensory information is and the different sensory issues that may present for children and adults with sensory processing challenges.  There is more information on sensory processing and autism here.

What is sensory information?

Sensory information is any message that our bodies receive from our eight senses.  This information may come from the environment, or from inside our own bodies.  For example, when we chew something crunchy we hear the crunch sound in our mouth.  The brain receives sensory information from the five senses that most of us are familiar with, taste, smell, sight, hearing, and touch.  It addition, it receives information from our proprioceptive, vestibular and interoceptive senses.

Learn more!

If you want to explore the senses in further depth – you can join my free introduction to sensory processing here.

girl in beanbag with teacher rolling textured ball text touch sense

Olivia’s story – sensory slow

Olivia doesn’t always notice what’s happening in the room.  Often, she doesn’t respond to her name.  Sometimes it seems like she is oblivious to the world around her.  Her movements are slower and a bit clumsy.  She needs encouragement to have a go and to try activities that her friends just automatically start.  Overall, her responses to the sensory messages she receives from the world are slower when compared to others.

What happens when there are sensory processing issues?

The senses of children and adults with sensory needs still receive sensory messages, this means there are usually no problems with their vision or hearing or touch sense.  However, their brain processes the sensory information differently to those who do not experience sensory differences.  It is thought that their brain does not integrate, or process, sensory information in the same way as others.

This means that their responses to sensory information might not always be what is expected by others. It may also mean they find some environments or activities more challenging.  This is because a child or adult might find certain sensory information too intense and be overwhelmed.  Or, they need might need stronger messages from their senses, and seek out more sensory input.  Some children might not even notice the sensory events happening around them.

I explore these responses in more depth on this page signs and symptoms of sensory processing differences.  Here, I list some of the common behaviours seen if someone has poor sensory integration or sensory needs. It can be quite confusing to pick out these differences, and I cover them in more depth in my sensory training, you can join the training here.

Don’t judge other’s response to sensations from your own perspective!

It is very important for you to remember is that for children and adults who report sensory issues is that the experiences are very real for them.  They are not right or wrong, correct or incorrect. It just just how their own brain interprets sensory messages.  This can be very different to how others interpret the same sensory information. Even if it occurs at the same time and place.  When supporting children or adults with sensory processing disorders you must remember this.  Their responses are neurologically triggered and sometimes out of the person’s control, for example, running off if there is a loud noise without considering safety.

This video describes sensory processing difficulties from a child’s perspective:

What are the different areas of sensory differences?

There are two main models describing sensory processing differences within occupational therapy. Lucy Miller (2014) identified three parts when she described Sensory Processing Disorder (SPD), modulation, discrimination and movement.  The model presented by Bundy & Lane (2019) separates sensory integration differences into two areas sensory modulation and movement. The image below aims to group this information.

Sensory Processing Disorder/Differences - modulation (sensitive/slow), discrimination (all senses), movement (dyspraxia, posture)

SPD – Sensory modulation

The first component is sensory modulation.  Sensory modulation is the ability to produce a behaviour and/or response that matches the nature and intensity of the sensory input and environment (Lucy Miller 2014 p.14).  This means that the child or adult’s response to the sensory messages is what would be expected; the response would match what had occurred.  The responses of children and adults with sensory differences often do not match the sensory message or environment. There can be challenges with some or all senses.  Sensory issues related to modulation difficulties can include:

  • Over-responsivity, or sensitivity to sensory input;
  • Under-responsivity or slower responses to sensory input;

I discuss these responses in more depth on this page: signs and symptoms of sensory issues.

Sensory modulation is also  called sensory reactivity by some therapists.  These therapists will consider hypo and hyper reactivity.  So, a slower (hypo) reaction.  Or, a bigger (hyper) reaction.  Reactivity is being used to bring terminology inline with the 2013 update of the autism diagnostic criteria in a book called the DSM-V.

What about sensory seeking?

Sensory seeking has always been perceived as a behavioural response to sensory modulation differences. It was initially perceived to be a response to a slower responses, i.e., the child or adult needed more input to understand the sense and sought this out.  However, we know it is more complicated than that. For example, sometimes children or adults seek information from one sense to help to decrease the impact of or drown out another sense they may be sensitive to. This is why it is no included as a response type in the models, as it is a behavioural response, rather than a reaction to the sensation. I know it’s confusing and this is why my online training covers this in a lot more detail.

SPD – Sensory discrimination

The second component of SPD is discrimination.  Sensory discrimination is knowing what the sensory input was, where it happened and how intense it was.  So, if you stub your toe your brain should be able to figure out (or discriminate) which toe it was and how hard you banged it.  When you put your hand into your bag to find your keys, your touch sense can identify (or discriminate) the feeling of your phone and wallet from your keys.  When you open a pot of yogurt your proprioceptive system pulls the lid with enough force to open it but hopefully not spill it everywhere!  These are examples of discrimination.

Some therapists will use the term sensory perception when they are talking about sensory discrimination.

SPD – Sensory-based movement

The third component of SPD is sensory-based movement.  In this section, Miller (2041) includes praxis and posture.  Praxis is the ability to plan and organise new and novel movements. It is exceptionally important for learning new skills.  People are often more familiar with the term dyspraxia which means difficulty with praxis or planning.  Posture relates to postural control, balance and stability.

You can read more about how these sensory processing challenges could look for different children on our signs and symptoms of sensory issues page.  If you wanted to learn more about dyspraxia you can read our post – Dyspraxia it’s more than clumsiness.