Neurodiversity 4 of 7: Our sensory systems

To start understanding how neurodivergent brains work, we have to understand how our sensory systems work. All neurodivergents have highly sensitive nervous systems. We’ll get into what exactly that means in a moment, but these kinds of nervous systems have a much greater risk for physical and mental health challenges, and a much higher risk for these problems becoming chronic. Issues like chronic pain, muscle spasm, joint problems, anxiety, depression, eating disorders and digestive issues like Irritable Bowel Syndrome are common among highly sensitive people. These physical challenges also reduce mental health function, not just because they are painful and uncomfortable, but because of complex body-mind interactions like the gut-brain axis and other chemical factors. The feedback loop this creates – the mind creating body problems, the body problems perpetuating the mind problems – can keep people stuck in disease and ill health for many years.

I have also seen with my patients (and myself), that having a highly sensitive nervous system limits one’s access to healthcare, since most medical environments are overwhelming, often traumatizing, and treatments often make things worse. There is a huge need in the medical world for a wider understanding of what it feels like to have a sensitive nervous system, and how many conventional treatments are not just ineffective, but actively sabotage healing on a physical and mental level. It is part of my purpose to bring this awareness into the medical field, and help create new systems that are more effective and less damaging to these kinds of people. These systems will be more conducive to human health overall, no matter their neurotype.

The human population has huge natural variety in nervous system sensitivity levels, just like all other brain functions. [insert image somewhere close to this parapgraph: NS sensitivity]. The larger part of the population has low to medium sensitivity levels, while the highest end of the sensitivity spectrum is occupied by neurodivergents. There is another category in-between these two – officially called “Highly Sensitive People” or HSP, a term coined by psychologist Elaine Aron in her book “The Highly Sensitive Person: How to Thrive When the World Overwhelms You”, published in 1997 [3]. These people are more sensitive than most, but not quite as sensitive as neurodivergents. Many neurodivergents first discover there is something different about themselves when they realize they are highly sensitive. Not all HSP’s are neurodivergent, although they certainly may be.

Highly sensitive nervous systems

A person with a highly sensitive nervous system (HSP or neurodivergent) will have an increased capacity to sense, locate, describe and express the detail of all inner and outer sensations they experience. They usually also have a much higher ability to discern the differences between subtle details and changes in their sensation. This applies to all our senses, and we have so much more than our five senses.

Our bodies also have internal senses – those that help us identify what is going in inside our bodies at all times. Examples are proprioception (the awareness of position and movement), interoception (the awareness of our internal metabolic processes) and the vestibular sense (our sense of balance and spatial orientation). Emotions also fall loosely into this category, since we use our interoceptive senses to feel and identify our emotions via the physical reactions they produce within our bodies.

We also have social senses – those that help us function in society by communicating and interacting with people. As humans, we are all able to sense another person’s attention on us, even without seeing them looking at us. That’s why public speaking is so hard for many of us. We can also sense another person’s intention when they approach or speak to us – we know intuitively whether they mean us harm or not. Reading other people’s emotions via their body language and facial expression is essential for social interaction as well, but we also are able to sense others’ emotions within our own bodies, even without looking at them. If you are a highly sensitive person, you know what it’s like to feel someone else’s anger in your own body just because you are standing next to them. You know you can sense a tense ‘vibe’ in a room you enter just after someone had an outburst, even if nobody is speaking. We also have protective senses, for example neuroception, which is our capacity to sense danger or safety in our environment at any time. These senses are much more complex than our simple five senses of taste, touch, sight, hearing and smell. Most people don’t really pay these senses much attention, they just work. But when you are highly sensitive, your connection to all these senses determines how you function in the world, and they are often the reason you’ll struggle to spend time in social environments, and sometimes have a tendency to socially isolate and withdraw.

Practically, this feels like we absorb everything from our environment – the task we’re focusing on, the way our pants hug our skin, the way the fold in our sock irritates our foot, the gentle breeze of our own breath, the nervous tapping of our colleague sitting next to us, the distant beeping noise in the background, the way that light flashes in the window every time a car drives past, someone’s kid screaming one block over, the car alarm about five blocks away. And we notice everything going on inside us as well – the tension in our belly because that car alarm reminds us of danger, the slight tightness in our throat from the anxiety we woke up with this morning (probably because that action movie last night gave us weird dreams), the subtle headache starting in our temples, the way our inner ears are hurting from trying to numb out the sound and are failing, the way our eyes are drying up from staring at the computer too long, the way that sandwich at lunch sits like a stone inside our stomachs because we forgot to choose the gluten-free option, the way our breathing is still a little racy from the stress of that confrontation those two colleagues had in the other room a moment ago. Most people would go crazy if they were this aware of all these details at all times, and, believe me, often it is hard not to scream in frustration. But highly sensitive people were born like this, so we’ve had our entire lives to find ways to cope – mostly having to do with numbing ourselves or pushing through the discomfort and anxiety of our daily lives. 

It is easy to assume that highly sensitives have “better” sense organs, but this isn’t really what’s happening. Being highly sensitive means that our brains process sensory information differently, and it does not necessarily have much to do with our actual eyes or ears. When we are stressed or holding old trauma, that chronic dysregulation can affect how our cranial nerves control our actual eyes and ears, making everything worse, but this is the part that can be healed. The part that makes us highly sensitive that lives in our brain is a part of who we are.

Read the next article in the series: Neurodiversity 5 of 7: Sensory struggles in neurodivergents