The eighth sense? But I thought there were only five senses?
We teach kids in elementary school about the five senses–taste, touch, small, hearing, and sight–but there are actually more. The other three are just a bit harder to explain to a group of five year olds so most people don’t know about them.
The other three “official” senses are 1) the sense of head movement in space, which utilizes the vestibular system, 2) the sense of muscle and joint movement, which utilizes the proprioceptive system, and 3) the awareness of internal body functioning, which is known as interoception. And if I could make an educated guess on the matter, I’d say there are more than this that haven’t been officially coined, yet. The first unnamed “senses” that come to mind are the sense of danger–think of the hairs on the back of your neck rising up–and the sensation of physical pain on the outside of your body.
In a few years, we’ll probably be learning about the ten senses! Or the twelve senses! It’s really amazing how science evolves and then we’re suddenly learning about phenomenon we never knew existed.
The eighth sense, which we’ll be discussing today, is interoception. This is our sense of something being not right within our bodies. For example, if we have a properly developed sense of interoception, we get a stomachache when there’s something upsetting our digestive tract. We feel nausea when our body is close to vomiting. We feel pain in our appendix before it bursts. We feel our heart racing after having too much caffeine. We feel a headache when we’ve strained our brains too long during the day.
Any time we feel something amiss inside one of our internal organs, our sense of interoception is working.
Unfortunately, there are a lot of kids who either have underdeveloped senses of interoception or heightened versions of it. It’s similar to how someone can have no sense of smell whatsoever, or they can have such a heightened sense of smell that they’re extremely sensitive to becoming queasy over powerful scents. The sense of interoception is the same.
Most kids who have Sensory Processing Disorder–which often co-occurs alongside ADHD, Autism, and Anxiety–have dysregulated senses of interoception. Sometimes, they feel the sensation of having a stomachache, but the message sort of gets lost from their belly to their brain, and they don’t really understand that it’s a stomachache. This can manifest in behavioral meltdowns because, on some level, their body knows something is wrong, but their brain can’t identify and their mouths can’t explain it.
They also tend to struggle with knowing when they’re going to throw up. My nephew has Sensory Processing Disorder, and he generally throws up without any warning whatsoever because he doesn’t alert anyone that he’s feeling nauseous. We used to wonder why he didn’t act any different or tell us before vomiting, but then we realized he doesn’t feel the nausea. He has no idea it’s coming. Once, he threw up in the middle of sleeping on his back and didn’t even wake up from it. Another time, he vomited mid-sentence and just looked confused afterward.
And he’s a kid that “seems” typical on the outside so people are often confused when he has a meltdown for no reason. There is usually a reason. He just doesn’t know what it is, and, therefore, cannot explain it to others.
Most kids with SPD experience these muted sensations in the area of interoception, but then experience heightened senses of smell or touch. They can’t feel vomit about to leave their throat, but they can feel the bump inside their sock and it physically HURTS them. They might have no idea they’re about to poop their pants, but they can literally FEEL the lights and sounds inside a grocery store.
These disproportionate senses can cause behavioral episodes that are hard for others to understand.
Newer studies have started conducting “heartbeat tests” to identify people who have heightened senses of interoception. These studies have found that those with heightened senses of internal feelings, a person is also more likely to experience extreme emotions. They feel happiness more intensely than others, but they also feel anger, sadness, and shame more intensely.
Kids with SPD are more likely to experience these intensified emotions, yet are less likely to be able to communicate them in socially acceptable ways.
Do you have a child with Sensory Processing Disorder who is affected by an altered sense of interoception? Were you once a child who experienced these things but didn’t know why?
Tell us your story!