A 12-year-old comes in for handwriting help, and within minutes the real story is sitting underneath him: a postural system that cannot hold him upright long enough to write. This episode follows that thread all the way down, from a messy three-minute writing sample to the vestibular processing driving it, and shows why the fix is never just more handwriting practice.
This is our first case episode, and Cory brings a composite of a 12-year-old boy referred for handwriting: poor legibility, ideas that will not make it onto the page, and a request from school for support. The assessment tells a bigger story. He shifts his whole body to cross the midline, props his head on his arm, fatigues within minutes, and his writing falls apart as he tires. We use Tracy’s sensory postural model, shared as a visual in the notes, to organise what we are seeing.
From there we go underneath the output to the inputs. We work through his clinical observations, the poor prone extension and supine flexion, the jumpy ocular tracking at midline, and the tonic labyrinthine reflex test that tipped him into autonomic overwhelm, and what they reveal about vestibular processing and postural adaptation. Tracy walks us through centre of gravity, why the eyes recruit help when the vestibular system cannot find stability, and how treatment starts: fast linear vestibular input, prone extension, and sound woven in, always building toward integration rather than chasing the handwriting itself.
Lightly edited for readability. Speaker labels and chapter markers match the published episode.
Cory: Hello, welcome. It is episode two. Hi Tracy, how are you?
Tracy: I am great. How are you guys down there?
Michelle: I am ready to go.
Cory: Ready to go. I am too.
Cory: So today I have brought a composite case that I think will be really helpful for everybody, particularly because at the end of our last episode we were alluding to postural functions. I assessed this little kiddo not that long ago and I thought, you are perfect. He is a 12-year-old boy who came into the clinic to be assessed mostly for handwriting challenges: real difficulty with legibility, not able to get his ideas out onto paper. The family wanted supports for school and to know how they could help him show his best academic potential. In the clinic I did the three Beerys, so the VMI, the visual perceptual test and the motor coordination test. I also did the Print Tool, from Handwriting Without Tears, and the handwriting speed test. And because I think it is so helpful to know about the postural system when you are assessing handwriting, I did the COMPS, the Clinical Observations of Motor and Postural Skills, with a few extras added in that are not formally on that assessment but that I find really helpful. Tracy, I have been to your lectures and you have great postural models that I think might help us talk about this kiddo. Should we chat about that?
Tracy: Yes, let us jump into that. In the show notes we will pop up one of the visuals I find really useful and often use, both in training and in my own clinical work. What I find helpful in clinical reasoning is to have some visual models, so that when you are doing an assessment, treating a child, consulting, or just trying to think it through, you can pause and reflect and organise your thoughts. Throughout this series we will share different visual tools like this, because in a podcast we need to be able to see what we are talking about sometimes, and a visual anchors us. One of the visuals is a flow chart that comes from the combined models around core development. The model is drawn from a neurodevelopmental treatment, or NDT, perspective, but it is also integrated from a sensory integrative perspective. Those two interventions are core to what we do in paediatric OT, and they really underpin the assessments you did, Cory. When you were testing this little guy, the tests themselves are measuring either speed of handwriting or a visual motor integration skill, but all of those things are related to underlying sensory motor functions, and we do not always have tests for those. So where clinical reasoning is really critical is in helping you interpret test data and observation data in a way that leads you to the clarity you need for a concise treatment plan, and for guiding teachers, school teams and parents. That gap between the data of the testing and the clinical treatment plan is fascinating.
Michelle: I am just thinking about it: what you are measuring is the output, and what we are going to talk about is the inputs, the underlying inputs that allow or facilitate or restrict him to handwrite, which is the output.
Tracy: Absolutely, that is a great way to think about it. If you think about sensory integration as the organisation of sensation for use, that is exactly what we are talking about. On some level Dr Ayres always wins. She has the framework that lets us zoom into the input, the underlying performance components, and ask how that is restricting the output in daily life and daily occupation. Here we are talking about the joy and purity and beauty of our profession, the piece people do not always understand, but when we get to it, it is so juicy and amazing. In this visual model the concept is to look at the sensory postural triad, and sometimes now we call it a sensory postural quad. We will get into why I added that. In the classic neurosciences there is a relationship between visual, vestibular and proprioceptive processing, and those are cornerstones of postural adaptation, in addition to the auditory partner, which makes the quad. So as you go to do an assessment and notice this 12-year-old was struggling with fine motor control, there were probably some really interesting findings throughout the postural system. You looked at clinical observations that included balance, reflex integration and anti-gravity control. Tell us more about those findings, and we will use this visual to organise our thoughts.
Cory: That sounds good. Even while he was copying the shapes or doing the fine motor control, there was a lot of shifting of body weight. He was using his right hand, and any time he had to draw on the left side of the paper he would shift his whole body over to the side, or turn. So I immediately started thinking about his midline and how organised he is in that space, and whether he can efficiently cross his midline without trouble. The fascinating thing was he asked me, do I have to hold the paper with my other hand? Something that should be super automatic. He has obviously been taught to do it, but he was propping himself up with that arm, and he said, do I have to hold the page, because I really want to hold myself up. When I came to do the handwriting speed test there was a lot of postural fatigue: holding his head up with his arm, and shaking, stopping what he was doing even though it is a three-minute timed test where you write as many words as neatly as you can. He would stop, shake his hand out, then lean on his head. There did not seem to be an urgency to what he was doing. And as he went through the test and fatigued, the legibility went right down.
Michelle: Did the size get bigger?
Cory: Size got bigger, and even the spacing between words went, so it was hard sometimes to see where he had ended one word and started the next. That test is not about legibility, it is purely about speed, but it gave me a good indication. If you are struggling with three minutes of writing, it is going to look pretty terrible if you have to do a whole writing task at school.
Tracy: Absolutely. And an assessment task.
Cory: Yeah. So any test where he has to write a decent amount is going to be really fatiguing, and then potentially he is not going to get the marks, because you cannot read what he is writing.
Tracy: That is exactly right. When you see handwriting drifting and the struggle happening pretty quickly, and then you also notice background postural difficulties straight away, it is going to be critical for this little one to have those postural functions better understood and addressed directly in intervention. You are not going to be able to build enough strength, work tolerance and skilfulness to sustain beyond a few minutes without the background postural system being able to automatically hold control and stability for long periods. By the time a child is 12, we would expect them to be able to write for long periods, 30 or 40 minutes, without a huge amount of fatigue, and this person is at about 10 per cent of what you would expect. So we want to back up and understand what is happening in that postural system. You mentioned midline orientation and crossing the midline, which were obvious. Sometimes the functions at the higher end of this visual chart are glaring and obvious. You will see midline stability hanging out at the top on the left-hand side. When kids struggle with midline function it is not obvious to everybody, but occupational therapists in particular are tuned into looking for it.
Michelle: It is fascinating that in a task of not many minutes he was already looking for strategies to accommodate for that. Whether he had sat at the desk for 10 minutes and was about to do a three-minute task, he was working it: I am going to put my hand here because I am already exhausted. So before he even started, he had strategies to work around his postural stability and midline challenges.
Cory: Before you even start, you can almost get a sense of what their postural system looks like by the way they sit in the chair, and the effort you can see them putting into the task. Sometimes you will see the mouth and tongue working, the jaw opening, all of that, to help get the hands to work. And you think, how hard it would be to be 12, working all day in class, and you cannot even sit and do these not-super-difficult activities for 10 minutes and comply. He was trying to do his best, but it was, I just need to put my hand here, asking so sweetly, do I have to put my hand there?
Tracy: How wonderful, because that is not necessarily the way every child copes, through being so sweet and cooperative. Especially when basic things like anti-gravity control, finding stability upright against gravity and maintaining it for a long time, are really hard, and fatigue comes over you, it is quite common for kids like that to start to feel a bit low and slow about the world, about themselves, about relationships. So the fact that this 12-year-old is finding a robust empathy and self-compassion is really cool, and I love that, but it does not help him at all with his postural control.
Tracy: So when we think about midline issues and look underneath, tell us about what you saw. You talked about how he was tipping off midline, not finding alignment. Sometimes we call that vertical righting, this upright, anti-gravity middle position. He slumps and leans. Sometimes kids do that because of low muscle tone, sometimes because their somatic sensory and vestibular sense of their midline is off, and sometimes because of fatigue and endurance and strength, which can be related to the muscle tone issue. But sometimes they also do it because every time you move off your midline it pulls for basic sensory motor patterns, and you can be stronger by fixing in a pattern rather than having the ease and fluidity of maintaining the upright posture. So there can be all kinds of things lurking underneath the description you have given. I am curious to hear more about the clinical observations you did.
Cory: I did the standard prone extension and supine flexion, rapid forearm rotations, finger-to-nose touching, the ATNR, the slow movements from the COMPS, and then some extras: standing on one leg, ocular tracking with smooth pursuits and saccadic eye movements, and a tonic labyrinthine reflex test.
Michelle: What was any movement like? I am interested in how he moved.
Cory: I did not do much catching or kicking a ball. I did some rolling, but otherwise mostly the standard observations. One of the most obvious issues, that struck me as really not pulled together for a 12-year-old, was his ocular tracking. His prone extension and supine flexion were really poor quality: lying on his stomach and trying to lift up, he found it really hard to get his legs, chest, head and arms off the ground, and he could not sustain it. He said, wow, that was really hard. On his back, going into supine flexion, he could not do it as one movement, so he lifted his legs, then his arms, then his head separately. The quality of chin tuck and flexion was not great, so he did not look very flexed in that position. I asked which was harder, and he said the prone extension. When I tested his tracking with smooth pursuits in the horizontal plane, he had massive jumps, his eyes really jumping away from the object at midline. I asked how he goes with reading, whether he ever skips words, and he said, oh yes, I have to reread the same line a lot of times to read it properly. It did not surprise me. Same with the saccadic eye movements: he overshot the mark, frowned and squinted, his eyes were watering, he was really working hard. I said we will not do too many more, because I do not like doing that test myself, so I feel for kids when they are working so hard at it.
Michelle: It sounded like you did not land on anything that came easy. It is cumulative, and then there is the affective load, what are you doing to me?
Cory: Exactly. I did really feel for him. The other fascinating thing was the tonic labyrinthine reflex test. I had him stand with feet together and hands at his sides, close his eyes, and I slowly tipped his head back in space and asked him to hold that position. He looked really uncomfortable, his eyes started fluttering, he was swallowing, his cheeks got flushed, and I thought he was going to fall over. I grabbed onto him so he would not fall, and he flinched really badly, a big startle. I said sorry, I thought you were going to fall. So I came away thinking there could even be a tactile processing piece, though I am not sure if it was that or just a fright because his eyes were closed. It seemed to fit with the quad you are talking about, this vestibular processing piece where he cannot get up against gravity, plus proprioceptive issues around where his body is in space, possibly some tactile issues, and definitely an ocular tracking issue. Does that give you more information about how he performed?
Tracy: Yes, absolutely. There are so many pieces. Using the visual graphic as an organiser, look at all the functions down the left-hand side. The functions you have described, he is really struggling with all of them: his alignment, stability and holding patterns are weak, and he has still-retained tonic reflexes. The tonic reflexes in anti-gravity control, in supine flexion and prone extension, become really critical observations when you have the clustering of difficulties this guy has. When you see that level of processing issue, it is very likely we are going to need to look specifically at the vestibular processing mechanism. The tonic labyrinthine reflex, the actual labyrinth, is the vestibular labyrinth, and that is what you are triggering. When you move the head-neck complex out of alignment, especially when you occlude vision, you do not have the horizon to organise around, and you are tipping the superior and inferior semi-circular canals deep inside the vestibular apparatus, which are set up to work in opposition to each other. A sudden influx of information as you tip the head changes the tonic activation of flexion and extension throughout your whole trunk and your extremities. Really importantly, the vestibular function organises not just in relation to the head-neck input but around the neck proprioceptors. The firing of the neck proprioceptors is what you saw with the visual flickering: as the head moves and the neck proprioceptors are stimulated, the nervous system recruits the visual partner to ask, what is going on out there, why are we moving, because my body is standing still but my head is moving. So the recruitment of information stimulates, through the MLF pathway, the medial longitudinal fasciculus, this neck-proprioceptor and vestibular complex that communicates up to the eye muscles and pulls on them to find out what is going on. When you occlude vision, you start to see automatic eye muscle movement, nystagmus, the eyes triggering to say, give me information, help me localise. The vestibular system, whenever it is moved, asks the whole postural system to find stability, and when it cannot, it becomes an autonomic event. It is so interesting, because now we have new theories, polyvagal theory in particular, that help us understand this differently, but Dr Ayres wrote about it back in the early 1970s. In the blue Sensory Integration and Learning Disorders book, she describes how when the tonic labyrinthine reflex fires off the way you just heard, you see it as an autonomic level of dysregulation, pretty low and deep in the nervous system. So this child is really struggling with a deep vestibular integration problem, and you are seeing it show up as weak postural adaptation, leading to weak ocular function, leading to weak handwriting. It goes all the way through the system, from basic vestibular function through postural adaptation into this daily life activity. It is a beautiful representation of Dr Ayres’ work, and of why the work we all do is so critically important.
Michelle: Wow, that has such a pervasive effect on him. I want to go back to the vestibular function. When we tilt the head backwards slowly, if the vestibular system is processing well, there should be no need to recruit. So if Cory is tilting my head back, typically I should not need to open my eyes. Is that right?
Tracy: Yes, once you have integration. When you have integration of this function, as you tip your head back you make postural adjustments. You are still feeling the somatic sensory sense of your body in space, you are connected to the ground, you know you are upright against gravity and you know you are not moving, because you have integrity in the vestibular and somatic sensory relationship. As you tip your head back you always get a differential firing of the muscle groups on the front and back of your body.
Michelle: That is to accommodate for the change in head position, specifically the vestibular system?
Tracy: Yes, it is to accommodate for it, partly because your centre of gravity has now shifted. If you are standing steady, everybody listening, just stand steady, orient your eyes on the horizon with your nose straight out, take a breath and feel your centre of gravity. Now tip your head back, and you will notice your centre of gravity rises, maybe two to five inches. That is because you have moved out of a balance in the sagittal plane of the flexion and extension muscle groupings and raised the centre of gravity, so now you have a differential firing pattern. If we put an EMG on you, you would have activation all the way through the muscle synergy, from the tip of your toes to the top of your head, compensating for that change in centre of gravity. Centre of gravity is where we align. Our three- and four-dimensional midlines are all organised around our centre of gravity and our base of support. So when the relationship between centre of gravity and base of support moves, there has to be a muscle response. Some people over-attribute that to the reflexes taking over. No, the reflex is there to help you. We all have that tonic labyrinthine reflex, but when you cannot integrate it, when you cannot adjust to your now higher centre of gravity, the relative muscle activation of the ventral and dorsal surfaces makes you feel disorganised, because you are used to your centre of gravity being lower than that.
Cory: So for him, because of the underlying issues processing information from the labyrinth, when you tip him he loses his sense of where his centre of gravity and base of support sit, and he does not know what to do with that information?
Michelle: He cannot automatically make the adjustments to accommodate for the change.
Cory: I was thinking about the sensation. When you said, everybody listening, put your nose straight out, take a breath, feel where you are, then tip your head back: because of the way our vestibular system organises, if we have integration we know what to do posturally with each change in centre of gravity, and without it we do not, so we recruit help. Is that right?
Tracy: That is precisely it. That is exactly the definition of postural adaptation. Postural adaptation is one of the most important automatic functions, staying integrated all day long as everything moves and changes, and it is one of the most primary products of sensory integrative processing. So postural adaptation is an outcome of quality sensory integration, of the real integrity of sensory integration. When you see a breakdown in postural adaptation like we see in this youngster, you are seeing a reflection of weak sensory integrative functions.
Tracy: So when you go to treatment-plan for a child like this, there are lots of different treatment approaches, and what we want is to not get stuck on any one of them but really work toward integration. We acknowledge there are difficulties with reflex integration. From an Ayres perspective, you work on reflex integration using enhanced vestibular and somatosensory experiences, but in a postural context, and sometimes people miss that. The idea is that you purposefully choose movement activities that put the child in positions requiring them to work in opposition to the reflexes that are disorganising them. For a tonic labyrinthine reflex, Dr Ayres wrote really specifically that you work in prone extension a lot. Because this youngster does not have organisation of prone extension anyway, we would have chosen that. We will use something like a scooter board ramp to get fast linear acceleration, building through the vestibular spinal pathway the quick fire of muscle tone, bringing in phasic activation and some anti-gravity control, and letting that vestibular activation drive the extensor muscle control. Once we have that priming, we work in active prone extension to build the strength of that tonic activation against gravity. That becomes almost formulaic in our treatment. Dr Ayres wrote it back in the late sixties and early seventies, and it remains so consistently true across different treatment approaches that it is really the cornerstone.
Cory: Can I clarify one thing? I am thinking about kids I have popped on scooter boards to get fast linear input into the vestibular system to fire up the extensor muscles. They often start with such poor quality, you are nervous about them even getting on the thing, they are not super aware of their body and sometimes run over their fingers. But after three or four goes you start to see it come on, as long as they are not truly afraid of vestibular input.
Michelle: Like a gravitational insecurity, where they truly will not get on the scooter board?
Cory: Right, those kiddos will not get on it. But otherwise you start to see it come on. So if I have a kid I have just done some fast linear input with down a scooter board ramp, is there a significance to it being downward-angled like that?
Tracy: Yes, there absolutely is. The tonic labyrinthine reflex communicates about the discrepancy in position between the superior and inferior canals, and when that relationship changes you get a different firing signal. When you are in a bit of head inversion it does two things. First, it orients so the superior canal is tipped forward, which activates extensor control more than flexor control, which is what we want here. Second, it activates, through the baroreceptors, a little dampening of the overwhelm that is happening autonomically.
Michelle: So a little inhibition, so he does not freak out, because this will feel intense for him.
Tracy: Exactly. So in treatment with a child you inch toward this. You do not impose fast linear activation if the kid is too afraid, or their experience so far has been that this is not successful and they do not enjoy it. We create the opportunity for it to be successful, because this is what we know the nervous system needs. You do not have to do it through a scooter board ramp. You can hang platform swings or lycra swings and invert them slightly to get the same activation, or use an inflatable, like a whale or a pillow, and do some moving on there. You explore movement, and your job as the clinician is to follow: how does that organise the child, where do they find joy and exploration, how do they pull the system together, and how do we start to see anti-gravity control improving. We want the vestibular activation to partner with postural adaptation, and then we work in postural adaptation, controlling against gravity, righting vertically, bringing the sagittal plane together through lateral and rotary movements. We pull in our knowledge of normal developmental movement patterns. So in the treatment sequence you weave across postural adaptation, from vestibular function up into postural control, following it carefully. This is also one of the interventions where, if we can add some sound activation, it is probably going to be a powerhouse for us, because the partner of sound with the vestibular apparatus gives a sense of synchrony and oscillation. That basic vibratory quality of somatic sensory input, grabbing the tone, the rhythm, the beat, fuels the deep proprioceptors, the deep somatic sensory receptors, and vestibular function. Together that creates a context rich enough that the postural adaptation system grabs onto the information in an integrative way. When I treat kiddos like this, I like to weave those pieces together, because it accelerates progress differently than if I do not.
Michelle: Because it adds another group of sensations to add intensity, or is it the base from which he can start to organise?
Tracy: It is really both. At the bottom of our chart it is the classic triad, but the auditory system is such a partner to the whole system. Our postural system gives us sustained anti-gravity control so we can be upright and engaged and use our eyes to scan and track, take in sound close and far, and use our extremities close and far. That adaptive function always includes organising your body in space, and the sound system helps you tremendously with that. At some point we will have an episode focused on auditory in particular. But here, in postural adaptation, we analyse the vestibular, somatic sensory, visual and auditory functions and purposefully use them to build the holding stability patterns, for the purpose of fluid movement off the midline, where the midline is always the reference point, for the core postural system, for gross motor actions, and for your eyes too. You talked earlier, Cory, about how he was struggling with ocular pursuit across the midline: as soon as he got to midline his eyes would jump. That is a particular ocular finding indicative of a vestibular-based processing issue underlying the ocular problem. As vestibular function starts to support postural adaptation and core postural development strengthens, you will see that prone extension become much more at ease, and one of the hallmarks is an elegant look to it. The integration of flexion and extension produces controlled anti-gravity control, with no break in the neck complex as the extension occurs. That tells you the vestibular and somatic sensory relationship is starting to organise, and once that happens you will see the ocular pursuit smooth out.
Cory: Let me recap, because this is easy to forget. We give input to the vestibular functions, ideally fast linear input with that slight inversion, going down the ramp head first, to provide input to the vestibular system. The system does some internal signalling that, for whatever reason, has not been efficient before now, and we enhance that so we can get better postural function, better uprightness. Then we go into the postural system, because that is where we are seeing such huge issues, to work on moving the body in space, finding alignment and enjoying the experience, because there is now activation to work off. Is that where we are going?
Tracy: That is exactly right. And then you have all kinds of fun opportunities to explore moving through space with different qualities, finding balance and equilibrium at different levels of dynamic and static challenge, and that system synchronises and organises. At the end of the day, postural adaptation is deeply related to functions like balance and bilateral coordination and midline, the skills at the higher end of the chart. As you work from the sensory base through the sensory motor functions that support it, that is what gives the background automatic capacity to be a handwriter that he does not have.
Michelle: I love that it is automatic. He should not have to think about it or plan for it, so that when he tilts his head back his body integrates that new input and adapts posturally to whatever demands the task is making.
Cory: And when it is not automatic, you get breakdowns in function.
Tracy: When it is not automatic, you have to lean on your arm and stop after two minutes, and it does not get better with practice. You only get better by addressing the underpinning. That is the beauty of the work we do. What a great taste, Cory.
Cory: Thanks, Tracy. We will put the link up in the show notes for that postural graphic that Tracy put together.
Tracy: That graphic has been adapted over the years, but it really came from Ann Grady, who was one of my bosses. She did a lot of teaching in neurodevelopmental treatment, but also taught courses on development and how we support kids in their development and occupational performance. So that chart was adapted from Ann Grady, years ago at Children’s Hospital in Denver, and it is a joy to share it in this form.
Michelle: It was really useful to unpack it using that image, so thanks for bringing it. Will that be accessible for everybody else too?
Cory: Have a look at it while you listen.
Cory: Thanks for listening, everyone. Each episode we are going to give you our key points from the discussion. For this episode, my first point is that the postural system is so vital for so many skills in our lives, and it has such a significant effect on handwriting function. The second thing I took away is that the vestibular system has such a profound effect on where I feel my centre of gravity is, and when my head position changes my centre of gravity feels so different. That was an aha moment for me. And the last thing was the power of fast linear movement for setting up good-quality extension. Thanks everyone. See you next time.
And that’s a wrap on today’s episode of Spirited Conversations. We hope this sparks something for you, whether it’s a new clinical idea, a fresh perspective, or just the reminder that you are definitely not alone in this work. If this conversation resonated, we would love for you to share it with anyone on their own learning journey. You can find information about the podcast on our website, and you can join us in the courses and communities the Developmental FX team have put together at developmentalfx.org. And if you’re enjoying listening, please subscribe or leave a review, it genuinely helps more people find us. Until next time, keep the conversations spirited!