16 Neuromechanics of Individuals with Dyspraxia
Evan Jackson
Introduction / about the author:
My name is Evan Jackson, at the time of writing I am in the final semester of my undergraduate study at Cal Poly Humboldt, majoring in Kinesiology with a concentration in pre-healthcare and minoring in music. I plan on going into Occupational Therapy (OT) after taking some time off after undergrad. The reason I am interested in OT is because I doubt I would be where I am without it. Growing up I felt like everyone was a step or 2 ahead of me, I had to work twice as hard to do what came naturally to my peers. I was very clumsy, had poor fine and gross motor skills, constantly running into objects, dropping things and hurting myself. I was (and still am) hyperactive, so that combined with my poor motor skills led to lots of accidents and injuries. My handwriting was abysmal and barely legible, but when I put a lot of work and effort into it it was barely passable so I made it through the first few years of school thinking I was just a little slower than my peers. Luckily my mom noticed that something was not adding up so she got me a diagnosis. When I was around 8 or 9 I was diagnosed with Dyspraxia, which allowed me to get the help I needed. I did occupational therapy for about a year then my mom worked on handwriting and at home therapies with me. I started taking parkour classes, which forced me to gain proper body awareness (aka proprioception, which is now one of my favorite senses! I go way more in depth in it later) and balance. At the time I had no clue how much the treatment I received helped me. I don’t know if I would have graduated from high school with how insanely difficult school was for me, but now I am about to graduate from college! I think that my story is an interesting case study about dyspraxia so I am excited to blend my experience with writing scientific papers for classes and my personal life experiences to help more people learn about and understand dyspraxia and the neuromechanics behind it!
Dyspraxia vs. Developmental Coordination Disorder and abbreviations used
Before I go further in depth about dyspraxia I have to address its other title, Developmental Coordination Disorder. Developmental Coordination Disorder (abbreviated throughout the rest of the chapter as DCD) is the term that is used in the Diagnostic and Statistical Manual of Mental Disorders volume 5 (DSM-V), so that is the term that is used in literature surrounding dyspraxia. I grew up calling it dyspraxia, so when I am discussing personal experiences and anecdotes I will use the term “dyspraxia” and when I am discussing literature and studies I will refer to it as “DCD”. For all intensive purposes they are the same thing, but dyspraxia is the label that I identify with more. In studies people with DCD are regularly compared to typically developing age matched peers as a control. When discussing such cases Typically Developing will be abbreviated to TD.
What is it?
According to the DSM-V there are four diagnostic criteria for DCD, which they categorize A-D.
A: Substantially below average execution and acquisition of motor skills compared to chronologically aged peers. These difficulties manifest as clumsiness.
B: Difficulties in motor skill in Criterion A significantly and regularly affect activities of daily living.
C: Symptoms present themselves in the early developmental period.
D: Deficits in motor skills are not better explained by an intellectual disability, visual impairment, or neurological condition which affects motor skills.
Prevalence: In children ages 5-11 years old the prevalence is anywhere from 5% to 8%. DCD is more common in males, the male:female ratio is between 2:1 and 7:1.
Now that you have some basic background about dyspraxia / DCD it’s time to get into the fun neuromechanics related details! The exact etiology of DCD is still unknown, but in this chapter we will explore the literature and see what people have found.
What causes Dyspraxia?
I was very accident prone growing up, I have a forehead scar that I got by running into a door knob which needed stitches, I fell off of a slide, hit my head and needed staples to close the wound, I ice skated too fast and fell, getting a concussion, and many more that I can not remember. According to my parents I went to the emergency room about 7 times before I was diagnosed with dyspraxia, which is about a once per year average. While some of these were genuinely not my fault (I was pushed off of the slide), most of them were in part because of my poor motor skills. But what causes these difficulties with both fine and gross motor control? Differences in processing sensory information is one of the primary beliefs behind the cause of DCD.
Sensory Information.
You know how everyone says learn to walk before you run? Let’s take that even one step back and look at just standing before we talk about walking. What goes on in your body to stay balanced? To answer the question we need to talk about my favorite sense: proprioception.
Proprioception refers to the sense of where our body is in space and the knowledge of where different body parts are relative to one another (Stillman, 2002). Proprioception occurs thanks to multiple sensory organs called proprioceptors that relay information from the peripheral nervous system to the central nervous system (Proske & Gandevia, 2012). The main two proprioceptors are muscle spindles and golgi tendon organs. Muscle spindles sense the change in length of muscles, meaning it detects muscle contraction and relaxation (Macefield & Knellwolf, 2018). They send information about muscles stretching to the brain which detects movement in the body (Macefield & Knellwolf, 2018). Golgi tendon organs are in the junction between muscles and tendons and detect the forces applied on tendons (Moon et al., 2021). The vestibular system detects the head’s position in space. It understands whether you are moving forwards, backwards, or side to side and if you are speeding up or slowing down, it provides valuable information about balance (Goldberg, 2012). Vision is a sense used to assess where the body is in space even though it is not specifically a proprioceptor (Stillman, 2002). Now that we understand more about the sensory information required for proprioception, how does this relate to individuals with DCD?
Sensory Information Integration
As discussed in chapter 1, sensory information is processed in the brain. Neuroimaging studies support the idea that brain anatomy differs in people with DCD compared to their TD peers. (Brown-Lum & Zwicker, 2015). Differences in brain structure mean that sensory information will be processed differently between TD people and those with DCD, leading to differences in cortical processing between these two populations (Elbasan et al., 2012).
An fMRI study that had both TD and children with DCD trace a flower while their brain activity was studied found that the two populations utilized different regions of the brain to complete the same task (Zwicker et al. 2010). The TD children utilized the parts of the brain responsible for spatial processing, motor control and learning, and error correction while the children with DCD used parts of the brain responsible for visuospatial processing (Zwicker et al. 2010). The parts of the brain that were activated for the children with DCD were the left inferior parietal lobule, right middle frontal gyrus, right supramarginal gyrus, right lingual gyrus, right parahippocampal gyrus, right posterior cingulate gyrus, right precentral gyrus, right superior temporal gyrus, and right cerebellar lobule VI (Zwicker et al. 2010). The parts of the brain that fired in the TD group were left precuneus, left superior frontal gyrus, right superior temporal gyrus/insula, left inferior frontal gyrus, and left postcentral gyrus (Zwicker et al. 2010). This supports the belief that sensory processing differs in people with DCD.
Not only does brain anatomy differ in people with DCD, but also white matter in the corticospinal tract (Brown-Lum et al., 2020). This further shows the difference in sensory processing between people with DCD and those without, as the corticospinal tract is the main spinal pathway from the neck down (Van Wittenberghe & Peterson, 2025).
There is limited but growing information about specific differences in the brain and spinal cord structure between people with DCD and people without. This is hypothesized to lead to differences in cortical processing of sensory information between these two populations. From Zwicker et al.’s study in 2010 we can see that visuospatial information is relied on more than motor and proprioceptive information in people with DCD (Zwicker et al., 2010). Potential experimental treatment for people with DCD can involve the completion of motor skills with eyes closed and / or blindfolded to train the brain to rely more on motor sensory information than vision.
Motor
Now that we know some of the possible explanations behind DCD, I’d like to share some really cool exercise and movement based treatment interventions to improve balance and proprioception. I really like the idea of exercise as medicine to treat people, and I believe in lowering the barrier of entry to exercising for as many people as possible so here is what I found about using bodyweight exercises to improve balance and proprioception in individuals with DCD.
There is limited literature which focuses purley on using bodyweight resistance to increase proprioception. The studies that explored utilizing a strength training program featured different forms of resistance and some certain bodyweight exercises. Kordi et al. utilized a Thera-Band for a majority of their intervention exercises for children with DCD aged between 7 and 9 years old (Kordi, 2016). The Thera-band was used for increasing lower limb muscles while body weight resistance was used to increase core strength and the gastrocnemius (Kordi, 2016). Kordi et al.’s intervention significantly increased static balance skills, but not dynamic balance skills (Kordi, 2016). While body weight resistance was utilized in this study, it is not possible to tell what percent of the proprioceptive benefits were from simply bodyweight exercises.
Kaufman et al. implemented a strength training program for a five year old with DCD and found that it led to improvements in gross motor function and proprioception (Kaufman & Schilling, 2007). Their intervention had both weighted resistance and bodyweight resistance. As the test subject was only five years old very light weight was utilized, the resistance being between 2-lb and 5-lb. Four out of the ten exercises in the program utilized purely bodyweight resistance and one of the ten started with no resistance and resistance was added as strength increased. The body weight exercises targeted the abdominals, back extensors, ankle dorsiflexors, and ankle plantar flexors. The ankle dorsiflexor and plantar flexor exercises were balance based, so initially the subject held on to a table for support but at the end of the 12 week intervention they did not use any support. Improvements were found in both static and dynamic limb position awareness. Similarly to the last article studies, it is unclear to what degree the increases were purely because of body weight resistance, but we see that body weight exercises have a positive effect of proprioception.
Zolghadr et al. examined the effects of balance correction exercises on people with DCD (Zolghadr et al., 2019). Their experimental program took 8 weeks, 3 days a week, 60 minute sessions, and was split into 2 4 week stages. The balance exercises included heel-toe walking, walking on a line, sideways walking, reverse walking, zigzag walking, walking with long steps, tandem standing, standing with feet together standing on one foot, and weight transfer (Zolghadr et al., 2019). The corrective exercises used bodyweight resistance and included posture correction, neck extension, cat stretch, plank, V shape movement, and bridging on a swiss ball (Zolghadr et al., 2019). Intensity was adjusted as the intervention went on based on the subject’s power. According to the post test results the experimental group had significant increases in static and dynamic balance in relation to the control group (Zolghadr et al., 2019). Increased stimulation of proprioceptors leads to better balance (Zolghadr et al., 2019), so through this study we can conclude that body weight exercises can improve proprioception.
Balayi et al. implemented a combined physical training and Hemsball training intervention for children with DCD. The physical training aspect of the intervention included body weight exercises using a hemsball (Balayi et al., 2022). The exercises included upper-body roll outs, inclined press-up, contralateral single-leg hold, and quadruped exercise, 3 sets were done with 3 repetitions and 30 second rests. The cycle was then repeated with 2 sets of 3 repetitions and 30 second rests (Balayi et al., 2022). Their findings show that dynamic and functional balance improved in the intervention group when compared to the control group thanks to physical training and core stability (Balayi et al., 2022). Since Balayi et al. ‘s intervention also included coordination training it is unsure to what degree body weight exercise contributed to the increases seen.
Dana et al. examined the effect that virtual reality exercise has on dynamic balance in children with DCD. They utilized Wii Fit balance (tilting table, penguin sliding, and balance bubble) and aerobic games (basic stepping) in their intervention. The virtual reality group participated in 12 Wii Fit sessions for 30 minutes weekly under the supervision of a therapist. Dana et al. found that there was significant improvement in the dynamic balance in the intervention group. Since no weight or resistance was utilized in the treatment, we can say that bodyweight virtual reality training can improve balance, which is because of an improved proprioception.
Fong et al. studied the effects of taekwondo on sensory organization and balance control in children aged 6-9 with DCD. The intervention included a taekwondo training group (DCD-TKD) which was a 12 week program that met once a week for 1 hour sessions. A physical therapist and skilled taekwondo practitioner modified a typical taekwondo syllabus to better suit the subjects. To reinforce training each subject was given take home exercises to be performed daily. They found increases in standing balance and vestibular function (Fong et al., 2012).
Final Thoughts:
I had so much fun writing about dyspraxia, this is such an important topic to me that not a lot of people know about. Throughout my career I plan on learning as much as I can about people with dyspraxia, what causes it, and how to mitigate the negative effects. I hope that you enjoyed reading my chapter entry and have learned something new about dyspraxia.
Works Cited
Goldberg, J. M. (2012). The Vestibular System: A Sixth Sense. OUP USA.