Greetings Earthlings! 🙂
In continuation from a previous post exploring coordination issues and autism, I’d like to dedicate a specific post to the often co-morbid issue of dyspraxia.
So what exactly is dyspraxia?
Dyspraxia, like autism, is a neurodevelopmental disorder that impacts a person’s ability to plan and process motor movements. It may also be known as motor learning difficulties, perceptuo-motor dysfunction, developmental coordination disorder (DCD).
Some of the general symptoms of dyspraxia include issues with balance and hand-eye coordination, poor posture, problems with fine motor skills (like picking up and holding items like a pencil or tying shoelaces), clumsiness and issues with spatial awareness and perception. It can also cause learning difficulties, but it generally does not impact intelligence.
So how are autism and dyspraxia linked?
Dyspraxia is caused by errors in the transmission of motor messages from the brain to the body. The neurological basis for the coordination issues associated with autism is poorly understood, however, it’s believed that they occur through a similar pathway to dyspraxia. The synapse (or connecting junction point between two neurons) is thought to play a major role in motor coordination. Autist’s have an overabundance of synapses compared to their normally developing peers, so with a greater number of brain connections comes the greater potential for signals to get lost en route to their destination.
Motor learning and control is influenced by a specific group of neurons known as purkinje cells. Purkinje cells, (located in the cerebellum- an area heavily involved in motor control), receive signals from climbing fibers- a type of neuron which carries information from the body to the brain. These climbing fibers detect changes or disturbances in our environment, such as changes in space or the position of nearby objects, and relay this information to the purkinje cells. Purkinje cells then emit inhibitory signals at synapses so to modify motor movements accordingly. In autism however, the efficacy of purkinje cells to influence motor change is greatly reduced.
Normally, each purkinje cell receives input from a single climbing fiber. As autists have too many synapses connecting the brain, the purkinje cell receives signals from multiple climbing fibers. This confuses the purkinje cell, which in turn alters the efficacy of corrective signals and motor movements veer off course.
In addition to this, dopamine deficiency is thought to disrupt motor learning at the synapses, which as I’ve discussed in many previous posts, is dysregulated in the autistic brain.
Roughly 80% of autists have issues with motor coordination, but not all will also have dyspraxia. It can be difficult to differentiate between the two conditions due to the high level of overlap in symptoms.
Hope you enjoyed this post dear Earthlings! 🙂
Have a lovely weekend!