January 21, 2013
A friend of mine, an extremely talented Speech-Language Pathologist, texted me a few days ago. “Can you explain in 4 sentences or less the connection between movement and readiness for learning in children with low tone?” she asked. All of a sudden I felt like I was on Jeopardy! – I’ll take the vestibular system for $400!
(I chose to take her request for 4 sentences as a reflection of her incredibly busy schedule rather than my preference for nerdy, long-winded conversations.) Here’s my answer.
Low tone is thought to be related to an impairment of the vestibular system at some level, as the vestibulospinal tract serves axial and antigravity muscles. The vestibular system also has connections with the reticular activating system (modulating arousal) and the limbic system (modulating emotion). Movement therefore provides input to axial and antigravity muscles as well as input to the reticular activating system and the limbic system. All of this input combines to support the neurological arousal required for attention, which is necessary for readiness to learn.
So there it was, 4 sentences. I was very pleased with myself, but it wasn’t to last.
The next text came. “Thanks…..what is the relationship to parasympathetic system, if any??” OK, now for the daily double.
The limbic system has inputs to the autonomic nervous system (ANS) and influences the balance between the sympathetic nervous system (SNS; fright/flight/fight) and the parasympathetic nervous system (PNS). If there is altered vestibular input, there will be altered limbic system input and therefore, altered SNS/PNS balance.
The vestibular system also provides input to the diaphragm, providing modulation of our breathing with the influences of gravity. Deep breathing inhibits the SNS via the baroreceptors at base of esophagus, effectively increasing the influence of the PNS. If there is decreased input to the diaphragm from the vestibular system, there will be altered diaphragm activity and a decreased inhibition of SNS. SNS dominance can result.
So that was my minute on Jeopardy! Did I miss anything you would have included? Let me know, I’d love to keep the game going!
OK, now I have to share this with my SLP comrades!
Thanks Christine, SLPs have such a great knowledge base and it is so different from ours – makes for great conversations over coffee!