Understanding the nervous system, brain and muscle connection
The nervous system is the control center for your body. It interprets the things your body senses, and it sends information to the muscles and glands telling them what to do.
The nervous system includes the central (CNS) and peripheral (PNS) systems.
The central nervous system includes the brain and spinal cord, and the peripheral nervous system includes the nerves that branch out from the spinal cord and the brain the periphery of the body.
The somatic nervous system regulates the movement of skeletal muscles, and the autonomic nervous system controls involuntary actions such as heart rate, digestion, and perspiration.
Neurons are the building blocks of the nervous system. Each neuron has a cell body with extensions called dendrites and an axon. Dendrites are the receiving part of a neuron. The signal received at the dendrite is transmitted toward the cell body of the neuron in the form of an electrical impulse. The impulse is transmitted away from the cell body to another neuron, muscle, or gland by the axon, which terminates at a synaptic bouton.
The brain can be referenced into 3 areas:
1) Forebrain, known as Cerebral cortex, containing two hemispheres broken down into 4 lobes: frontal lobe, parietal lobe, occipital and temporal. The forebrain is the central processor of information, governs complex cognitive function, controlling emotions, memory, thoughts, judgement and all voluntary actions.
2) Mid-brain, between fore and hind brain, containing the tectum and tegmentum – controls motor movement, related to the eyes, auditory and visual processing.
3) Hind brain, known as Subcortex, containing the medulla oblongata, the pons and cerebellum. This part of the brain coordinates autonomic functions fundamental to survival, including respiration, motor activity, sleep and wakefulness.
Cerebellum (is the) section of the brain that coordinates sensory input with muscular responses, located just below and behind the cerebral hemispheres and above the medulla oblongata. The cerebellum integrates nerve impulses from the labyrinths of the ear and from positional sensors in the muscles; cerebellar signals then determine the extent and timing of contraction of individual muscle fibres to make fine adjustments in maintaining balance and posture and to produce smooth, coordinated movements of large muscle masses in voluntary motions.
So to recap… this is important
The Cerebral Cortex governs voluntary functions such as conscious learning, the act of performing new and novel activities, re-building neural pathways to maintain control over movement. The repetition of these movements over time becomes automatic and then the responsibility of these movements shifts to the subcortex of the brain.
The Subcortex governs autonomic functions of the body such as heart rate and breathing, but also behaviors and movements that have become habituated, like brushing your teeth with your dominate hand, or leaning to one side and hiking your hip quickly off an injured ankle, resulting in a shortened side waist and tight trunk muscles leading to hip height discrepancy and imbalanced movement.
Further explained..."The subcortical structures of the nervous system have complex motor and non-motor functions. They are situated beneath the cerebral cortex, and receive extensive inputs from it and the peripheral sense organs and stretch receptors. Through recurrent feedback loops, the information received is processed and integrated to provide an output that contributes to scaling, sequencing, and timing of movements, in addition to learning and automatization of motor and non-motor behavior."
The take home point is that the subcortex controls learned and habituated movements patterns whether they benefit us or not!
This is a critical distinction when it comes to the world of somatic movement re-education, because working somatically addresses “unconscious” habituated movement patterns and reflexes and brings them back under the control of the cortex of the brain, "re-educating" and "restoring muscles natural resting state", releasing trauma and restoring balance in posture and movement patterns.
Text Head Forward Syndrome
Another great example of a habituated movement pattern under the control of our subcortex (outside our voluntary control) is text neck forward syndrome.
This recently coined digital age diagnosis is caused by prolonged periods of looking down at a mobile device or at a computer, resulting in chronic shortening of the flexors of the neck, shortening and rounding of the upper arm bones and pectoral muscles and a rounding of the upper thoracic spine - a Red Light Reflex display.
Essentially, the "syndrome" is a habituated movement pattern or a complex display of sensory motor amnesia. Individuals that have spent too much time in this head forward position whereby the nervous system has learned and made the position permanent, even after putting the device away.
Thankfully, Thomas Hanna’s Somatic movement model can permanently re-educate the aforementioned muscles to length restoring proper posture, restoration of balanced posture and an elimination of neck discomfort and pain.