CHAPTER 10: THE YOGA CLASSROOM • 215aspects of the body critical to self-regulation (Cook-Cottone, 2015; Levine, 2010; Porges, 2011).
Recent research suggests that these systems are a bit more complex than originally under-
stood and are involved in the regulation of physiological, emotional, and relational aspects of
self (Porges, 2011). Specifically, the nervous system comprises the central nervous system (the
brain and spinal cord) and the peripheral nervous system (Levine, 2010), which comprises the
autonomic nervous systems (maintains homeostasis and regulates organs and metabolism)
and the somatic nervous systems (involves voluntary muscle control, touch, and propriocep-
tion; Levine, 2010). Feeling triggered and in reaction involves the autonomic nervous system,
which comprises two systems, the sympathetic nervous system (fight or flight response) and
the parasympathetic system.
The vagus nerve, the 10th cranial nerve, plays a substantial role in the dynamics of these
systems and in self-regulation (Porges, 2011). The Latin word vagus means wandering. It is
called the wandering nerve because it has multiple branches that begin in the cerebellum
and brainstem and reach through the core of your body and connect to the heart and other
major organs. The vagus nerve was named by the German physiologist, Otto Loewi, who dis-
covered that stimulation of the vagus nerve released acetylcholine reducing the heart rate.
Today, the vagus nerve is believed to play a role in the calming response from deep breath-
ing, and the parasympathetic nervous system in the rest-and-digest and tend-and-befriend
responses. When the vagus nerve is functioning well it is said to have higher vagal tone,
which is associated with a decrease in inflammation, blood pressure, depression, and nega-
tive moods, and increase in positive emotion, physical health, and social connection.
More specifically, the parasympathetic nervous system functions through what is
believed to be two subsystems: (a) the unmyelinated primitive vagus system associated
with immobilization and shutdown, and (b) the myelinated vagus system associated with
social engagement and muscles in the face, middle ears, and throat (Levine, 2010). When a
person is in a safe environment, the parasympathetic nervous system also promotes func-
tions that are associated with rest, growth, and restoration; the sympathetic nervous system
promotes increases in metabolic output to negotiate challenges that come from outside of
the body (Porges, 2011). It is believed that when threatened or challenged, the nervous sys-
tem works in a problem-solving hierarchy (see Table 10.1).
It is believed that these systems activate in the face of both real danger and perceived dan-
gers (Levine, 2010). Individuals who have been chronically traumatized, abused, or neglected
can experience a domination of the immobilization or shut-down system (Cook-Cottone, 2015;
Levine, 2010). Those who have experienced acute trauma or challenge may be more dominated
by the fight-or-flight system (Levine, 2010). Choice is lost and self-regulation problems can fol-
low. It is important for teachers to keep in mind that: (a) there are physiological foundations for
emotional regulation and self-regulation, and (b) dysregulation of these systems can play a role
in self-regulation challenges (Cook-Cottone, 2015). Yoga is an integrated system of tools that can
support neurological integration, down regulation of sympathetic (i.e., defensive or reactive)
and immobilizing parasympathetic responses, increases in reflective engagement, and promo-
tion of health, strength, and flexibility (Cook-Cottone, 2015; Field, 2011; Levine, 2010). That is,
yoga can help. Levine (2010) states, “Somatic approaches can be enormously useful, or even
critical, in [the] healing effort” (p. 115). Embodied practices help move students from immo-
bilization and reaction and toward equilibrium and social engagement (Cook-Cottone, 2015;
Levine, 2010). For a review of interpersonal neurobiology, see Siegel (2012); for an extensive
review of the research on the vagus nerve, see Porges (2011); and for an exploration of trauma
and the body, see Levine (2010).