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Origins of Chronic Illness Part I

The Brain
I. The Role of the Nervous System in Regulating the Mind and Body
Symptoms, such as high blood pressure for example, represent a change in the regulation of a natural process. In a healthy state, the nervous system increases blood pressure as part of the normal "fight or flight" response to help provide oxygen and fuel to the brain and other vital organs when we become active or survival is at stake. From a somatic psychology perspective, symptoms represent intelligent, if maladpative, attempts by the body and mind to cope with challenging circumstances.

The nervous system interacts with and regulates all other organ systems in the body. The nervous system has many components, and the autonomic nervous system, which regulates activities that occur outside of conscious awareness such as blood pressure, heart rate and digestion, is of particular interest for understanding origins of symptoms. The autonomic nervous system (ANS) regulates and interacts with the immune system, hormones and the endocrine system, digestion and the gastrointestinal system, heart rate / blood pressure and the cardiovascular system, etc....

The ANS learns to regulate from interaction with the world. Non-genetic factors play an important role in teaching our ANS how to respond to stress and how to maintain balance (homeostasis). This capacity for self-regulation is therefore learned, and environmental factors that train our ANS contribute to our risk for physical and emotional symptoms, as well as for chronic illness.

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II. The Nervous System Interacts with and Regulates all other Organ Systems
The Nervous System is designed to keep our minds and bodies in a state of balance: also known as "homeostasis". Anything that affects this balance, whether coming from the inside (such as hunger, the need for oxygen, fear) or the outside (such as temperature change, movement, watching a movie), require a change from one state of balance, such as hunger, to another, such as digestion. These changes are faciliated by the autonomic nervous system, which regulates processes outside of our conscious control.

Change represents Stress

Change requires an organism to adapt in order to maintain or regain balance. Anything that requires adaptation represents a form of stress, regardless of whether the change is unconscious or whether it is "positive" or "negative". Unconcsious activities occur when we eat, which requires a change of state from hunger to digestion); or move from a sitting position to standing, which requires an increase in blood pressure to circulate blood against gravity and to maintain consciousness. An example of "positive" stress includes marriage, good food, and job promotion, whereas "negative" stress is suggested by cold, threat, and job loss.

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III. The Autonomic Nervous System (ANS)
Normal moment-to-moment activities such as digestion and blood flow are regulated by the autonomic nervous system (ANS) which is made up of two components or branches: the sympathetic nervous system and the parasympathetic nervous system .

The Sympathetic and Parasympathetic Nervous Systems

The sympathetic nervous system (SNS) is a branch of the ANS that is familiar to most of us because it supports the survival mechanism of fight or flight. In general, the SNS supports activity and movement by increasing blood pressure and heart rate, and by distributing oxygen and promoting the release of stored fuel such as sugar.

The less known parasympathetic nervous system (PNS), the second branch of the ANS, is most active when we feel safe, and allows us to rest and recuperate in preparation for our next activity, as well as to reproduce. This PNS facilitates digestion, the storage of food as fuel, and sleep.

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The ANS maintains balance and homeostasis by the combined action of the SNS and PNS, which oscillate up and down as they increase and decrease activites that affect the whole body (such as heart rate) or a specific part of the body (such as increasing temperature in the hands or delivering fuel to the brain). In health, these two branches work together to adapt to ongoing minute changes in the external and internal environment (see Figure 1).

sinus wave curves showing homeostasis
Figure 1. Homeostasis.

The nervous system fosters homeostasis by maintaining balance between rest (Parasympathetic nervous system) and activity (Sympathetic nervous system).

A healthy ANS responds fluidly to changes and stressors in the environment and easily maintains homeostasis, both in our inner and outer worlds, and between our bodies and minds (see Figure 2).

sinus waves vary in size depending on degree of rest or activity
Figure 2. Maintaining Homeostasis Across Activities.

A healthy nervous system maintains homeostasis by balancing input from both branches of the ANS during activites ranging from relaxing, digesting and sleeping (PNS), to waking, feeling excited, and running (SNS).

Operating within Boundaries

In health, the ANS operates within boundaries. Following a state of activity such as work, play, or exercise (SNS) a healthy organism switches to a state of recovery (PNS). Then, when someone has rested or slept (PNS), the sense of being restored motivates a switch to activity once again (SNS). In contrast, trauma and disruptions in early life facilitate greater risk for living in states beyond the boundaries. These states can involve extremes of life tolerance, such as high arousal, fear, and vigilance on the sympathetic (SNS) end of the spectrum, or hibernation and loss of sense of self (dissociation) on the parasympathetic (PNS) end (see Figure 3).

variable sinus wave curves if homeostasis operating within upper and lower limits
Figure 3. Operating within Boundaries.

A healthy system remains within certain maximal limits or boundaries.

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IV. Examples of Activities Regulated by the Sympathetic and Parasympathetic Nervous Systems

Sympathetic Nervous System
blood pressure
heart rate
fuel availability (sugar, fats...)
oxygen circulation to vital organs
blood clotting (minimizes loss of blood if wounded)
pupil size and peripheral vision (improves vision)
fuel storage (decreases insulin activity)
Parasympathetic Nervous System (PNS)
intestinal motility
fuel storage (increases insulin activity)
resistance to infection
rest and recuperation
circulation to nonvital organs, (skin,extremities...)
endorphins, the "feel good" hormones
heart rate
blood pressure

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© copyright 2004-2019 | Veronique Mead | all rights reserved | learn more on my active blog Chronic Illness Trauma Studies