“The brain is a monstrous, beautiful mess. Its billions of nerve cells - called neurons - lie in a tangled web that displays cognitive powers far exceeding any of the silicon machines we have built to mimic it.”
–William Allman, Apprentices of Wonder
A hierarchy is a set of things organized into layers. Your brain has a hierarchy in which the top layer usually manages the layers beneath. The top layer in the brain’s hierarchy is the cortex, which includes the prefrontal cortex, which helps us to reason, use language, and imagine. Down a step in the hierarchy is the limbic system – the emotional brain which influences the way we relate to others. The bottom level of the hierarchy is the brainstem, which manages regulatory functions like breathing and heart rate (“The Structure and Function of the Human Brain,” 2019).
This hierarchy is usually the order of things, but there are exceptions; When a woman is threatened, her thinking brain gives way to her emotional brain and she acts on instinct in order to survive.
Brain cells that transmit information are called neurons. Most neurons are separated by tiny gaps called synapses. Neurons send chemicals called neurotransmitters across the gaps to message other neurons, sending signals of our sensations, thoughts and emotions (Brookshire, 2017).
Nerves are lines of communication that run through the body to the brain and are organized into various systems. We’ll focus on the Autonomic Nervous System (ANS). The brain uses the ANS to communicate with other organs.
The ANS is made up of two parts: the sympathetic (SNS) and parasympathetic nervous systems (PNS). The sympathetic nervous system “revs” the body for vigorous activity. The parasympathetic nervous system facilitates reduction in heart rate and other non-emergency responses (Kalat, 2013).
Trauma has significant impacts on the ANS, as threats activate both the sympathetic and parasympathetic nervous systems. In particular, childhood trauma can affect a woman’s lifelong ability to regulate the SNS and PNS systems when experiencing even minor stressors.
The below image depicts the Autonomic Nervous System (ANS). On the left, the parasympathetic nervous system is detailed; this system regulates day to day internal behaviour and processes. On the right, the sympathetic nervous system is depicted; this system regulates processes and behaviour during stressful situations, often with no conscious thought/awareness. Trauma often leads to dysregulation of the Autonomic Nervous System.
Note: Click on either the Parasympathetic Nervous System
or Sympathetic Nervous System to learn more.