Friday, November 18, 2016

Understanding the Brain's Response to Stress and Threat



Understanding what causes anxiety or the “flight or fight” response…
What happens to the brain when placed under stress or threat?
The Brain’s Response to Stress and Threat
  • The thalamus senses threat, and sends signals to the amygdala and orbitofrontal cortex.
  • The amygdala stores/pulls up unconscious memories. Once signaled, it triggers the sympathetic response via the hypothalamus. The hypothalamus fuels and runs both the sympathetic and parasympathetic stress systems.
  • The hippocampus then provides conscious memories, placing events in context of space and time.
  • The cingulate reasons with the amygdala and asks the frontal cortex areas for help with the process.
  • The frontal cortex areas assess the situation, weigh options, plan and reason with the amygdala.
What is the amygdala and what role does it play in this response?
The Amygdala
The amygdala is a primitive part of our brain that keeps us alive. It stores unconscious emotional memories and triggers the body’s responses to stress and threat under stress. It also contacts the hypothalamus and sets the autonomic nervous system in motion.
The amygdala is very much like a “guard dog”. It cannot see or hear subtle differences in signals it receives from the thalamus, and it lacks conscious memories. Its memories are unconscious, primitive, and fragmented—very much like “flashbulb memories” of sound, image, scent and emotion. In its efforts to protect us, it will pull up any memories that might be related to incoming signals. That is the reason why a gunshot and champagne cork popping are all the same to the amygdala and to the mind of a veteran.
**Each time these emotional memory fragments are triggered and re-experienced, the veteran can actually be traumatized by the memories themselves, even if there is no real threat in the present.

What is the autonomic nervous systems? What role does it play in my veteran’s PTSD/anxiety symptoms?
The autonomic nervous system controls our heart rate, breathing, metabolism, energy,
perspiration, etc. It works toward balance, and has two “arms” that rise and fall in turn:
• The sympathetic nervous system, the one that speeds up processes (heart rate,
breathing, metabolism, energy, etc.) and tightens muscles
• The parasympathetic nervous system, the one that slows down these processes and
relaxes muscles
The body’s responses to stress and danger tend to fall into these two categories, sympathetic
and parasympathetic. They are meant to operate in gentle allostasis (use of change to achieve stability), with the sympathetic side rising to fight or flee from temporary threat, and the parasympathetic rising to keep us safe when we are helpless—and to quiet down the sympathetic and return us to homeostasis (a relatively stable state of equilibrium).
A useful tool for keeping these two terms straight might be to think of the sympathetic nervous
system as being “sympathetic” toward our initial need to run from danger, and the parasympathetic as being the opposite and balancing reaction.

What is the hippocampus and how is it affected by stress?
The Hippocampus
The hippocampus is responsible for the ability to store and retrieve memories. People who have experienced some kind of damage to their hippocampus experience difficulties in or the complete inability to store and recall information. Along with other limbic structures, the hippocampus also plays a role in a person's ability to overcome fear responses. Many people with PTSD experience memory-related difficulties. They may have difficulty recalling certain parts of their traumatic event, or alternatively, memories may be vivid and always present. People with PTSD may also have problems overcoming their fear response to thoughts, memories or situations that are reminiscent of their traumatic event. Due to the hippocampus' role in memory and emotional experience, it is thought that some of the problems people with PTSD experience may lie in the hippocampus. Researchers, using MRI’s, have been able to determine that the hippocampus or veterans with PTSD has actually suffered damage. They believe this damage may be under stress.

What are the psychological or mental changes in the veteran as a result of the damage to these areas of the brain?
  1. Hostility/Aggression. Our veterans were accustomed to longer periods of time overseas in which they were allowed and encouraged to be hostile in order to stay alive. Because of this, once they return home some veterans may respond differently to challenges or “threats” than civilians.
  2. Guilt. Many veterans have what is called “survivor’s guilt” as a result of witnessing their friends and battle comrades get seriously injured or killed. The lingering questions of “Why didn’t it happen to me?” and “What else could I have done to prevent it?” often haunt a veteran’s mind.
  3. Depression/Suicide. Veterans suffering from PTSD are seven times more likely to have depression and suicidal thoughts.
  4. Paranoia. When in Iraq/Afghanistan, a paranoid soldier stays alive. Everything is considered a potential threat, even a child on a bicycle. That hyper vigilant stage is extremely difficult for a soldier to put “at ease” once she returns home. Also, the damage done to the amygdala under those extreme and prolonged environments of stress can keep the veteran in that “flight or fight” response mode for months to years after returning home.
  5. Lack of trust. When overseas, the soldier maintains a limited circle of trust amongst his battle comrades in order to stay alive. Everyone and anything else outside of that circle in those extreme environments are considered untrustworthy and potentially dangerous. Once a soldier returns home, it can be very difficult for him to reestablish that same trust with others, even some family members and spouses.
  6. Poor coping skills. As a result of their traumatic experiences, many veterans are overwhelmed and hypersensitive by too much noise, too many people, too many changes, or too much stimuli of any sort. What may be deemed “normal” circumstances to us are not normal to the veteran.  For example, while watching a fireworks display during a local festivity may be exciting for you, the veteran may be terrified and begin to panic at what may sound to him very much like sporadic gunfire.
Understanding hyper vigilance and other combat PTSD symptoms…
What is hyper vigilance?
Hyper vigilance is one of the hyper arousal symptoms of PTSD and refers to the experience of being constantly tense and "on guard." A person experiencing this symptom of PTSD will be motivated to maintain an increased awareness of their surrounding environment, sometimes even frequently scanning the environment to identify potential sources of threat. Hyper vigilance is also often accompanied by changes in behavior, such as always choosing to sit in a far corner of a room so as to have awareness of all exits. At extreme levels, hyper vigilance may appear similar to paranoia.
Coping with hyper vigilance…
Common compulsive behaviors of hyper vigilance…
  • Peeping out the windows, making sure blinds/curtains are closed
  • Making sure all doors are locked in house and cars
  • Keeping certain items in order at all times
  • Patrolling the house at night
  • Checking the perimeters outside the house
  • Setting curfews and lockdowns for the family
  • Scanning exits, entrances, and crowds in public places
  • Having to sit facing the exits and entrances in restaurants and buildings
  • Holding onto you or the children in crowded, public places
Know and understand the triggers that may spark the hyper vigilant behaviors in your veteran…
Why are many veterans with PTSD compelled to be so vigilant?
On one hand, soldiers are trained that everything has its place and must be in that place. On the other hand, many of these behaviors that are drilled into soldiers became second nature (for many, first nature) and that meant they saved lives. Hyper alertness on the battlefield, or in a terrorist situation, or patrolling streets in Afghanistan and Iraq saves lives.
Because of this, veterans are PTSD hyper vigilant because:
1. Their military training taught them to be hyper vigilant.
2. Their brains were trained to expect danger at any moment.
3. Their hyper vigilance kept them and others alive (usually).
**Your veteran experienced danger and lived through it because of his training. Therefore, his body and soul has been conditioned to stay on constant alert, always ready for trouble. This is fine if you are on a patrol or serving in a combat zone, but it does not help when you are trying to live a “normal” life as a civilian. The problem is that the service never taught your veteran how to turn off his hyper awareness. He may have been discharged and left wound up tight inside - without any teaching or warning that he might have PTSD and exhibit hyper vigilance as part of the PTSD-Identity.
**Your veteran may not be getting the proper amount of sleep at night due to his hyper vigilant behaviors. Check with his doctor to see if any sleep medication or other methods of “winding down” at night may help your veteran get the sleep his needs.
**Be mindful of overstimulated environments which may provoke a negative response from your veteran. While some environments may be unavoidable, be prepared to find an “escape route” if necessary. You may want to introduce your veteran to certain stimuli in small increments rather than risking the panic of overstimulation. Let him get adjusted to different environments in small increments of time. For example, allow him to sit in the back of the auditorium during a child’s dance recital rather than sitting up front. He may be able to deal with the noise and incoming crowd easier that way.