Thursday, December 21, 2006

Cognitive Effects of Trauma and PTSD

Typical cognitive effects after a traumatic experience:
-Recurring intrusive thoughts
-Flashbacks
-Memory lapses
-Difficulty with focus, concentration and sustained attention


It is difficult for a person who is traumatized to learn new things. There is a sense of being scattered, distracted and unable to focus on work or daily activities. Making even simple decisions might seem overwelming.

Feeling overwhelmed: It can be difficult to sort out relevant matters from the daily bombardment of information.

Negative perceptions: The world seems threatening after a traumatizing experience. Partly this is due to flashbacks and environmental triggers. There is also a bias toward noticing things that are worrisome or frightening.

Recurring memories and nightmares replay the same experience, over and over again. Research by Bessel van der Kolk observed that the content of the nightmares of veterans with PTSD stayed the same for 15 years.

Unlike normal, narrative memories, which fade over time, traumatic memories remain fixed, timeless and contemporary, delivering the same dramatic punch every time.

Why do our brains work this way? The flood of hormones in response to trauma both gives us the energy to fight/flee danger and imprints the memory of that trauma in order to create a once-and-forver learning experience. It is a survival mechanism, so that if a similar danger comes again, we will be wired to instantly react.

Traumatic memories are processed and stored differently than memories of ordinary events. "Normal" memories are encoded verbally, and thereby can be verbally communicated to others afterwards. But traumatic memories are experienced as emotions, sensations and physical states.

The trauma survivor faces an odd contradiction. The memories are so vivid, rich with emotional and sensory details. Yet it's difficult to put words to these experiences, to make cognitive sense out of them.

The phrase "speechless terror" is not a hyperbole; people literally cannot talk when affected in this way. PET scans demonstrate the physiological basis of this phenomenon: during flashbacks, oxygen levels and the verbal centers of the brain are affected.

Source:
Naparstek, Belleruth. Invisible Heroes. NY: Bantam Bell, 2004.

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