CTSS Neurobiological Impacts of Trauma 1 — Questions and Answers
Question 1: Which brain structure is primarily responsible for processing and storing fear memories associated with traumatic experiences?
- Hippocampus
- Amygdala (Correct answer)
- Prefrontal cortex
- Cerebellum
Correct answer: Amygdala
The amygdala is the brain's fear-processing center and is hyperactivated during and after trauma, encoding emotionally charged memories with heightened intensity.
Question 2: The hypothalamic-pituitary-adrenal (HPA) axis is primarily responsible for regulating which aspect of the trauma stress response?
- Inflammatory cytokine cascade
- Cortisol and stress hormone release (Correct answer)
- Serotonin neurotransmitter balance
- Dopaminergic reward pathways
Correct answer: Cortisol and stress hormone release
The HPA axis governs the release of cortisol and other glucocorticoids, which mobilize the body's resources during a stress response and can be dysregulated in chronic trauma exposure.
Question 3: During an acute trauma response, which branch of the autonomic nervous system is first activated to initiate the fight-or-flight reaction?
- Parasympathetic nervous system
- Enteric nervous system
- Sympathetic nervous system (Correct answer)
- Somatic nervous system
Correct answer: Sympathetic nervous system
The sympathetic nervous system is rapidly activated during perceived threat, triggering release of catecholamines and mobilizing physiological resources for survival.
Question 4: Which neurotransmitter is most directly associated with the hyperarousal and fight-or-flight response triggered by trauma exposure?
- Serotonin
- GABA
- Norepinephrine (Correct answer)
- Acetylcholine
Correct answer: Norepinephrine
Norepinephrine (noradrenaline) is the primary catecholamine driving sympathetic activation during trauma, and its dysregulation is central to PTSD hyperarousal symptoms.
Question 5: Research consistently shows that chronic trauma and prolonged cortisol elevation result in what structural change to the hippocampus?
- Increased volume and enhanced neurogenesis
- No measurable structural changes
- Thickening of the hippocampal membrane
- Decreased volume due to glucocorticoid neurotoxicity (Correct answer)
Correct answer: Decreased volume due to glucocorticoid neurotoxicity
Elevated glucocorticoids from chronic stress cause dendritic atrophy and impaired neurogenesis in the hippocampus, resulting in measurable volume reduction observed in PTSD neuroimaging studies.
Question 6: The 'freeze' or tonic immobility response to overwhelming trauma is primarily mediated by which nervous system mechanism?
- Sympathetic activation co-occurring with parasympathetic activation (Correct answer)
- Pure parasympathetic withdrawal only
- Enteric nervous system override of cortical control
- Hypothalamic suppression operating in isolation
Correct answer: Sympathetic activation co-occurring with parasympathetic activation
The freeze response involves simultaneous high sympathetic arousal (internal activation) combined with dorsal vagal parasympathetic braking, creating a state of immobility despite internal hyperactivation.
Question 7: Decreased activity in the medial prefrontal cortex during trauma flashbacks primarily impairs which function?
- Heart rate and cardiovascular regulation
- Rational appraisal and emotional modulation of the amygdala (Correct answer)
- Muscle coordination and proprioceptive balance
- Long-term explicit memory consolidation
Correct answer: Rational appraisal and emotional modulation of the amygdala
The medial prefrontal cortex normally inhibits amygdala reactivity; its decreased activity during flashbacks removes this regulatory brake, allowing fear responses to dominate without rational appraisal.
CTSS Neurobiological Impacts of Trauma 1
Which brain structure is primarily responsible for processing and storing fear memories associated with traumatic experiences?