Gilbertson et al. (explanations for disorders)

Question 1

key terms

Answer 1

PTSD
hippocampus (brain part associated with learning and memory)
MRI
etiology (a cause of a disease)

Question 2

aim

Answer 2

to see if low hippocampal volume is a risk for PTSD

Question 3

participants

Answer 3

34 sets of identical twins of whom 1 had gone to war

had pairs of twins that had
- one trauma exposed twin that developed/didn’t develop PTSD
- trauma-unexposed twin

Question 4

method

Answer 4

MRI scans to measure hippocampal volumes and then comparison of it across all twins

Question 5

results

Answer 5

found a negative correlation between hippocampal volume and symptom severity

veterans with PTSD had a lower hippocampal volume by avg of 10% than those veterans without

trauma-unexposed twins of the veterans that developed PTSD also had smaller hippocampi than the trauma-unexposed twins of veterans who didn’t

Question 6

conclusion

Answer 6

the evidence suggests that hippocampal volume is a pre-existing risk factor for the development of PTSD symptoms