Scenario I The Following Scenario Presents Fabricated Data Consistent with the Results

Scenario I
The following scenario presents fabricated data consistent with the results of the following study:
Gilbertson, M. W., Shenton, M. E., Ciszewski, A., Kasai, K., Lasko, N .B., Orr, S. P., & Pitman, R. K. (2002) . Smaller hippocampal volume predicts pathologic vulnerability to psychological trauma. Nature Neuroscience, 5, 1242-1247.
Persons who live through a traumatic experience may develop posttraumatic stress disorder (PTSD) . PTSD is characterized by chronic physiological arousal, recurrent unwanted thoughts or images, and avoidance of things that bring the trauma to mind, with symptoms persisting for more than one month. Persons with PTSD also are at risk for other psychological disorders, with substance abuse disorder being a common comorbid diagnosis. In the last two decades, a number of studies have demonstrated that persons with PTSD have smaller hippocampi than controls. This may result from the neurotoxic effects of stress hormones examined the hippocampal volume of combat veterans with and without PTSD who each had an identical twin who never served in the military. Fabricated results consistent with this study are shown in Figure 15.1.
Figure 15.1
-(Scenario I) The purpose of studying monozygotic twins of combat veterans in the Gilbertson et al. (2002) study was to:

A) demonstrate that combat exposure causes PTSD.
B) demonstrate that combat exposure is associated with PTSD.
C) determine if smaller hippocampi are the causes or consequences of PTSD.
D) control for all other third variables related to genetics other than hippocampal volume.