Figures & data
Figure 1. Overview of within-subjects crossover study design. Participants were randomly assigned to the oxytocin or placebo condition prior to the first scanning day (Visit 2), then were assigned to the opposite condition for the second scanning day (Visit 3).
Figure 2. Illustration of the facial affect recognition task. (a) Six task blocks depicting male or female faces expressing angry, happy or fear emotions were interleaved with rest blocks consisting of a central crosshair for visual fixation. Each task block lasted 27.8 s followed by a 5-s gender identification block. Each rest block lasted 27.5 sec. (b) Illustration of a single trial within each task block. An emotional face was presented for 50 ms followed by a neutral face mask for 167 or 183 ms followed by a completely blank screen for 291 ms. Fifty-six trials were presented in a single task block. (c) Illustration of the gender identification block, which lasted 5 s. Subjects were asked ‘What gender were the faces that you just saw? MALE – Press Thumb, FEMALE – Press Index Finger’.
Table 1. Demographic and clinical characteristics by group.
Figure 3. Mean bilateral amygdala response in participants with PTSD and childhood trauma-exposed control participants as a function of treatment with placebo or intra-nasal oxytocin. Error bars are standard of the mean.
Figure 4. Scatterplots illustrating the correlation between change in (a) left amygdala and (b) right amygdala fMRI response due to drug (Oxytocin minus Placebo) as a function of Childhood Trauma Questionnaire scores. Positive Oxytocin minus Placebo difference scores reflect greater amygdala activation on oxytocin and negative Oxytocin minus Placebo difference scores reflect greater amygdala activation on placebo. OT = Oxytocin. PBO = Placebo. PTSD = Posttraumatic stress disorder group. SD = Standard deviation.
Table 2. Clusters and local maxima for activation in the Fear > Rest contrast for each group and drug condition.
Figure 5. Results of the voxel-wise general linear model analysis for the Fear > Rest contrast for each participant group (PTSD and childhood trauma-exposed groups) and drug condition (yellow = placebo, blue = oxytocin). Activation is significant at a cluster-corrected threshold of Z > 2.33, p = .05. Crosshairs in each brain slice are centred on left amygdala, right amygdala or right paracingulate region. MNI x-coordinate is shown for each slice.
