Table 2.
Summary of clinical studies assessing the OXT system manipulation effects on fear extinction.
| Subjects (Number) |
Study Design | Route of Administration | Drug Administered | Time of Administration | Effect on Fear Extinction | Reference |
|---|---|---|---|---|---|---|
| Healthy volunteers (44) |
Double-blind Placebo-controlled study |
IN | OXT (24 IU) | Pre-extinction | −At the beginning of extinction training No effect in the middle phase +in the late phase |
[184] |
| Healthy volunteer (62) |
Double-blind Placebo-controlled study |
IN | OXT (24 IU) | Post-conditioning and Pre-extinction | −At the beginning of extinction training +in the late phase |
[73] |
| Healthy volunteers (61) |
Double-blind Placebo-controlled study |
IN | OXT (40 IU) | Post-conditioning | + | [219] |
| Healthy volunteers (15) |
Double-blind Placebo-controlled study |
IN | OXT (27 IU) | Pre-conditioning | No effect | [65] |
| SAD Patients (25) |
Double-blind Placebo-controlled study |
IN | OXT (24 IU) | Pre-exposure therapy |
+(in combination with exposure therapy) |
[220] |
| Arachnophobic Patients (23) |
Double-blind Placebo-controlled study |
IN | OXT (24 IU) | Pre-exposure therapy |
- | [184] |
| PTSD Patients (37) vs. Healthy Subjects (40) |
Placebo-controlled Crossover study |
IN | OXT (40 IU) | Pre-exposure therapy |
+(in combination with exposure therapy) |
[68] |
| PTSD Patients (17) |
Double-blind Placebo-controlled study |
IN | OXT (40 IU) | Pre-exposure therapy |
− | [30] |
| PTSD Patients (range = 37–41) |
Double-blind Placebo-controlled study |
IN | OXT (40 IU- single dose) |
Pre-fMRI | − | [72] |
| PTSD Patients (107) |
Double-blind Placebo-controlled study |
IN | OXT (40 IU- multiple doses) |
Post-trauma | + | [72] |
+ Enhancement; − Impairment; IN, intranasal administration; OXT, synthetic oxytocin; fMRI, functional magnetic resonance imaging; IU, international units.