In particular, previous studies found that whole brain binding of the positron emission tomography (PET) radioligand [<sup>11</sup>C](R)-rolipram to PDE4 was decreased in individuals with major depressive disorder; eight weeks of antidepressant treatment rescued this decrease in [<sup>11</sup>C](R)-rolipram binding. The gene discussed is PDE4A; the disease is major depressive disorder.