PET comparisons between placebo and fluoxetine recipients showed metabolic increases in the prefrontal cortex, premotor cortex, anterior cingulate, parietal insula, posterior insula and posterior cingulate, as well as decreases in the subgenual cingulate, parahippocampus and thalamus in both groups. The fluoxetine group also showed increases in the brainstem and decreases in the striatum, hippocampus and anterior insula, and overall showed a greater magnitude of changes compared to the placebo group (Mayberg et al, 2002) . This study indicated that although the effects of the placebo may seem the same, additional changes in the brain due to the antidepressant appear to have a longer lasting effect and be more effective in the long term..