Studies in depressed patients have demonstrated the presence of emotional bias toward negative stimuli, as well as dysregulated brain serotonin function. Feder et al (2011, Biological Psychiatry) compared the effects of ATD on both an emotional processing (affective go/no-go) and a planning task (Tower of London) in never-depressed healthy volunteers at high and low familial risk for depression. There was a significant treatment by valence by group interaction on the affective go/no-go, driven primarily by a greater frequency of inappropriate responses to sad than to happy distracters in the high-risk group during ATD. No group differences were observed on the Tower of London. This allows for the conclusion that asymptomatic individuals at high familial risk for depression show abnormalities in emotional processing when serotonin synthesis is decreased under ATD, supporting emotional processing disturbances as potential trait-level abnormalities associated with the risk of mood disorder. Few studies investigate serotonergic function in the elderly using ATD. Mace et al (2011, Journal of Psychopharmacology) compared the effects of ATD on mood, cognitive function and motor function in two groups of healthy volunteers, aged 50-69 and 70-89 years respectively. ATD showed no significantly different effects between age groups, suggesting relatively little functional change across these age ranges. However, when comparing the results to studies in much younger age groups there was more evidence of an adverse effect of ATD on psychomotor function and working memory. Despite inclusion of subjects with a family history of depression ATD showed no effects on mood.