In studies investigating age differences in the ability to recognize
positive facial expressions (i.e., smiles), researchers have
asked participants to decide which of six basic emotions (anger,
fear, sadness, disgust, surprise, or happiness) a smiling individual
is portraying. In studies with this task, at least one of the age
groups shows ceiling effects (Issacowitz et al., 2007), thereby
limiting the potential to detect age-related differences in happiness
perception. It is thus important to use measures that provide more
sensitive indices of the recognition of positive emotion to investigate
age differences in the perception of happiness. We address
this issue in the present research by using stimuli that portray
subtle but socially meaningful differences in smile physiognomy.