Explicit identification and implicit recognition of facial emotions: I. Age effects in males and females across 10 decades.

A number of psychiatric and neurological disorders are characterized by impairments in facial emotion recognition. Recognition of individual emotions has implicated limbic, basal ganglionic, and frontal brain regions. Since these regions are also implicated in age-related decline and sex differences in emotion processing, an understanding of normative variation is important for assessing deficits in clinical groups. An internet-based test ("WebNeuro") was administered to 1,000 healthy participants (6 to 91 years, 53% female) to assess explicit identification of basic expressions of emotion (happiness, sadness, fear, anger, disgust, neutral). A subsequent implicit recognition condition was based on a priming protocol, in which explicit identification provided the "study" phase. Responses were most accurate for happiness and slowest for fear in the explicit condition, but least accurate for happiness and fastest for fear in the implicit condition. The effects of age, by contrast, showed a similar pattern for both explicit and implicit conditions, following a nonlinear distribution in which performance improved from childhood through adolescence and early adulthood and declined in later adulthood. Females were better than males at explicit identification of fear in particular. These findings are consistent with the priority of threat-related signals, but indicate opposing biases depending on whether emotion processing is conscious or nonconscious. The lifespan trends in emotion processing over 10 decades point to an interaction of brain-based (maturation, stability, and then atrophy of cortical and subcortical systems) and experiential contributing factors. These findings provide a robust normative platform for assessing clinical groups.