Decoding of Basic Emotions from Dynamic Visual Displays in Dementia: A Sign of Loss of Positivity Bias in Emotional Processing in Cognitively Unhealthy Aging?

Difficulties in recognizing emotional signals might have serious implications for social interactions. Neurodegenerative diseases that affect neural networks involved in emotional displays processing might thus be connected with a disproportionate impairment in social life. This study aimed at examining the ability to decode basic emotions from dynamic visual displays in mild to moderate dementia. Thirty old adults diagnosed as demented, and 30 gender-matched healthy controls were administered a measure of emotion evaluation. The groups did not differ significantly in age and educational level. The emotion evaluation test was designed to examine a person’s ability to visually identify basic emotions and discriminate these from neutral expressions, when they were expressed as dynamic, subtle, day-to-day expressions. Results showed that demented participants had a great difficulty in recognizing the positively valenced emotions of happiness and pleasant surprise, while sadness, anger, and anxiety were the easiest emotions to recognize. Healthy controls were almost excellent on happiness recognition, while discrimination of non-emotional displays was the most difficult condition often mislabeled as anxiety or pleasant surprise. Results were mainly discussed in terms of socio-emotional selectivity theory positing that only older adults capable of exerting cognitive controlled favor emotional over non-emotional and positive over negative information