Impaired facial emotion recognition and preserved reactivity to facial expressions in people with severe dementia.

The ability of decoding the emotional facial expressions may be early damaged in frontotemporal dementia, but relatively well preserved in the Alzheimer's disease (AD). Nevertheless, the data about the relationship of the dementia severity with the ability of recognizing the face emotions are conflicting and insufficient, mainly for the moderate-severe stage of the disease. The present study extends to the existing literature by: (1) assessing people in the moderate and severe stage of dementia, compared with people without cognitive impairment; (2) assessing not only recognition but also reactivity to the facial expression of emotion. The capability of understanding the facial emotions has been evaluated in 79 patients with dementia compared to 64 healthy elderly people. The test consisted in showing them 14 photographic representations of 7 emotions both from male and from female faces, representing happiness, sadness, fear, disgust, boredom, anger and surprise. Patients were asked to observe the face and to recognize the emotion either with a denomination or a description. Then the spontaneous reactivity to the face expressions was videotaped and classified as a congruous or incongruous reaction by two independent observers who showed a good inter-rater reliability. Of the patients, 53% with dementia recognized up to 5 emotions out of 14, while in the healthy controls this number of mean recognition raised to 8.4, a value reached by the patients who scored 16 at MMSE. The most identified emotion is happiness both for the patients and for the controls. In general, positive emotions are better recognized than the negative ones, confirming the literary data. About the reactions to face emotion stimuli, there is no significant difference for any of the face emotion between the control group and the people with dementia. These data show that patients with dementia can recognize and react to facial emotions also in the severe stage of the disease, suggesting the usefulness of a non-verbal, emotional communication and supporting the need for more emotional education for care givers, both relatives and professionals.