Dementia affects ability to recognise negative emotions

A new study has shown that people with frontotemporal dementia, one of the most common forms of the condition, are more likely to lose the ability to recognise negative emotions, such as anger, fear and disgust, than positive emotions such as happiness.Along with various other symptoms affecting behaviour and language, all people with frontotemporal dementia experience difficulty in recognising emotions. Up until now, however, it was not known whether the three subtypes of FTD have the same emotion-recognition deficits, and whether certain techniques could help overcome these deficits.Dr Piguets team tested the ability of 41 people with FTD to recognise six basic facial emotions (anger, disgust, fear, happiness, sadness and surprise).The team also performed a second test, using faces with exaggerated emotions, to determine whether more intensely expressed emotions would help with recognition. Of the three FTD subtypes, the researchers found that those people with the semantic dementia subtype were the most impaired when it came to recognising emotions.Patients with the progressive non-fluent aphasia and behavioural-variant FTD subtypes also had emotion-recognition deficits, particularly for angry and sad faces, but tended to improve if the emotions were made more obvious.