Dementia can affect a person's ability to recognise the meaning of common emotional words such as ‘thrilled’ and ‘annoyed’, according to new research.
Dr Sharpley Hsieh and colleagues from Neuroscience Research Australia explored how people with different types of dementia comprehend words describing feelings, such as ‘doubt’ and ‘hopeful’.
“People use emotion words in everyday conversation and don't realise it. How often do we use sentences such as ‘I'm frustrated’ or ‘she’s impressed’? These are key words and you have to know them to understand a sentence,” Dr Hsieh explains.
Dr Hsieh found people with Alzheimer's disease are still able to understand these kinds of words, but people with other types of dementia are not.
People suffering from semantic dementia (a type of front temporal dementia) which is the second most common dementia in people under 65 years experience a severe loss of word and conceptual knowledge. This latest study confirms for this group of people, their understanding of emotion words is also severely affected.
“You can easily show a picture of a car to test this word, or a smiling face to show happiness, but feelings such as frustration or embarrassment are difficult to depict and so until now we haven't been able to look at whether these concepts are lost in people with different dementias,” Dr Hsieh says.
These findings have implications for sufferers of dementia, carers and families.
“Losing the concept of a toaster, for example, will impact upon a person's quality of life, but the prevalence of words used to communicate feelings and emotion in our language must make the lack of understanding of these words so devastating for patients and their carers,” Dr Hsieh says.
This study, published in the journal Neuropsychology, compared healthy people without dementia to people with semantic dementia, behavioural-variant front temporal dementia and Alzheimer's disease.
Two tests were given. The first asked patients to couple feelings such as 'anger' with 'fury' or 'remorse'; the second asked patients to associate words such as 'terror' in the right context such as 'hiding' or 'playing'.
Patients with Alzheimer's disease demonstrated the most successful level of comprehension across tests; people with behavioural-variant front temporal dementia showed a mixed response depending on the test. Patients with semantic dementia were the most impaired on both tests.