Study Shows Why Some Dementia Patients Lack Empathy

Patients with Alzheimer’s disease generally remain warm and engaged despite their cognitive decline, but those with the behavioural-variant of frontotemporal dementia (bvFTD) undergo a jarring change in personality.

These early-onset dementia patients have blunted emotions and become puzzled by affection, uninterested in socialising and less responsive to the feelings of others.

But a study published in the Journal of Alzheimer’s Disease may give comfort to carers who have borne the brunt of these changes. It indicates that the changes result from fading grey matter in the region of the brain that governs empathy.

Researchers from Neuroscience Research Australia investigated 71 individuals including 25 with Alzheimer’s, 24 with bvFTD and 22 healthy older control participants through cognitive assessments, carer interviews and neuroimaging.

Both the experimental groups had reduced capacity to understand and appreciate the emotions of others, known as cognitive empathy. But the bvFTD patients were significantly more impaired when it came to sharing the emotions and emotional experiences of others – or affective empathy.

The impairment in cognitive empathy among the Alzheimer’s group was found to be a consequence of their overall cognitive decline, rather than an impairment in empathy per se.

So while they found it difficult to explain how a book character might be feeling, they were still likely to become upset if they saw somebody crying in the street.

But among the bvFTD patients, the loss of empathy was related to patchy grey matter in the frontoinsular cortices of the brain, the integrity of which is critical to social functioning.

Lead author Muireann Irish said this explained why Alzheimer’s patients continued to be socially appropriate in spite of the decline in cognitive function. “There isn’t the change in personality, which I think is one of the most jarring things about frontotemporal dementia patients,” Dr Irish said. “(This study) gives more knowledge and insight to the caregivers that there’s an organic reason for this change that becomes so distressing.” “Empathy is an abstract concept in a way. It's not as easily quantified as memory loss or changes in language and it can be seen as a personality issue or somebody being deliberately unsympathetic, but this shows there’s a region in the brain that changes.”