What does it say about a person if they cannot tell if someone is being sarcastic or lying?
Katherine Rankin, Ph.D., a member of the UCSF’s Memory and Aging Center and senior author of a recent study, suggests that it may be possible to spot people with particular neurodegenerative diseases early by looking for the telltale sign of their inability to detect lies.
UCSF’s website states that the ability to detect lies resides in the brain’s frontal lobe. In diseases like frontotemporal dementia, an area that progressively degenerates because of the accumulation of damaged proteins, the frontal lobe plays an important part in complex, higher-order human behaviors.
Would the inability to detect sarcasm and lies actually match the brain regions hit early in these diseases?
The UCSF researchers focused on the fact that people with frontotemporal dementia often lose the ability to detect sarcasm and lies compared to a person who has Alzheimer’s . The article goes on to purport that doctors have observed evidence of this for years. People suffering from this disease sometimes lose significant amounts of money to online scams and telemarketers because of their blind trust.
175 seniors participated in this study and more than half had a neurodegenerative disease. They were shown a video of two people conversing. In the video one of the conversers would occasionally lie or use sarcasm, which was prevalent both in verbal and nonverbal cues. The participants were then asked yes or no questions about the video. Patients with frontal dementia were unable to discern between sincere and insincere speech. An interesting fact is that patients with Alzheimer’s disease fared much better.
News Medical also commented on this new research. They state that frontotemporal dementia makes up about 5% of patients with dementia and tends to occur at a younger age (40-70) then say Alzheimer’s disease, which accounts for nearly 80% of such patients.
“If somebody has strange behavior and they stop understanding things like sarcasm and lies, they should see a specialist who can make sure this is not the start of one of these diseases,” said Rankin.