Early-onset dementia is often mistaken for depression, putting patients at risk for not getting the proper treatment they need. A team of Australian researchers has discovered that a profound loss of ability to experience pleasure is related to the degeneration of “hedonic hotspots” in the brain. Because people report a lack of happiness in life, physicians can mistake it for depression.
These “hedonic hotspots” in the brain are where pleasure mechanisms are concentrated. The research team from the University of Sydney revealed marked degeneration or atrophy in the frontal and striatal areas of the brain. This has been related to diminished reward-seeking in patients with frontotemporal dementia (FTD).
The Study of FTD
This new study is the first of its kind to analyze the loss of pleasure in patients with FTD. The clinical definition for a loss of ability to experience pleasure is called anhedonia. This condition is also common in people with depression, bipolar disorder, and obsessive-compulsive disorder and can be highly disabling for the individual.
The study included patients with FTD, which generally affects people aged 40 – 65. They recorded a dramatic decline from pre-disease onset compared to patients with Alzheimer’s disease who were not found to have significant anhedonia. These findings point to the importance of considering anhedonia as a primary symptom of FTD. In these patients, neural drivers were found in areas that are distinct from apathy or depression.
The paper’s senior author Professor Muireann Irish said, “Our findings also reflect the workings of a complex network of regions in the brain, signaling potential treatments.”
“Future studies will be essential to address the impact of anhedonia on everyday activities, and to inform the development of targeted interventions to improve quality of life in patients and their families.”
Much of the human experience is motivated by the experience of pleasure, but most people take this for granted. For those who suffer from anhedonia, the world is a much different experience.
As the condition is linked to other neurodegenerative disorders, it helps to bring light on how it can help diagnose early-onset dementia and create potential treatments. By ensuring high quality of life in patients with early-onset dementia and administering proper treatments, the pace at which the condition progresses has been previously found to be reduced.