MRI Reveals Deterioration of Brain's Reward Circuitry in Younger-Onset Dementia

A study in Brain analyzed magnetic resonance imaging (MRI) data to differentiate anhedonia, a signature symptom in patients with frontotemporal dementia (FTD), reports Physicsworld . The investigators aimed to define FTD through cognitive and neuroimaging assessments. Behavioral testing uncovered a high incidence of anhedonia in FTD syndromes compared with other types of dementia, with such patients suffering a lack of interest in rewarding experiences and enjoyable hobbies. Voxel-based morphometry analysis of participants' whole-brain MRIs were conducted to characterize voxel-by-voxel changes in gray matter signal intensities, which revealed that the neural circuitry of anhedonia diverges from that of apathy and depression. FTD patients diagnosed with anhedonia exhibit deterioration mostly in a frontostriatal gray matter network that governs the experience of pleasure. "Our findings are . . . important for understanding the subjective experience of the person living with dementia, for the delivery of personalized care, as well as revealing broader insights into a fundamental aspect of the human condition," said Muireann Irish at the University of Sydney.