Sustained attention in dementia with Lewy bodies: a task-based fMRI study

Introduction: Patients with Dementia with Lewy Bodies (DLB) typically experience attentional deficits. Understanding these deficits and the underlying neural correlates is crucial as sustained attention supports higher level cognitive functions. The objective of this study was to investigate the patterns of brain connectivity during a functional magnetic resonance imaging (fMRI) sustained attention task in a DLB group compared with healthy controls (HC). Methods: In this study, 30 DLB patients and 25 HC underwent a comprehensive neuropsychological assessment and a brain 3T MRI protocol that included a high-resolution structural sequence (T1-w 3D MPRAGE) and a task-based fMRI study using an auditory Psychomotor Vigilance Task (PVT). Results: DLB patients performed worse in neuropsychological tests mainly related to the visuospatial domain and had poorer performance than HC on sustained attention (i.e., PVT) in terms of lapses and longer response times. Moreover, during the PVT, the DLB group exhibited significantly lower activation in the precuneus, intracalcarine cortex, angular gyrus and cuneus, regions implicated in sustained attention. Discussion: Overall, the identification of a distinct pattern of brain activity related to attention impairment in DLB patients offers opportunities for the development of tailored cognitive stimulation treatments.