Disrupted imagery, disrupted scenes: mental scene construction in behavioural-variant frontotemporal dementia

Mental scene construction-the ability to generate coherent, spatially organized, and vivid internal representations-is central to episodic memory, future thinking, and social cognition. However, in behavioral-variant frontotemporal dementia (bvFTD), relatively little is known about how core components of mental scene construction, such as visual imagery, spatial imagery, imagery vividness, and visuospatial working memory, are affected. In this study, 21 bvFTD patients and 25 matched controls completed tasks assessing these processes: the Taller/Wider Task, the Clock Angles Task, the Vividness of Visual Imagery Questionnaire, and forward and backward Corsi Block-Tapping. Patients with bvFTD showed marked impairments across all tasks. In this group, general cognitive functioning was positively correlated with performance on the visual imagery, spatial imagery, and visuospatial working memory tasks, but not with imagery vividness. These findings highlight marked impairments in fundamental imagery and mental scene construction, consistent with broader disruptions in visuospatial processing and working memory processes in bvFTD.