Disruption of temporal processing in a subject with probable frontotemporal dementia.
Previous research suggests that the frontal lobes are essential for temporal processing. We report a patient, MN, with probable frontotemporal dementia (FTD) who was tested on a battery of timing tasks with stimuli in the sub- and supra-second range. MN demonstrated a substantial over-estimation and under-production of target intervals on estimation and production tasks respectively but was as accurate as controls on a reproduction task. Furthermore, this deficit was markedly different for auditory and visual stimuli on production and estimation tasks; estimates of the duration of auditory stimuli were three to four times longer than for comparable visual stimuli. She performed normally on a task requiring her to judge whether a stimulus was longer or shorter than a standard duration with both sub- and supra-second stimuli. She performed well on control tasks involving estimation, production and reproduction of line lengths suggesting that her deficits were not attributable to a generalized cognitive impairment or an inability to make magnitude judgments. These data suggest that bifrontal pathology disrupts the "clock" or memory for time.
Wiener
Martin
M
Department of Neurology, University of Pennsylvania School of Medicine, 3400 Spruce Street, Philadelphia, PA 19104, USA.
Coslett
H Branch
HB
D001288:Attention / Q000502:physiology; D001307:Auditory Perception / Q000502:physiology*; D001683:Biological Clocks / Q000502:physiology; D003072:Cognition Disorders / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000503:physiopathology; D035061:Control Groups; D003704:Dementia / Q000175:diagnosis / Q000503:physiopathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D005625:Frontal Lobe / Q000000981:diagnostic imaging / Q000503:physiopathology*; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007600:Judgment / Q000502:physiology; D008568:Memory / Q000502:physiology; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D049268:Positron-Emission Tomography; D017397:Prefrontal Cortex / Q000000981:diagnostic imaging / Q000503:physiopathology; D011930:Reaction Time / Q000502:physiology; D013702:Temporal Lobe / Q000503:physiopathology; D013998:Time Perception / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*
D019788:Fluorodeoxyglucose F18