title: Degradation of cognitive timing mechanisms in behavioural variant frontotemporal dementia.
abstract: The current study examined motor timing in frontotemporal dementia (FTD), which manifests as progressive deterioration in social, behavioural and cognitive functions. Twenty-patients fulfilling consensus clinical criteria for behavioural variant FTD (bvFTD), 11 patients fulfilling consensus clinical criteria for semantic-variant primary progressive aphasia (svPPA), four patients fulfilling criteria for nonfluent/agrammatic primary progressive aphasia (naPPA), eight patients fulfilling criteria for Alzheimer׳s disease (AD), and 31 controls were assessed on both an externally- and self-paced finger-tapping task requiring maintenance of a regular, 1500 ms beat over 50 taps. Grey and white matter correlates of deficits in motor timing were examined using voxel-based morphometry (VBM) and diffusion tensor imaging (DTI). bvFTD patients exhibited significant deficits in aspects of both externally- and self-paced tapping. Increased mean inter-response interval (faster than target tap time) in the self-paced task was associated with reduced grey matter volume in the cerebellum bilaterally, right middle temporal gyrus, and with increased axial diffusivity in the right superior longitudinal fasciculus, regions and tracts which have been suggested to be involved in a subcortical-cortical network of structures underlying timing abilities. This suggests that such structures can be affected in bvFTD, and that impaired motor timing may underlie some characteristics of the bvFTD phenotype.
authors.affiliation: Dementia Research Centre, Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London WC1N 3BG, United Kingdom; National Hospital for Neurology and Neurosurgery, UCLH NHS Foundation Trust, Queens Square, London WC1N 3BG, United Kingdom. Electronic address: susie.henley@ucl.ac.uk.
authors.forename: Susie M D
authors.initials: SM
authors.lastname: Henley
authors.affiliation: Dementia Research Centre, Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London WC1N 3BG, United Kingdom. Electronic address: l_downey1@hotmail.com.
authors.forename: Laura E
authors.initials: LE
authors.lastname: Downey
authors.affiliation: Department of Medical Statistics, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, United Kingdom. Electronic address: jennifer.nicholas@lshtm.ac.uk.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Nicholas
authors.affiliation: Dementia Research Centre, Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London WC1N 3BG, United Kingdom. Electronic address: k.kinnunen@ucl.ac.uk.
authors.forename: Kirsi M
authors.initials: KM
authors.lastname: Kinnunen
authors.affiliation: Dementia Research Centre, Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London WC1N 3BG, United Kingdom. Electronic address: hannah.golden.11@ucl.ac.uk.
authors.forename: Hannah L
authors.initials: HL
authors.lastname: Golden
authors.affiliation: Dementia Research Centre, Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London WC1N 3BG, United Kingdom. Electronic address: aisling.buckley@imperial.nhs.uk.
authors.forename: Aisling
authors.initials: A
authors.lastname: Buckley
authors.affiliation: Dementia Research Centre, Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London WC1N 3BG, United Kingdom. Electronic address: colin.mahoney@ucl.ac.uk.
authors.forename: Colin J
authors.initials: CJ
authors.lastname: Mahoney
authors.affiliation: Dementia Research Centre, Department of Neurodegenerative Disease, UCL Institute of Neurology, University College London, London WC1N 3BG, United Kingdom. Electronic address: s.crutch@ucl.ac.uk.
authors.forename: Sebastian J
authors.initials: SJ
authors.lastname: Crutch
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000503:physiopathology; D018888:Aphasia, Primary Progressive / Q000503:physiopathology; D002525:Cerebellar Cortex / Q000473:pathology*; D005260:Female; D057180:Frontotemporal Dementia / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D013998:Time Perception / Q000502:physiology*
keywords: Cerebellum; Finger tapping; Frontotemporal dementia; Motor timing