title: The effect of age on cognitive performance of frontal patients.
abstract: Age is known to affect prefrontal brain structure and executive functioning in healthy older adults, patients with neurodegenerative conditions and TBI. Yet, no studies appear to have systematically investigated the effect of age on cognitive performance in patients with focal lesions. We investigated the effect of age on the cognitive performance of a large sample of tumour and stroke patients with focal unilateral, frontal (n=68), or non-frontal lesions (n=45) and healthy controls (n=52). We retrospectively reviewed their cross sectional cognitive and imaging data. In our frontal patients, age significantly predicted the magnitude of their impairment on two executive tests (Raven's Advanced Progressive Matrices, RAPM and the Stroop test) but not on nominal (Graded Naming Test, GNT) or perceptual (Incomplete Letters) task. In our non-frontal patients, age did not predict the magnitude of their impairment on the RAPM and GNT. Furthermore, the exacerbated executive impairment observed in our frontal patients manifested itself from middle age. We found that only age consistently predicted the exacerbated executive impairment. Lesions to specific frontal areas, or an increase in global brain atrophy or white matter abnormalities were not associated with this impairment. Our results are in line with the notion that the frontal cortex plays a critical role in aging to counteract cognitive and neuronal decline. We suggest that the combined effect of aging and frontal lesions impairs the frontal cortical systems by causing its computational power to fall below the threshold needed to complete executive tasks successfully.
authors.affiliation: Department of Neuropsychology, National Hospital for Neurology and Neurosurgery, London, UK; Dipartimento di Psicologia, Università di Palermo, Italy. Electronic address: l.cipolotti@ucl.ac.uk.
authors.forename: Lisa
authors.initials: L
authors.lastname: Cipolotti
authors.affiliation: Department of Neuropsychology, National Hospital for Neurology and Neurosurgery, London, UK.
authors.forename: Colm
authors.initials: C
authors.lastname: Healy
authors.affiliation: Department of Neuropsychology, National Hospital for Neurology and Neurosurgery, London, UK.
authors.forename: Edgar
authors.initials: E
authors.lastname: Chan
authors.affiliation: Centre for Cognitive Ageing and Cognitive Epidemiology, Human Cognitive Neuroscience, Department of Psychology, University of Edinburgh, Edinburgh, UK.
authors.forename: Sarah E
authors.initials: SE
authors.lastname: MacPherson
authors.affiliation: Department of Neuroradiology, National Hospital for Neurology and Neurosurgery, London, UK.
authors.forename: Mark
authors.initials: M
authors.lastname: White
authors.affiliation: Institute of Cognitive Neuroscience, University College London, UK.
authors.forename: Katherine
authors.initials: K
authors.lastname: Woollett
authors.affiliation: Wolfson Neurorehabilitation Unit, Queen Mary's Hospital, London, UK.
authors.forename: Martha
authors.initials: M
authors.lastname: Turner
authors.affiliation: School of Psychology, The University of Queensland, Brisbane, Australia.
authors.forename: Gail
authors.initials: G
authors.lastname: Robinson
authors.affiliation: Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy.
authors.forename: Barbara
authors.initials: B
authors.lastname: Spanò
authors.affiliation: Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Bozzali
authors.affiliation: Institute of Cognitive Neuroscience, University College London, UK; International School for Advanced Studies (SISSA-ISAS), Trieste, Italy.
authors.forename: Tim
authors.initials: T
authors.lastname: Shallice
mesh_terms: D000328:Adult; D000367:Age Factors; D001921:Brain / Q000473:pathology; D001932:Brain Neoplasms / Q000473:pathology / Q000523:psychology*; D003071:Cognition / Q000502:physiology*; D056344:Executive Function / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D020521:Stroke / Q000473:pathology / Q000523:psychology*; D057190:Stroop Test
keywords: Aging; Cognitive performance; Executive functions; Frontal lesions non-frontal lesions