title: Facilitation of naming in aphasia with auditory repetition: an investigation of neurocognitive mechanisms.
abstract: Prior phonological processing can enhance subsequent picture naming performance in individuals with aphasia, yet the neurocognitive mechanisms underlying this effect and its longevity are unknown. This study used functional magnetic resonance imaging to examine the short-term (within minutes) and long-term (within days) facilitation effects from a phonological task in both participants with aphasia and age-matched controls. Results for control participants suggested that long-term facilitation of subsequent picture naming may be driven by a strengthening of semantic-phonological connections, while semantic and object recognition mechanisms underlie more short-term effects. All participants with aphasia significantly improved in naming accuracy following both short- and long-term facilitation. A descriptive comparison of the neuroimaging results identified different patterns of activation for each individual with aphasia. The exclusive engagement of a left hemisphere phonological network underlying facilitation was not revealed. The findings suggest that improved naming in aphasia with phonological tasks may be supported by changes in right hemisphere activity in some individuals and reveal the potential contribution of the cerebellum to improved naming following phonological facilitation. Conclusions must be interpreted with caution, however, due to the comparison of corrected group control results to that of individual participants with aphasia, which were not corrected for multiple comparisons.
authors.affiliation: University of Queensland, Language Neuroscience Laboratory, Centre for Clinical Research, Royal Brisbane & Women's Hospital, Level 3, Building 71/918, Herston, Queensland 4029, Australia. shiree.heath@uq.edu.au
authors.forename: Shiree
authors.initials: S
authors.lastname: Heath
authors.forename: Katie L
authors.initials: KL
authors.lastname: McMahon
authors.forename: Lyndsey
authors.initials: L
authors.lastname: Nickels
authors.forename: Anthony
authors.initials: A
authors.lastname: Angwin
authors.forename: Anna D
authors.initials: AD
authors.lastname: MacDonald
authors.forename: Sophia
authors.initials: S
authors.lastname: van Hees
authors.forename: Eril
authors.initials: E
authors.lastname: McKinnon
authors.forename: Kori
authors.initials: K
authors.lastname: Johnson
authors.forename: David A
authors.initials: DA
authors.lastname: Copland
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D000368:Aged; D001037:Aphasia / Q000150:complications* / Q000473:pathology*; D001921:Brain / Q000098:blood supply; D001931:Brain Mapping; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000209:etiology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009275:Names; D010100:Oxygen / Q000097:blood; D011930:Reaction Time; D013997:Time Factors
chemical_list: D010100:Oxygen